Boom Baby!!!

[TomsSVX]

Well this is the remains of the big boom...Cyl #5 like many of us expected

http://www.subaru-svx.net/photos/files/TomsSVX/41105.JPG

http://www.subaru-svx.net/photos/files/TomsSVX/41106.JPG

http://www.subaru-svx.net/photos/files/TomsSVX/41107.JPG

http://www.subaru-svx.net/photos/files/TomsSVX/41106.JPG

Nice huh?? I didn't pull the even number pistons yet but I did pull one through 5

Tom

[SVXRide]

Ouch! How did the cylinder wall look? Weird that only one cylinder went that severely. Makes me start to wonder if there isn't an issue with the fuel distribution on the EG33...
-Bill

[TomsSVX]

the shortest distance to travel for air is the rear cylinders i believe... I understood it before but not so much now:o Anyway... The block went completely unscathed to the naked eye:D :D So this means this block will be sleeved and built

Tom

[NikFu S.]

Slight blur + I'm not a piston guy = what am I looking at exactly?

Little pieces of the piston broke of or disintegrated?

Is that a piston ring?

[longassname]

doesn't look like it was hot...looks like ring failure maybe?

[Trevor]

Do I see a broken middle land? :confused: Did anything pick up/sieze even slightly in the bore? :confused:

You are being sort of nasty presenting puzzles, while not showing all the evidence. ;) Quiz SVX :confused:

[TomsSVX]

The piston failed between the two compression rings... Didn't touch the oil ringat all. The top ring was in 1 piece but bent up awfule nice... The lower ring was completely destroyed along with the middle ground... It also cracked the piston from the point of destruction all the way down to right around the piston pin... Luckily the piston never let go and all the broken pieces stayed withing their original locations. The cylinder walls were left alone like I said with no scratches and the hatch is still fully visible on a motor with 140k... Not too shabby for as much detonation as that motor saw

Tom

[TomsSVX]

Here is the pic of the piece of the middle ground that fell out after extraction.

http://www.subaru-svx.net/photos/files/TomsSVX/41112.JPG

Tom

[Trevor]

Here is the pic of the piece of the middle ground that fell out after extraction.

Tom

Hooooray, I won the quiz, as I was correct regarding a broken land/middle ground. :D

[solarsvx]

im not surprised, :rolleyes:

[TomsSVX]

im not surprised, :rolleyes:

Well when you push beyond the limitations of your engine... things like this will happen. I have since then taken the boost back down to 9psi until I have this spare engine built when I will go back to 12psi and then go from there with it...

Tom

[TomsSVX]

After looking closer at the odd pistons I realized #3 had cracked as well and once I removed the rings... all the pieces fell right out. Then I pulled the even pistons where I found #2 and #4 had also gone the route of the dodo... Killed 4 pistons and the motor still ran:rolleyes: Only the #5 was the one that showed it in plain view... the others I hade to remove the rings to get the pieces out... All middle ground breaks... all on the top/bottom of the piston(if the motor is sitting as it does in the car). After looking at the bottom side of the piston I can see why. It seems there is very little material there to hold it all together and these are by far the weakest points in the piston.

Tom

[SVXRide]

After looking closer at the odd pistons I realized #3 had cracked as well and once I removed the rings... all the pieces fell right out. Then I pulled the even pistons where I found #2 and #4 had also gone the route of the dodo... Killed 4 pistons and the motor still ran:rolleyes: Only the #5 was the one that showed it in plain view... the others I hade to remove the rings to get the pieces out... All middle ground breaks... all on the top/bottom of the piston(if the motor is sitting as it does in the car). After looking at the bottom side of the piston I can see why. It seems there is very little material there to hold it all together and these are by far the weakest points in the piston.

Tom


Ah, destructive testing at its very best:eek: :p
-Bill

[Trevor]

Ah, destructive testing at its very best:eek: :p
-Bill

Exactly, but something must be learned from the losses involved. :( :)

In this instance a small cross section of material with very little mass has broken away. This could indicate multi stresses of short duration and therefore possibly detonation. Are there any other signs of such? :confused:

[TomsSVX]

I had a bunch of audible knock with this motor... WE were trying new software to try and get rid of it when I blew it up

Tom

[Trevor]

I had a bunch of audible knock with this motor... WE were trying new software to try and get rid of it when I blew it up

Tom

Well then, you and WE, have gleaned some useful information. Even if something along the same lines had been expected. :( :p

Is WE contributing $ :confused: LOL

[TomsSVX]

i didn't mean to capitalize the letters, dunno why I did:confused: , anywho the score has been settled and when it comes down to it... I blew my motor thats all. I replaced it and then F'd it up again... so I fixed it and now its running again:D :D My focus will now go to rebuilding SVX autos and rebuilding my engine to handle more boost with the cams and pistons LAN is cooking up. I will also go to eagle rods (Sti rods) and clevite bearings. Not sure if I should bother to sleave the motor as it seems relatively stout and it would def add a lot to the cost

Tom

[Trevor]

Tom,

LOL, looked like you had mates conspiring on a destructive test program.:confused: Sorry you were all on your own to sweep up the pieces. :eek:

[TomsSVX]

When I build a car... I do it all on my own. When I put all the pieces together... I will be the only one expected to pick those pieces up when the shatter...LAN did help me out with the newest software and even hardware for alt. and everything and I hold nothing against him and I will keep working with him on new developements

Tom

[SVXRide]

STi rods and clevite bearings...what a great idea!;)
-Bill (still trying to find out about main bearings...)

[TomsSVX]

No offense Bill, but i don't think I am gonna waste my time or money on Sti rods... Going straight to Eagle rods;) Hopefully the sale of my new pearly with a 5mt in it already will clear me for my build;)

Tom

[longassname]

Good choice. Same here. I ocassionally think about doing the cad for inserts to close deck the block but I haven't really delved into it yet. Think I should?

[TomsSVX]

I have heard closing the deck can cause coolant issues more so than sleeving it. I would like to find a good suby machine shop that has a lot of experience doing EJ motors if I were to get it done

Tom

[longassname]

I'm not sure about that. Close decking you are just welding a piece of heavy sheet metal at the outer edges of the block with holes to match the holes in the heads so the wajer jackets are unaffected.

