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  #46  
Old 08-04-2012, 08:15 PM
oab_au oab_au is offline
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Re: Camshafts for the EG33.

Quote:
Originally Posted by bazza View Post
Some good theory there guys.

Out of interest Harvey, have you got a built EG33 sitting in your shed with this theory applied?
Yes I do Bazz, it is a stock 95, it has a wide, strong torque curve that Subaru has used, that is centered the torque on the usable speed range that the car is designed to do. It does this service very well, I have no need to change it.
My need to build engines for other uses, has diminished as my capacity to do it has, but I have leaned a lot over those 50 odd years in Auto Engineering and like to assist those that are doing it now. I leave the building to my son, who you may meet one day at Wakefield Pk. with a Peugeot 306, with a mid mounted turboed 4lt Toyota V8.

Quote:
I find a lot of people love to give advice based on sound theory but very few of those people have actually put their own hard earned money into what they theorise about and fewer have proven results. I imagine you will have and I'd be interested in what it's running etc.
I don't have to actually do the build on this engine to prove that the theory is sound, I have used it on many bike engines both two and four stroke and have found it to be well founded. As it is a lot cheaper to build a single cylinder engine to do the R and R. Now I only have to use a Lotus Engineering program to do all the engine cylinder work, I can try different timings, lifts, track lengths, to get the torque curve that the engine will need to do the work that it will have to do.
I will apply this theory to Tony's engine to get the best usably result.
Cheers and beers.

Harvey.
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  #47  
Old 08-05-2012, 09:02 AM
bazza bazza is offline
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Re: Camshafts for the EG33.

Quote:
Originally Posted by oab_au View Post
Yes I do Bazz, it is a stock 95, it has a wide, strong torque curve that Subaru has used, that is centered the torque on the usable speed range that the car is designed to do. It does this service very well, I have no need to change it.
My need to build engines for other uses, has diminished as my capacity to do it has, but I have leaned a lot over those 50 odd years in Auto Engineering and like to assist those that are doing it now. I leave the building to my son, who you may meet one day at Wakefield Pk. with a Peugeot 306, with a mid mounted turboed 4lt Toyota V8.

I don't have to actually do the build on this engine to prove that the theory is sound, I have used it on many bike engines both two and four stroke and have found it to be well founded. As it is a lot cheaper to build a single cylinder engine to do the R and R. Now I only have to use a Lotus Engineering program to do all the engine cylinder work, I can try different timings, lifts, track lengths, to get the torque curve that the engine will need to do the work that it will have to do.
I will apply this theory to Tony's engine to get the best usably result.
Cheers and beers.

Harvey.
I have no doubt the theory is good. I was just hoping you had an EG33 with cams etc. Bike engines give you a good idea but at the end of the day they still only give you a good idea and from that you still need to build an EG33 and spend time testing to find out if the theory is on the money or not. On the other hand Jack's EG33 gives us some brilliant results to go by - it's good proper old fashion proven theory... which is my type of theory. Unfortunately in the turbo EG33 land there isn't a lot of proven setups so I'm relying on my EJ2X experience which is proving nicely thus far.

P.S. Are you able to stick the stock engine into your computer and see what it comes up with at 10 / 15 psi with the stock manifolds. Would be interested to see how close it is to reality. Turbo is a GT35R, from here: http://www.turbobygarrett.com with a 0.82 rear.

Last edited by bazza; 08-05-2012 at 09:05 AM.
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  #48  
Old 08-06-2012, 06:07 PM
bazza bazza is offline
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Re: Camshafts for the EG33.

Cams in the mail today to my shop, will keep you posted on progress. Can't wait
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  #49  
Old 08-06-2012, 06:11 PM
dynomatt dynomatt is offline
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Re: Camshafts for the EG33.

Let us know when you decide on a profile.

M
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  #50  
Old 08-06-2012, 06:16 PM
bazza bazza is offline
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Re: Camshafts for the EG33.

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Originally Posted by dynomatt View Post
Let us know when you decide on a profile.

M
Will do mate. Thanks for your advice also.

Some great info here:
http://www.tighecams.com.au/helpful-hints.htm

Good selection of cams:
http://kelfordcams.com/applications.aspx

Last edited by bazza; 08-07-2012 at 08:40 AM.
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  #51  
Old 08-20-2012, 08:10 AM
bazza bazza is offline
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Re: Camshafts for the EG33.

