Boom Baby!!! - Page 3

SVXRide · #31 01-25-2007, 06:29 PM

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

-Bill

longassname · #32 01-25-2007, 08:45 PM

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

SVXRide · #33 01-25-2007, 09:53 PM

Quote:

Originally Posted by longassname

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

Good question....Calling NeedForSpeed....Calling NeedForSpeed

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

TomsSVX · #34 01-26-2007, 12:39 PM

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

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 · #35 02-05-2007, 09:36 AM

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 · #36 02-05-2007, 10:01 AM

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 · #37 02-05-2007, 11:22 AM

Quote:

Originally Posted by 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

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 · #38 02-05-2007, 11:39 AM

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 · #39 02-05-2007, 01:25 PM

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 · #40 02-05-2007, 01:50 PM

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

oab_au · #41 02-05-2007, 02:34 PM

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 · #42 02-05-2007, 05:42 PM

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 · #43 02-06-2007, 09:26 AM

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 · #44 02-06-2007, 12:07 PM

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 · #45 02-06-2007, 04:33 PM

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.