I'm not convinced I want to do it. I just consider it every once in a while.


I have heard closing the deck can cause coolant issues more so than sleeving it. I would like to find a good suby machine shop that has a lot of experience doing EJ motors if I were to get it done

Tom

[TomsSVX]

I know that is what consists of closing the deck. I have just heard things...

Tom

[SVXRide]

No offense Bill, but i don't think I am gonna waste my time or money on Sti rods... Going straight to Eagle rods;) Hopefully the sale of my new pearly with a 5mt in it already will clear me for my build;)

Tom


Tom,
Understood. Can you post a pic of the Eagle rods? I'm curious as to how they differ from the STi rods. Are they dowelled? Weight?
-Bill

[longassname]

Eagle ESP H beam connecting rods:

4340 steel with 3/8 arp rod bolts and alignment sleeves. 530 plus or minus 1 gram per complete rod assembly.



Tom,
Understood. Can you post a pic of the Eagle rods? I'm curious as to how they differ from the STi rods. Are they dowelled? Weight?
-Bill

[TomsSVX]

Mike, I am having a hard time finding a source for Eagle Sti rods... they only have ej20t rods...

Tom

[longassname]

I believe the 1.8, 2.0, 2.2 rods are the right rods


Mike, I am having a hard time finding a source for Eagle Sti rods... they only have ej20t rods...

Tom

[oab_au]

Tom are going to pull the rods? It would be worth seeing what the upper half of the big end shell looks like. It will show how heavy the detonation was, before the rings and lands gave away.

It would be good to see how much detonation the pistons can stand.:)

Harvey.;)

[SVXRide]

http://www.subaru-svx.net/photos/files/SVXRide/39299.jpg

24.5 grams lighter than stock EG33 rods...how much lighter are the Eagle rods?

-Bill

[longassname]

well...i posted the weight of the eagle rod assemblies...how much do your rods weigh?

[SVXRide]

well...i posted the weight of the eagle rod assemblies...how much do your rods weigh?


Good question....Calling NeedForSpeed....Calling NeedForSpeed;) :D

-Bill (who doesn't have a precision gm scale around the house...)

[TomsSVX]

Ok good news... I just got the confirmation that the Eagle 2.2l rods LAN had recomended have the same dimensions as Sti rods and most of the performance SUby engines like the 2.0, 2.2 and 2.5... This means I will go ahead and order the Eagles with LAN so we can split one set:D

Harvey, I did remove the rods... they are fine and the bearings nor journals show any abnormal wear. These motors were built for more than what they have ever seen before

Tom

[cdigerlando]

I have also tossed this question around. It seems that deck closing would help not only to better seal the head gasket, but also to prevent the top of the sleave from moving around. I think o-ringing might also acheive this though, but would not have the added benifit of better sealing the gasket. Disadvantages I have heard include pinching down of the piston sleave top when the engine is warm. This is common when the decking is mearly "hammered" into place. Too much internal stress on the sleaves.

I have been corresponding with Howard of AR Fabrication. He has sleeving experience with all of the 4 cylinder subaru engines. Unfortunately he has none with the 6 cylinder engines. He is willing to do a build, but would want to source his own pistons. I was hoping to source LAN's pistons and head and valve train work, and just have Howard do the bottom end. But he does not want to do that. He would want to source everything in the bottom end. Now I am asking if he would do the heads too.

I'm a bit frustrated. I imagine I could pull the heads myself, send them to LAN, send the bottom end to Paeco (I have not heard too much good about them), and have them sleave and/or deck the bottom end. Then install the pistons myself and assemble the top end.

Tom:

Thanks for sacrificing your engine for the cause. I guess the pistons are not as strong as everyone thought. Thankfully you did not damage any other components in your motor. I'll let you know what I see when mine comes appart too. I did not have audible knock, but have extensive blowby. I'll let you know why. I think you are smart to change out the rods and bearings too. A thrown rod can really screw up a motor. Too much of a big gamble IMHO to do all of that work and have a rod fail.

Lets keep in touch. We are both looking at doing a build. Perhaps we can pool our efforts, and make it a bit more cost effective to have a shop work on two unusual motor builds instead of just one. Let me know if you are interested and I will let AR Fab know. Perhaps we can talk them into just sleaving and decking. Then do the rest of the assembly work ourselves or with a local machine shop.

[TomsSVX]

I do not think we need to worry about closing the deck or sleeving... I mean, we have no cracked or even heard of a cylinder wall cracking... We are not making insane power, just moderately good power in the overall realm of racing... The EG series motor is more stout that we give credit to. I think with better rods and bearings along with LAN's custom pistons, we will be fine for the lower end. Head gaskets are going to be an issue once we really start pushing the envelope but as it stands we can benfit more from a copper HG. It will be much more cost effective than closing the deck. The head will just need to be sent out to a head shp for a basic cleanup and assembly which should be able to be done at almost any shop... You can choose to do some porting and polishing but that is neither here nor there. It is not as complicated as it seems and you will discover this once you take down your old motor... I would not be surprised if your pistons let go in the same fashion as mine had. It is a weak point in the piston and you cannot expect great strength out of vaccum cast pistons in a fully forged motor.

Tom

[cdigerlando]

I do not think we need to worry about closing the deck or sleeving... I mean, we have no cracked or even heard of a cylinder wall cracking... We are not making insane power, just moderately good power in the overall realm of racing... The EG series motor is more stout that we give credit to. I think with better rods and bearings along with LAN's custom pistons, we will be fine for the lower end. Head gaskets are going to be an issue once we really start pushing the envelope but as it stands we can benfit more from a copper HG. It will be much more cost effective than closing the deck. The head will just need to be sent out to a head shp for a basic cleanup and assembly which should be able to be done at almost any shop... You can choose to do some porting and polishing but that is neither here nor there. It is not as complicated as it seems and you will discover this once you take down your old motor... I would not be surprised if your pistons let go in the same fashion as mine had. It is a weak point in the piston and you cannot expect great strength out of vaccum cast pistons in a fully forged motor.