Matt, my mate sent over the info about his EG33 billet cams. Massive duration!!

Intake:
318 duration (advertised)
235 duration @ 50 thou
9.9mm lift

Exhaust:
339 duration (advertised)
235 duration @ 50 thou
10.0mm lift

P.S. My cams still at shop... waiting... always waiting.
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  #52  
Old 08-20-2012, 12:11 PM
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RallyBob RallyBob is offline
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Re: Camshafts for the EG33.

Quote:
Originally Posted by bazza View Post
Matt, my mate sent over the info about his EG33 billet cams. Massive duration!!

Intake:
318 duration (advertised)
235 duration @ 50 thou
9.9mm lift

Exhaust:
339 duration (advertised)
235 duration @ 50 thou
10.0mm lift

P.S. My cams still at shop... waiting... always waiting.
In truth those are quite tame camshafts. They have very gentle valve openings judging by the relationship between the advertised duration and the @ .050 duration numbers. The advertised numbers don't tell the whole story.

An aggressive cam profile will tend to have faster valve openings and closings. Jack's cams by comparison have 244 @ .050 duration but with 268 advertised duration. VERY fast opening and closing ramps with very rapid valve acceleration.
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  #53  
Old 08-20-2012, 05:39 PM
bazza bazza is offline
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Re: Camshafts for the EG33.

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Originally Posted by RallyBob View Post
In truth those are quite tame camshafts. They have very gentle valve openings judging by the relationship between the advertised duration and the @ .050 duration numbers. The advertised numbers don't tell the whole story.

An aggressive cam profile will tend to have faster valve openings and closings. Jack's cams by comparison have 244 @ .050 duration but with 268 advertised duration. VERY fast opening and closing ramps with very rapid valve acceleration.
Out of interest, why would one want the valves to open as quickly as possible - does it help with the NA applications? Would such an aggressive opening take long to damage the seats and or valves?

I've spoken again with the guys about my cams this morning, looks like they'll be able to do something along the lines of 220 @ 50 with around 8.1mm intake and 8.9 mm exhaust. It should be just enough of an increase to get the engine to where I want it performance wise which is to flow to 6500-7000 rpm and not drop off at 10-14 psi (although at 14 psi ti didn't drop off... it hit a brick wall!). Thanks to LAN for his assistance and guidance with these. Funnily enough on the Kelford site, this type of duration and lift cam is good enough for a 4 cylinder EJ to see 8000 rpm... good sign.

Already thinking of version 2 of my cam regrind... I've still got 2 spare sets of stock cams to play with and given how easy they are to remove, could swap and change to suit different tracks if I ever wanted to (assuming the regrinds all go to plan):
http://www.subaru-svx.net/forum/showthread.php?t=54965


Also my other mate has just installed his EG33 into his RS Liberty. He had some cams done as well - however it would seem these have been welded as the lobe heights have increased. One of my other mates in the mean time has scored an epic picked up a perfectly good eBay EZ30R on ebay for $1250 for his Impreza... fun times, H6 FTW!!!!

But anyway... cam stuff for the RS Liberty EG33:


Inlet: 255 deg advertised
Exh: 265 deg advertised
Duration @ 0.50 thou
Inlet: 199 deg
Exh: 215 deg

Lobe centre:
Inlet: 112 deg
Exh: 116 deg

Intake lobe height 39.97 (39.1 stock)
Base circle 31.61
Inlet: 8.4mm

Exhaust lobe height 40.25 (39.9 stock)
Base circle 31.71
Exh: 8.5mm

This car will run NA mode for a while until he gets around to putting a turbo on - so the results will be very interesting.

Last edited by bazza; 08-20-2012 at 11:08 PM.
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  #54  
Old 08-21-2012, 08:38 AM
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RallyBob RallyBob is offline
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Re: Camshafts for the EG33.

Quote:
Originally Posted by bazza View Post
Out of interest, why would one want the valves to open as quickly as possible - does it help with the NA applications? Would such an aggressive opening take long to damage the seats and or valves?
The longer the valves stay on the seats, the longer time you have to build cylinder pressures. A super-long seat-to-seat duration cam is essentially always bleeding off pressure. Bad enough (at low rpms) in an N/A application, but applying boost while simultaneously leaking combustion pressures seems counterproductive...