Tom

Tom:

The big problem with doing any work on this engine is it is what we "think" it can hold and not what we "know" it will hold. I for one would prefer to pull the engine once and be done with it. Then again, I don't want to give a builder an open checkbook and say "have at it" though.....so it may be a mute point. Do you want to go in on head gaskets? Let me know. It should be cheaper to do them in bulk.

[TomsSVX]

i will be able to once I can sell my pearl car... I bought this car to fix up and resell so I can afford my engine build

Tom

[cdigerlando]

Let me know when you are ready. I'm kind of dead in the water until I can get this done. Good thing the WRX is running well.

[cdigerlando]

Also let me know if you want to sell me a maintenance manual CD, as a donation to the cause.

[oab_au]

Tom do we know what was the cause of the detonation? What was the spark advance at full throttle, that the engine was running then?

Harvey.;)

[TomsSVX]

I was running 10 degrees or retard at times... Sometime detonation would happen if I kept on it even after the retard kicked in... When I was testing software I had to keep resetting the ECU which also reset the learned timing retard... Hence detonation at normal advance... I believe was 18* but don't hold me to it... I was runng at 0* sometimes... It changed all the time but as soon as I put load on the engine it dropped straight to 10* retard after it learned from knock

Tom

[cdigerlando]

From the old LAN stage 3 maps it looked like timing varied from 25 to 35 degrees of advance between 4000-6500 rpm. I don't know how much you varied from this. At zero degrees of advance your EGTs should have been sky high. That is what I have noticed. Did you notice any heat damage on the pistons? I could not tell, the pics are kind of blurry.

[TomsSVX]

I was thinking that... but the pistons are all relatively sooted. None seem burned or melted except the #5 where the piece broke loose and rubbed against the piston.

One thing I want to note... I blew an engine in my old 5mt. Wasn't racing it or driving hard... just out of no where I developed a miss on my #5 cylinder. I took the engine apart and never found the cause. I know believe that one of the pistons had let go in a similar fashion but since it didn't fall apart and was held by the rings, I never noticed it. I feel that this is a problem with all pistons and will continue to be for a lot of people. SVXfiles had also lost a cylinder in a similar fashion as well. I think this is a weak point in stock pistons and as you and I have both found, under boost, it will let go. Phil... might want to keep your eyes open as well

Tom

[oab_au]

The detonation has to be from spark advance. I don't know what the spark timing was from what you say Tom. I think you are referring to the amount of timing that is pull by the knock routine.

From looking at the Pict's there was no excessive heat in the cylinder, so it was not preignition. That leaves the ignition timing, and if the map that Chuck refers to was used, it is just too much.

An engine that uses 35* advance at full throttle NA, will need a maximum advance of about 15* max. As the boost pressure goes up, the charge burns faster, less advance is needed to get maximum pressure at 15*ATDC.

You really need to cure the problem as no piston is going to last under detonation, forged or cast, if the piston survives the big end shells won't.

Harvey.;)

[TomsSVX]

i am not looking to run 12psi anymore on a stock motor. Now I am looking to drop the CR so I can run 12 psi and maybe more... 12psi is just too much and that was causing the detonation. The map was right, the motr just couldn't handle it

Tom

[oab_au]

The turboed 4 cylinder engines don't seem to have the same problem with detonation at their high boost levels.

This engine should have no problem using 14psi, if the fuel type, and spark timing is right.:)

Harvey.;)

[TomsSVX]

is the 4 cyl a 10:1 CR?? is it a twin screw blower mounted on the intake?? Realize that the charge we are send is hot and not abient and you will see why this motor cannot handle 12psi

Like I said, I was hearing audible knock at 0* of ignition...

Tom

[Trevor]

The turboed 4 cylinder engines don't seem to have the same problem with detonation at their high boost levels.

This engine should have no problem using 14psi, if the fuel type, and spark timing is right.:)

Harvey.;)

The inclusion of, "if the fuel type is right", makes the above statement completely nebulous. What is the intended point of interest? :confused:

[TomsSVX]

I have noticed that too but who really wants to run around on race fuel?? that **** is expensive!!!!;)

Tom

[oab_au]

I have noticed that too but who really wants to run around on race fuel?? that **** is expensive!!!!;)

Tom

No just normal high octane. The temp of the charge is not a problem, it is no where near the turbo temp, even with a inter cooler.

You say "I was hearing audible knock at 0* of ignition..." How do you know that the was the timing at that point. That was obversely not the total timing. As there is no way you can get knock with the spark set at TDC. the combustion volume is getting larger then.

I am not trying to start an argument, or trying to be smart, Tom, I would like to see you all have success.
I am just saying that, if you don't find and fix the problem that caused this failure, you will just send the next engine into the money pit.:eek:

Harvey.;)

[Trevor]

No just normal high octane. The temp of the charge is not a problem, it is no where near the turbo temp, even with a inter cooler.

You say "I was hearing audible knock at 0* of ignition..." How do you know that the was the timing at that point. That was obversely not the total timing. As there is no way you can get knock with the spark set at TDC. the combustion volume is getting larger then.

I am not trying to start an argument, or trying to be smart, Tom, I would like to see you all have success.
I am just saying that, if you don't find and fix the problem that caused this failure, you will just send the next engine into the money pit.:eek:

Harvey.;)

There will be no argument when statements are accurate and specific, as is expected from an "engineer". The conclusion is obvious.

[Phast SVX]

No just normal high octane. The temp of the charge is not a problem, it is no where near the turbo temp, even with a inter cooler.

You say "I was hearing audible knock at 0* of ignition..." How do you know that the was the timing at that point. That was obversely not the total timing. As there is no way you can get knock with the spark set at TDC. the combustion volume is getting larger then.

I am not trying to start an argument, or trying to be smart, Tom, I would like to see you all have success.
I am just saying that, if you don't find and fix the problem that caused this failure, you will just send the next engine into the money pit.:eek:

Harvey.;)

No were near turbo temp? oh harvey, i know you know better then to say this.....

[Phast SVX]

and of course he means ignition advance, what else would you take that for? if you wanted to make an argument, the only route would be that he is blowing out the spark.....Sorry im pissy tonight

[TomsSVX]

excuse me for the confusion. Under full retard(10*) I was actually at 8* because it should have been at 18* from what I understand. It was not actually 0* just on full retard

Tom

[cdigerlando]

The turboed 4 cylinder engines don't seem to have the same problem with detonation at their high boost levels.

This engine should have no problem using 14psi, if the fuel type, and spark timing is right.:)

Harvey.;)

Most folks who turbocharge the old pre 2002 4 cylinder RS's, which have the same or slightly lower compression, only go to about 7 or 8 psi on high octane safely. This is with a turbocharger and some are intercooled. Some folks go to 10 psi but it is shakey, unless you have forged internals. At that point most folks just lower the compression if they change out to forged internals. Check Nasioc. There is a lot of aftermarket turbo discussion. Even some supercharger discussion. I have heard of folks going to 10 psi with a turbo on our engine. That was with race fuel.

[cdigerlando]

excuse me for the confusion. Under full retard(10*) I was actually at 8* because it should have been at 18* from what I understand. It was not actually 0* just on full retard

Tom

I had major EGT trouble at this low of timing. I had to raise the timing significantly. I ran a map similar to what LAN came up with. I registered some possible predetonation noise on my logs, and slightly backed off on a couple of points, but I never seemed to have problems at this high of timing. Nothing audible. But hey, I have blowby now so who knows.

[oab_au]

I have looked back through the Supercharger thread to try to find what the ignition timing
is for the set up that TomSvx was using when Boom happened. As far as I can find.
TomSvx says it was 18*BTDC (if I read you right Tom), and the knock routine pulls 10 *
off that.

Tomfiles, says he saw 39 to 49* on light throttle (can’t believe Tom would be on light
throttle):) , don’t know if this is the same chip?. There has to be an advance problem, for
detonation to cause the second ring land to break.

I say 14lbs is attainable on this engine, but it has to be handled right. As an example, way
back in 65, when you all were kids:D , I blew a side valve engine to 14 lbs with a Roots
Blower, when the fuel octain rating was a lot lower than it is now, and the side valve
combustion chamber was far from ideal for high compression.

The way I handled it was to leave the standard spark advance, to operate as normal, till
boost came up. At 2psi the vacuum advance, acted as a vacuum retard to pull the timing
back to the 10* static setting, it stayed at this, while there was boost.. At 7lbs the water
injection started, running water into the carb throat, proportional to the boost level. I have
no idea what the output was, but at least twice as good as standard, this car did daily
duties, running the kids to school, shopping, etc. The only trouble that it had in 4 years,
was two blown head gaskets, due to the rather large circumference of the combustion
chamber.

The way I see the set up you are using, is that it does not recognise boost, working only
with, air mass through the MAF, and rpm, does not tell what is happening in the
combustion chamber. You only know if it knocks, it is too late then.

With all the modern gear that is now available to us to adjust all the inputs of fuel, spark,
and knock. It should be possible to have 14lbs as a top pressure, but adjusted to rise with
engine speed, starting at 2000 rpm, say 5lbs, to rise to 14 by 3500 rpm.
An engine can use more boost pressure as the rpm rises. Too much at low rpms will
detonate heavily due to the time that the piston contains the combustion chamber steady,
while combustion pressure increases rapidly.

The one all saving action that can be taken is to inject water. There is absolutely no
chance of detonation when water is used properly. I think a MAP sensor should be used
to recognise boost, and the spark and water controlled off that, instead of relying on the
MAF and rpm. I know Lan, wants to keep the MAF as the one, to base the fuel on, so it
can still be used for that, the MAP can just be for the spark correction and water injection.
He has an extra switchable map for 87 octane. This map could be a boost map that the
MAP sensor could switch to when boost is detected.

Harvey.;)

[Trevor]

The way I handled it was to leave the standard spark advance, to operate as normal, till boost came up. At 2psi the vacuum advance, acted as a vacuum retard to pull the timing back to the 10* static setting, it stayed at this, while there was boost.
:confused: :confused: :confused:

The way I see the set up you are using, is that it does not recognise boost, working only with, air mass through the MAF, and rpm, does not tell what is happening in the combustion chamber. You only know if it knocks, it is too late then.

Surely “air mass through the MAF”, must translate too boost pressure. Is not the the specific object of forced induction, to increase the mass of the air flow, over a given lengthy of time?

What is more, likewise the signal also translates the amount of charge induced into the cylinder, to become compressed within combustion the chamber; i.e. all of that, other than ignition and fuel values, which is involved in detonation.

[TomsSVX]

but why? I mean, you are spending 7500 on a S/C kit to run 9psi. If you want more power, build a motor for more power. I have never been affectionate to band-aide solutions such as water injection and that why I never put my injection kit on the car. If you want to make real power, make a real motor. Harvey, seriously take a look at a piston from and EG33 and you will see why the second land broke... I couldn't believe how thin the material is on the top/bottom of the piston(if it is laying in the motor) Just looking at them wrong could break it:rolleyes: Thats is why I am going with beter pistons. The lower end is getting built to handle more power because... why would you build a suspension bridge to hold it's minimum weight?? You build it to hold more in the event the weight is exceeded and just for safe measure. The heads are going to be built because we cannot clear the combustion chamber quickly enough with the cams we have AND/OR we are experiencing valve float... There should be no reason for a MAP since boost should be programed. If you are at a certain throttle at a certain RPM... you will make X amount of pressure or vacc. With a PD blower it is constant which makes it much easier to tune than say a turbo car

Tom

[Trevor]

The one all saving action that can be taken is to inject water.
There is absolutely no chance of detonation when water is used properly.

Here is a definitive statement which firstly, runs against recorded history, and secondly is not correct. If the statement was true, water injection in one of the many forms so far attempted, would be to the forefront of automotive design.

In point of fact, the process has in the main, been limited to hobby applications; several concerns over many years, having promoted the idea along with sets of components. I have friend who spent untold hours, before disbanding such a project, as have many others.

A major problem still to be solved, involves a reliable arrangement which will automatically shut off the water, shortly before each and every time the engine is stopped. Without this feature, residual moisture has been proven to cause real damage, through corrosion. Rings and valves in particular being badly affected.