So while we do want enough duration (and therefore overlap) to aid in scavenging and help the engine to make power in the upper realm, too much overlap can also be bad, particularly with forced induction.

Yes, there is a fine line between fast opening/fast closing and increased engine wear. The cam specs you've quoted would likely be very gentle on the valves and seats. Less spring tension could be run in fact, as valve bounce would likely be non existant

As a rule, most hydraulic profiles are far more gentle than mechanical profiles (except for the intial 'takeup' designed to eliminate the valve lash in a gentle fashion), as the hydraulic buckets can't cope with modern (race oriented) fast acting lobe profiles. They will simply collapse.
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  #55  
Old 08-21-2012, 08:58 AM
bazza bazza is offline
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Re: Camshafts for the EG33.

Quote:
Originally Posted by RallyBob View Post
The longer the valves stay on the seats, the longer time you have to build cylinder pressures. A super-long seat-to-seat duration cam is essentially always bleeding off pressure. Bad enough (at low rpms) in an N/A application, but applying boost while simultaneously leaking combustion pressures seems counterproductive...

So while we do want enough duration (and therefore overlap) to aid in scavenging and help the engine to make power in the upper realm, too much overlap can also be bad, particularly with forced induction.

Yes, there is a fine line between fast opening/fast closing and increased engine wear. The cam specs you've quoted would likely be very gentle on the valves and seats. Less spring tension could be run in fact, as valve bounce would likely be non existant

As a rule, most hydraulic profiles are far more gentle than mechanical profiles (except for the intial 'takeup' designed to eliminate the valve lash in a gentle fashion), as the hydraulic buckets can't cope with modern (race oriented) fast acting lobe profiles. They will simply collapse.
Bob, just so you know, that long duration cam profile is the one for my mates solid Supertech bucket setup, not hydraulics. My setup is the one staying with the hydraulics because it's cheaper, easier and it means I can spend budget elsewhere on the car whilst sacrificing a little power etc.

Also thanks, good to know about the differences.
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  #56  
Old 08-22-2012, 08:46 PM
bazza bazza is offline
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Re: Camshafts for the EG33.

Okay, excitement to the max!!

Regrind specs, being ground up now:

Inlet:
270 advertised
220 @ 50 thou
7.9mm lift

Exhaust:
275 advertised
220 @ 50 thou
8.7mm lift

So some improvements across the board - should do the trick
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  #57  
Old 08-23-2012, 06:21 PM
oab_au oab_au is offline
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Re: Camshafts for the EG33.

Did they say what the valve timings, or lobe centers, would be.?

Harvey.
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  #58  
Old 08-24-2012, 03:02 AM
bazza bazza is offline
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Re: Camshafts for the EG33.

Quote:
Originally Posted by oab_au View Post
Did they say what the valve timings, or lobe centers, would be.?

Harvey.
Yes, I've got all that info
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  #59  
Old 08-29-2012, 07:55 PM
bazza bazza is offline
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Re: Camshafts for the EG33.

Upon receiving my fancy ground cams back, I was able to see clearly the issue people spoke about but never explained in the numerous cam threads here - and that is when the cam "rides the journal and not the lobe", which made zero sense to me at the time as the actual bearing journals are around 28mm and the regrind takes the cam down to 29-30 mm depending of course.

This shows a section of the camshaft next to the lobe - the bucket is wider than the lobe if you recall. So if you grind the base circle down to much the bucket will ride the cam shaft rather than the lobe at this point which from memory it is cylinder 1 and 2 (intake only). I think this was the issue LAN talked about his thread with the early cam issue. Makes sense? Mine for interest sake is a just clear so it should be fine - if not, nothing 2 mins with the file couldn't solve.

Last edited by bazza; 09-11-2012 at 10:40 PM.
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  #60  
Old 09-11-2012, 10:46 PM
bazza bazza is offline
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Re: Camshafts for the EG33.

Well, a little bit of a hicup - mail damage to cams so had to be sent back to be fixed etc. All solved now so we can proceed. Not a major issue as I spent the time working on other areas of the racecar.

But here they are, nothing really to look at. Getting closer to having it running. For interest sake there has been a huge amount shaved off the base circle but somehow the buckets still contact the cam even without them containing oil - so with oil pressure I expect this to work very nicely. Hydraulics ftw!!!

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