Harvey, all here will be interested to learn as to exactly how you overcame this problem, even though it has perplexed and defeated others. :confused:

[cdigerlando]

Here is a definitive statement which firstly, runs against recorded history, and secondly is not correct. If the statement was true, water injection in one of the many forms so far attempted, would be to the forefront of automotive design.

In point of fact, the process has in the main, been limited to hobby applications; several concerns over many years, having promoted the idea along with sets of components. I have friend who spent untold hours, before disbanding such a project, as have many others.

A major problem still to be solved, involves a reliable arrangement which will automatically shut off the water, shortly before each and every time the engine is stopped. Without this feature, residual moisture has been proven to cause real damage, through corrosion. Rings and valves in particular being badly affected.

Harvey, all here will be interested to learn as to exactly how you overcame this problem, even though it has perplexed and defeated others. :confused:


I run water injection. It comes on when boost is sensed. It is not going to "cure" detonation. Only reduce it. It might be possible to tune the car with forged pistons at 10:1 compression and low to medium boost. But why would I not drop to 8.5:1 when I'm installing custom pistons. It would be a great experiment, but a bit too expensive.

[Tim]

Are you still running the magnaflow setup or did you change it to a true dual now?

[Phast SVX]

Are you still running the magnaflow setup or did you change it to a true dual now?

I hope you dont mean Cdiger? its turbocharged???

[TomsSVX]

nah Tim... its still the magnaslows... I will be whipping up a new system in the spring hopefully.

Tom

[oab_au]

Sorry Tom,:)
I am not just directing this at you only. I know you will do what ever you want,:D I am
thinking of other people that want to try, or are trying to force induct the
EG33.
There is a difference in the way combustion is handled between the Naturally Aspirated,
and Supercharged engine. The big difference is knock, on our engine in NA form, at full
throttle 5000 rpm, we have a combustion chamber trapped pressure of 1.636 bar/24psi,
the temp of the charge is 119*C. The ignition advance in this case would be about
35/37*BTDC. and the maximum pressure developed in the chamber during the burn is
71.4 bar/1050psi, and will occur at 17* ATDC. The combustion chamber and piston
crown temp will be 358*C.

Now if we run a inlet maifold pressure of 1bar, the above pressures and temperatures will
double, and the burn time will almost halve. We still need the maximum pressure to be at
17*ATDC, so we will have to start the burn later, by reducing the ignition advance, to
have the maximum pressure arrive at the same 17*ATDC.

Now this can be done by dynoing the engine and setting the timing advance to suit each
operating condition for Air flow X rpm. But, it only takes a load of bad fuel, a very hot air
day, or a slight engine overheat, valve bounce, exhaust backflow on ovelap etc. for it to
step out of the mapped
conditions line, and detonation takes it all out.

When detonation takes place, in an engine operating under these boosted conditions, it is
unfortunately too late to save the engine. The same knock that the sensors hears, breaks
the top rings, or in this case also shearing off the second ring land. When the engine has
this much pressure in the chamber, there is no second chance, like there is, when it is NA
and the detonation pressure is much lower.

Detonation, is the spontaneous, uncontrolled combustion, of part or all of the compressed
charge, after the spark has started a burn. What happens is the spark lights the charge, the
flame front burns out away from the plug, As the flame front advances across the
chamber, the gas that is furthest away from the plug in the exhaust side, is increasing in
temperature, from the radiated heat, and pressure from the expanded gas already burnt.
This gas reaches its flash point, and explodes, this sudden rise in pressure, hammers the
top ring, the piston and the bearings. When detonation is on, the piston usually breaks,
and the rod is let go, to do its own thing.:eek:

We can do a number of things to prevent this. Use a fuel that can withstand the pressure
and temp (higher octane), because of its higher flash point, We can reduce the
temperature of the gas charge with an intercooler. Or combustion chamber, using a fuel
like Alcohol.

Or we can use water injection.:)

Water injection is not a new band-aid,:rolleyes: it was used extensively in the
development of aircraft engines during the 2WW. In Sir Harry Ricardo’s Book “ THE
HIGH SPEED INTERNAL-COMBUSTION ENGINE” That every body has on their
shelf.;) (under ’Supercharging’ or Google supercharge+water+injection.)
He relates the development of a supercharged aircraft engine that reached detonation at a
BMEP of 168psi. Fuel enrichment was increased ( up to 60%) to allow further boost, to
achieve a BMEP of 238 psi. when detonation again occurred. A fine stream of misted
water was then sprayed into the inlet, and the boost pressure increased till detonation
occurred, to reach a BMEP of 290 psi.

In the example that I did on the sidevalve. I had detonation starting at 8psi. This would
have been my limit, without dropping the compression ratio,( which reduces the off boost
performance:( ) or using a better fuel.(too dear). But with the water starting at 7psi, I was
able to increase the boost to 14psi. without any risk of detonation. You can introduce the
water in a few ways, mixed with the fuel(using Acetone), but as it is only needed when it
is on boost, its is better to introduce it into the inlet tract, to cool the charge, and the
combustion chamber, the resultant steam suppresses detonation.

There are a number of water kits on the market, I would look for one that can spray the
water, proportional to boost, as too much water will drop power. You just need enough to
suppress detonation. The best would be able to use the blower’s by-pass, to control boost
at low rpms, and proportionally spray water to suit the boost.

The way I did it back then, was to have the manifold pressure applied to a container of
water, when the boost reached the 2psi, it opened a one-way valve to flow to the carb,
proportionally to the boost pressure acting on it. When the engine was on vacuum it
sucked water up from a tank in the boot to top up the front tank. Oldies will recognise this
as the ‘Vacuum fuel tank’ that we used to bring fuel up to the engine in the 20s.:D
:rolleyes:

The numbers used in this post, are for example only, they are in the range, for these
conditions.

Harvey.;)

[longassname]

One of the axis of the timing maps is load. Load whether measured by manifold pressure or calculated from the mass of air measured and rpm equates to the same thing. Mass air measurements are more accurate actually. There do seem to be some mechanical limitations to running higher boost. Whether just because of 150,000 miles of wear or because the ring set up isn't optimal for forced induction or a combination of both there is obviously a problem with blow by.

We can probably improve the tuning at higher loads as well. My personal feeling is that these 150,000 mile factory engines obviously aren't happy with a lot of boost so we aught to go ahead and build the engines appropriately for what we want...which we are doing...and to do our higher load tuning on these engines. It seems kind of pointless to try and run high boost on worn out motors. It will be easier for me to tune the high loads when I don't have exhaust flow problems and fluttering rings confounding my measurements anyway.

[cdigerlando]

One of the axis of the timing maps is load. Load whether measured by manifold pressure or calculated from the mass of air measured and rpm equates to the same thing. Mass air measurements are more accurate actually. There do seem to be some mechanical limitations to running higher boost. Whether just because of 150,000 miles of wear or because the ring set up isn't optimal for forced induction or a combination of both there is obviously a problem with blow by.

We can probably improve the tuning at higher loads as well. My personal feeling is that these 150,000 mile factory engines obviously aren't happy with a lot of boost so we aught to go ahead and build the engines appropriately for what we want...which we are doing...and to do our higher load tuning on these engines. It seems kind of pointless to try and run high boost on worn out motors. It will be easier for me to tune the high loads when I don't have exhaust flow problems and fluttering rings confounding my measurements anyway.

Agreed! Age, high compression, forced induction, weak pistons.....bad. Sorry to not be more technical.

[mikecg]

One of the axis of the timing maps is load. Load whether measured by manifold pressure or calculated from the mass of air measured and rpm equates to the same thing. Mass air measurements are more accurate actually. There do seem to be some mechanical limitations to running higher boost. Whether just because of 150,000 miles of wear or because the ring set up isn't optimal for forced induction or a combination of both there is obviously a problem with blow by.

We can probably improve the tuning at higher loads as well. My personal feeling is that these 150,000 mile factory engines obviously aren't happy with a lot of boost so we aught to go ahead and build the engines appropriately for what we want...which we are doing...and to do our higher load tuning on these engines. It seems kind of pointless to try and run high boost on worn out motors. It will be easier for me to tune the high loads when I don't have exhaust flow problems and fluttering rings confounding my measurements anyway.




So when we ordering some parts already???...... Money + Pocket = 5 alarm fire. ;)

[GreenMarine]

Tom, how did you destroy that engine??

Also, I am curious (probably has been answered already though :rolleyes: ) How much power can that supercharger kit produce reliably on an engine with around 100k miles??

[mikecg]

I'm getting 229whp and 243wtq at a safe 9lbs of boost. with 68K miles on it.


http://www.subaru-svx.net/photos/files/mikecg/39932.jpg


The higher numbers are Toms car at 12lbs boost and the lower is mine with 9lbs boost. The main difference between Toms car and mine is that I was running 2 1/2in duals all the way out.

[Trevor]

Agreed! Age, high compression, forced induction, weak pistons.....bad. Sorry to not be more technical.

Absolutely no need. Your confirmation will be well received I am sure. However being contiually told how to suck eggs, and badly, is another thing :eek:

These guys obviously know what they are doing, as per the evidence from them confirming a sound logical approach.

[Phast SVX]

Absolutely no need. Your confirmation will be well received I am sure. However being contiually told how to suck eggs, and badly, is another thing :eek:

These guys obviously know what they are doing, as per the evidence from them confirming a sound logical approach.


yes.....that logical approach thing..... im sure someday i will run that route, but its just too much damn fun grabbing a 12 pack and a tig!

[Trevor]

yes.....that logical approach thing..... im sure someday i will run that route, but its just too much damn fun grabbing a 12 pack and a tig!

I would say that if this gives you enjoyment, It IS logical.:)

[longassname]

Well I'm back now. I'm guessing my sample piston is waiting for me at the dealership so we can order pistons this next week. I'll probably be getting my cams ground next week too but I won't be ready to order the cam package for others until after I've gotten my cams ground and am ready to order the valves. I have to actually get the cams ground before I know exactly how much the base circle is reduced so I can order the valves. I already have several sets of springs in stock.

So when we ordering some parts already???...... Money + Pocket = 5 alarm fire. ;)

[cdigerlando]

Well I'm back now. I'm guessing my sample piston is waiting for me at the dealership so we can order pistons this next week. I'll probably be getting my cams ground next week too but I won't be ready to order the cam package for others until after I've gotten my cams ground and am ready to order the valves. I have to actually get the cams ground before I know exactly how much the base circle is reduced so I can order the valves. I already have several sets of springs in stock.

Will you be testing the pistons before finishing your topend work? If anyone else is interested I will be sending off my heads to have copper gaskets made. Is anyone else interested, or is this something that you are doing? If so, I'm in with that too.

[longassname]

I'm just going to build one engine complete with rods, pistons, and the cam set so it will all be tested together. I was going to test the cam set on a stock bottom end to get some good dyno numbers for the na guys but that's too much time and money for no return. I'm going to use the factory head gaskets in my build.

[cdigerlando]

I'm just going to build one engine complete with rods, pistons, and the cam set so it will all be tested together. I was going to test the cam set on a stock bottom end to get some good dyno numbers for the na guys but that's too much time and money for no return. I'm going to use the factory head gaskets in my build.

That is probably a good idea. I'm assuming you are also going to test the new valve train?

[longassname]

the valves are part of the cam set...one doesn't work without the other.


That is probably a good idea. I'm assuming you are also going to test the new valve train?

[TomsSVX]

I'm in for a set of copper hg's. They should be able to withstand the vibrations better than stockers. Count me in if you are getting them made

Tom

[cdigerlando]

the valves are part of the cam set...one doesn't work without the other.

Excellent.

[cdigerlando]

I'm in for a set of copper hg's. They should be able to withstand the vibrations better than stockers. Count me in if you are getting them made

Tom

I'll keep you posted on a cost. I need to ship them some stock gaskets. Do you have any in fairly decent shape we could send to them? I'm going to also need to ship my heads. Do you know if they are exactly symmetrical?

[nico i wrx u]

i have a question, is the eg33 motor closed deck? does it have oil squirters also?

i am pulling the motor and i read some where i could stick ej22t pistons in it is this true? if it is true then i could also order 2004 sti 550cc injectors and drop them in as well.

[TomsSVX]

do some searching.. the ej22 pistons will not function well at all. the injectors are not bolt in's either.

Chuck, I will see if I still have my new HG's laying around from an old kit. I know Mikecg was also talking about getting some copper hg's made

Tom

[oab_au]

One of the axis of the timing maps is load. Load whether measured by manifold pressure or calculated from the mass of air measured and rpm equates to the same thing. Mass air measurements are more accurate actually. There do seem to be some mechanical limitations to running higher boost. Whether just because of 150,000 miles of wear or because the ring set up isn't optimal for forced induction or a combination of both there is obviously a problem with blow by.

We can probably improve the tuning at higher loads as well. My personal feeling is that these 150,000 mile factory engines obviously aren't happy with a lot of boost so we aught to go ahead and build the engines appropriately for what we want...which we are doing...and to do our higher load tuning on these engines. It seems kind of pointless to try and run high boost on worn out motors. It will be easier for me to tune the high loads when I don't have exhaust flow problems and fluttering rings confounding my measurements anyway.



One of the axis of the timing maps is load. Load whether measured by manifold pressure or calculated from the mass of air measured and rpm equates to the same thing. Mass air measurements are more accurate actually.

Yes Mike, I agree that the MAF is the better sensor, to determined the fuel needs, but it cannot tell if that air is being used in a 5lt NA engine, or a 3.3lt supercharged engine. By relying only on this air flow to determine the ignition timing, it cannot tell the pressure conditions, in the combustion chamber, which will be vastly different between the two engines. It is to suit these conditions, that the ignition timing has to satisfy.

There do seem to be some mechanical limitations to running higher boost. Whether just because of 150,000 miles of wear or because the ring set up isn't optimal for forced induction or a combination of both there is obviously a problem with blow by.

The engine has been able to handle high loads of Nitrous, ‘mainly’ without problems. This is due to the lack of detonation, that Nitrous can reduce. The problem is DETONATION, and no engine, no matter how much money is spent, or how stronger the pistons are, detonation will still break them.

It will be easier for me to tune the high loads when I don't have exhaust flow problems and fluttering rings confounding my measurements anyway.

Yes you can spend time on a dyno to setup the ignition timing, to suit that particular engine, but every engine that runs that timing map, has to be exactly the same as the test engine. Any operating condition that varies from that test engine, which includes just about thing you can think of, air temp, engine temp, exhaust, bad fuel, etc,etc.will be at risk of detonation destruction. The conditions in the dyno room, maybe a lot different to a full throttle run through the deserts of Aust.:)

When I talked about using a MAP sensor, I did not mean to substitute the MAF sensor. I was suggesting using a pressure sensor/switch to signal the start of boost. An adjustable pressure switch, to switch your ignition timing Map to a retarded boost Map, that will protect the engine from straying into the detonation, danger area.

Anyway, I can see I am not get through, so I will leave you to it. All the best.:)

Harvey.;)

[TomsSVX]

Harvey, do you realize these pistons are going to lower the compression ratio? they are not just stronger. If you paid enough attention to what people are saying, Chuck never had audible knock yet his motor went the way of the dodo in the same or similar fasion mine had. I am sure if I keep running my 9psi system as hard as I do, I will blow this motor out of the water as well. There is a weak point in the pistons that do not like excess power. I blew one in my old Ebony, svxfiles blew one in his s/c car, I blew 4 in my silver, and chuck lost at least one as well.... Is it sinking in yet?

Tom

[Trevor]

Yes Mike, I agree that the MAF is the better sensor, to determined the fuel needs, but it cannot tell if that air is being used in a 5lt NA engine, or a 3.3lt supercharged engine. By relying only on this air flow to determine the ignition timing, it cannot tell the pressure conditions, in the combustion chamber, which will be vastly different between the two engines. It is to suit these conditions, that the ignition timing has to satisfy.

Harvey.;)

A very strange statement indeed.

“It” WILL be able to tell the pressure conditions in any particular combustion chamber, because “it” will be “told” by the designer the kind of engine with which “it” will be required to function. “It” does not require a selective brain.:rolleyes:

Yes you can spend time on a dyno to setup the ignition timing, to suit that particular engine, but every engine that runs that timing map, has to be exactly the same as the test engine. Any operating condition that varies from that test engine, which includes just about thing you can think of, air temp, engine temp, exhaust, bad fuel, etc,etc.will be at risk of detonation destruction. The conditions in the dyno room, maybe a lot different to a full throttle run through the deserts of Aust.:)


It is being in affect stated, that a mean set of figures can not be established, so as to be suitable for an average set of conditions. If so, no production engine could exist. Agreed that forced induction presents a somewhat more critical problem. However this has not prevented successful production examples. :confused:

[oab_au]

Harvey, do you realize these pistons are going to lower the compression ratio? they are not just stronger. If you paid enough attention to what people are saying, Chuck never had audible knock yet his motor went the way of the dodo in the same or similar fasion mine had. I am sure if I keep running my 9psi system as hard as I do, I will blow this motor out of the water as well. There is a weak point in the pistons that do not like excess power. I blew one in my old Ebony, svxfiles blew one in his s/c car, I blew 4 in my silver, and chuck lost at least one as well.... Is it sinking in yet?

Tom


I'm sorry Tom, but don"t under stand what I am saying.:)

There is a weak point in the pistons that do not like excess power.


But it is ok if its Nitro.:rolleyes:

Anyway no problem. I'm off.:)

Harvey.;)

[nico i wrx u]

i did a search, o well im just going to have to rip out the motor and see what i have, im going to try stick the ej22t pistons in eg33 i got five ej22ts lying around lots of pistons still in good shape.

also sti 2004 injectors fit in the rials no problems who told you they didnt fit tom?

[Trevor]

I'm sorry Tom, but don"t under stand what I am saying.:)



But it is ok if its Nitro.:rolleyes:

Anyway no problem. I'm off.:)

Harvey.;)

Harvey, YOU do not understand what Tom is continually indicating. He IS aware of all that you have posted, but is brassed of with your patronisation. .:p

[mikecg]

I'll keep you posted on a cost. I need to ship them some stock gaskets. Do you have any in fairly decent shape we could send to them? I'm going to also need to ship my heads. Do you know if they are exactly symmetrical?


I'm interested in the gaskets, also. If Tom cant find any gaskets, I have a set of gaskets on order. It should be here in a week or two. I have my engine completely disassembled and ready to ship out. I just need to find a machine shop to send everything too. Anyone go a number for ESX, so I can send the block and heads to have them work them? :D

[SVXRide]

I'm also interested in the head gaskets.:cool:
-Bill

[cdigerlando]

I'm interested in the gaskets, also. If Tom cant find any gaskets, I have a set of gaskets on order. It should be here in a week or two. I have my engine completely disassembled and ready to ship out. I just need to find a machine shop to send everything too. Anyone go a number for ESX, so I can send the block and heads to have them work them? :D

Mike:

I will get back in touch with Gasket works and see what kind of a deal they can give us for 3 pairs of gaskets. I still need to pull my engine. As for your head work, I was kind of hoping that LAN was going to offer the work. He was also looking at a light port and polish I belive. I would definitely prefer he did this than someone else. I may end up doing the bottom end locally, because I want to use his pistons with his valves. Only problem is I'll probably be 3rd (or more) in line behind you good S/C customers.

Harvey:

I think you bring up some good points. Especially the comparison between Nitrous and FI. It may be possible that the nitrous is a much cooler running system than the FI. This may have affected the stress on the pistons. I really don't know. As for detonation, I have a detonation sensor mounted to my motor and connected to my Tec II. If I sensed any predetonation (not audible) I backed off on the timing. The tec II also uses manifold pressure, temperature, rpm, and volumetric efficiency to calculate fuel and air flow. I never had any fuel starving going on. Always running rich. I also run water injection, which comes on the minute my manifold pressure goes over atmospheric pressure. Trust me we have tried.

Tom is very patient. He said has destroyed 5 motors? It is time to move on and try something different. I am worred about the next stage from a cooling standpoint, and hope that it works out for us. I do enjoy your input and hope that you continue to monitor our progress.

Take Care

[TomsSVX]

But it is ok if its Nitro.:rolleyes:
Harvey.;)

Nitrous is not run all the time... Pur cars are contantly under boost and pressure while nitrous has ver limited use... notice that my engine held up for 10k miles on 12psi? run nitrous for 10kmiles and let me know where your motor is at:rolleyes:

Tom

[mikecg]

Mike:

Only problem is I'll probably be 3rd (or more) in line behind you good S/C customers.

Take Care


I dont think you'll have to wait any ionger then the rest of us. LAN isnt producing the pistons in house. He'll be ordering them from another company, and will want as many people to get in on a order as possible. The larger the order he can put together the cheaper the individual price will be. Now as far as the CAMS and valves go I'm not to sure how he pans on doing that. I spoke to him earlier today. He's a little behind on things, but the piston came in and he's going to try and get it out to the manufacturer this week. I'd expect him to post in the next 2 weeks or so to put together a group order with us. I know he cant order the valves until the Cams are made and he makes some measurements off of them.

[mikecg]

Nitrous is not run all the time... Pur cars are contantly under boost and pressure while nitrous has ver limited use... notice that my engine held up for 10k miles on 12psi? run nitrous for 10kmiles and let me know where your motor is at:rolleyes:

Tom


Now, Now Tom lets be truthful. The supercharger is in by-pass when your at idle, and cruising. Of course the only time I'm cruising or idling is while I'm waiting to line up at the tree, or traveling to/from the track. :D

[TomsSVX]

yeah... my point exaclty

Tom

[SVXRide]

595.5 g (thanks Ron!)...so they're ~65g heavier than the Eagle rods (which means the Eagle rods are ~90g lighter than the stock rods!)
-Bill

[longassname]

I guess i'll start a piston thread pretty soon. I guess here is as good as anywhere to say all those who want to order pistons in the first batch get ready to order. We will be ordering them sometime this week.

[cdigerlando]

I guess i'll start a piston thread pretty soon. I guess here is as good as anywhere to say all those who want to order pistons in the first batch get ready to order. We will be ordering them sometime this week.

I'm in for pistons.

Mr. Gasket requested a photo of a head gasket. He may have a template for this already. If anyone has a complete photo or can point me in the correct direction, I would greatly appreciate it.

Thanks

Chuck D.

[mikecg]

I'm in for pistons.

Mr. Gasket requested a photo of a head gasket. He may have a template for this already. If anyone has a complete photo or can point me in the correct direction, I would greatly appreciate it.

Thanks

Chuck D.


I have a photo posted in my public folder, in the "Engine Build up" folder (warning, large picture). Both sides appear to be identical.

[Crazy_pilot]

*Looks at pics*....Do you seriously have a pet peacock?

[Phast SVX]

I'm in for pistons.

Mr. Gasket requested a photo of a head gasket. He may have a template for this already. If anyone has a complete photo or can point me in the correct direction, I would greatly appreciate it.

Thanks

Chuck D.

One of these days you need to just drive up and we will intercool your setup in a weekend. You seem as though you want to go that direction and I am not gonna lie, i would like to fab some stuff, getting the itch.

phil

[cdigerlando]

I have a photo posted in my public folder, in the "Engine Build up" folder (warning, large picture). Both sides appear to be identical.

Thanks. I'll send it to Mr. Gasket and let you know if they have the template.

[cdigerlando]

One of these days you need to just drive up and we will intercool your setup in a weekend. You seem as though you want to go that direction and I am not gonna lie, i would like to fab some stuff, getting the itch.

phil

I would love to. Too bad you live in Wisconsin. I was actually planning to do this next before I started getting blowby. It is the first thing I will do after rebuilding the engine. That and increasing the exhaust size to 3". Thanks for the offer.

[mikecg]

*Looks at pics*....Do you seriously have a pet peacock?


LOL, He was never really a pet. He just showed up one day. He hung around for about 6 months then just left one day.