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Old 08-10-2011, 05:17 PM   #26
Crystal_Imprezav
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Thanks, I will try some 30psi pulls later today. In the meatime, here is some data:

Old 8.5:1 Setup that went [email protected] and would have gone 9's with a [email protected] 1/8th mile on a seperate pass.


New 9.2:1 Setup (Or Manleys "9.8:1" pistons):


Both pulls at 27psi tapering to 24-25psi. Same road, same conditions. While this one is only shows a 40whp difference most of my road dynos from the old setup were more around 650whp but I don't have those logs saved on this computer so I will post those later.
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Old 08-10-2011, 08:02 PM   #27
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Here's the cam card Micah.

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Old 08-10-2011, 08:32 PM   #28
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So MD05STi was partially right...

Here are some tuning notes:

1) Drop the timing 4* and raise the boost 4psi ='s a 40whp loss period.... No Evo tuning strategy working with this setup.
2) Drop timing 1-2* and raise boost 3-4psi. Picked up about 30whp so I am getting closer to where I was.
3) Is it worth ANY of the trouble to switch to higher compression (IMO anything about 8.8-9:1)???? Nope... If you can't tune yourself, be prepared to pay a tuner a lot of money for trial and error on a dyno...
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Old 08-10-2011, 08:40 PM   #29
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Hey jeff I still think you lost power due to cams especially the smaller exh cam.My custom set from kelford has a lrger duration cam for the exh than the intake which I think helps the motor breath a little better.
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Old 08-10-2011, 11:21 PM   #30
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Quote:
Originally Posted by john 1badSTI View Post
Hey jeff I still think you lost power due to cams especially the smaller exh cam.My custom set from kelford has a lrger duration cam for the exh than the intake which I think helps the motor breath a little better.
Then that would mean my Cosworth cams would have exhibited the same behavior... 278/276
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Old 08-11-2011, 01:00 AM   #31
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Made some progress tonight. Still doesn't feel as good as it did before but it is getting there.



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Old 08-11-2011, 01:27 AM   #32
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Quote:
Originally Posted by Crystal_Imprezav View Post
Then that would mean my Cosworth cams would have exhibited the same behavior... 278/276
276 is still better then 268. Would like to know lift of old cosworth cams though.

Have you played with AVCS at all?

I don't think the fact that you blaming your higher compression is valid because you changed your cam setup as well.

Again have you checked the contact of your e85? A change in that can easily affect your potential for power. Not huge but 30-50whp depending on what it is.
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Old 08-11-2011, 01:58 AM   #33
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dominic just brought up this debate a while ago in here.

On my 07 forester we did a quick rebuild with stock sti pistons when it blew #4. those with D25s make it like what 9:1 (MICAH....) on my 20gxt i maxed out the maf at 404whp.
Then i switched to b25 heads ported and polished with bc springs and 272 bc cams and je ots pistons. I maxed out my same maf setup at 385whp and even had to turn it down more since it maxed out on the street. SO im guessing im at like 370 now.

So i made more power on a stock longblock with d25 heads and high compression, than i did with built heads and pistons on low compression.
same exact bolt on setup.
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Old 08-11-2011, 02:18 AM   #34
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Every tank of E85 is checked.


There is no way, the Kelford cam's are choking the setup especially for the amount it has lost. Everyone loves talking trash on Cosworth cam's but now we have people thinking they killing power vs a more aggressive (especially with ramp rate) Kelford cam. If the cam was the problem, I should be having issues with spool as well. It should sway one way or the other and the way it is being VERY picky with boost vs timing does not make sense for a cam problem. If it was a problem with AVCS I should also be having problems with spool. I have tweaked AVCS all over the place. It is not the problem.

At this point I 100% agree with Topspeed. I have seen HC work wonders on the EVO but it has been the complete opposite on the Suby. Like I said, a lot of people will throw their opinions out there. I posted the data... Someone prove me wrong.

So far, I have 2 other people with like setups just switching from stock or 8.5:1 to 9ish:1 that should be up and running shortly. So I guess if no one can validate my data, these two others cars should prove or debunk my theory (*cough* John1BadSTi hurry up lol)
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Old 08-11-2011, 02:37 AM   #35
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Quote:
Originally Posted by Homemade WRX View Post
You also didn't try the same seetup on 'high' compression and then on 8.5:1. You went to a taller lift but narrower duration intake and exhaust cam. Don't you know top end power tends to like a long exhaust duration?

Thats what she said. (o:;
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Old 08-11-2011, 09:46 AM   #36
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Quote:
Originally Posted by Crystal_Imprezav View Post
Here's the cam card Micah.

I'll snag a pic of my old cossie cam card over lunch and post it up.
I'm still saying the narrowed exhaust cam duration and probably some shift in the valve event timing.

Quote:
Originally Posted by john 1badSTI View Post
Hey jeff I still think you lost power due to cams especially the smaller exh cam.My custom set from kelford has a lrger duration cam for the exh than the intake which I think helps the motor breath a little better.
truth...longer exhaust duration helps carry the top end power.

Quote:
Originally Posted by project_skyline View Post
I don't think the fact that you blaming your higher compression is valid because you changed your cam setup as well.
Very valid point that I didn't even think of. If you have more overlap lobe area, you are actually losing static compression ratio, which is why you should really check dynamic compression ratio; take into effect loss from valve openings.

I'd still like to see you slap at least the old exhaust cam into the engine.


Dave, sorry but I don't want to do your CR
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Old 08-11-2011, 11:13 AM   #37
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Well I figured he already calculated that...so yah, let's figure that out. It's gonna be higher surely. What valve springs are u using? If they arent up to the task, that will hinder power too...
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Old 08-11-2011, 11:46 AM   #38
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Old 08-11-2011, 12:43 PM   #39
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Here is my 2 cents FWIW - and that's probably not much.


1) your exhaust duration is less than before. That means there is "potential" for less power on the top end.
2) The cams are totally different either way. That means the overlap is different.
3) You now have LIC adjustable idlers, maybe the cam timing was a hair different before. Even the smallest bit of cam timing can make a large whp difference at your power levels.
4) In theory more compression should lead to a linear power gain across the board. That is unless you run into being knock limited.

Are these the same heads as you had on the previous build?

So if I were to have the exact setup as you and see the differences in the power band. I would just take some timing out, run more boost and rev it less. Maybe try to go to a larger diameter tire for drag racing to help maximize the power band.
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Old 08-11-2011, 03:31 PM   #40
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Quote:
Originally Posted by Crystal_Imprezav View Post
That sheet has an error in duartion values for both 1mm and .5mm lift durations. Values for 1mm lift = 180 + 47 + 3.5 Which = 230.5, not the 236.5 they say. So what is wrong, the values or the math?

If taking their cam values, the exhaust cams are near identical on valve timing events, however the intake cams are VERY different. The first thing I noticed on the Kelford is how late the intake valve is opening and closing.

Are you running the same or near the same AVCS timing? are you going fully retarded on the intake? If so, you could be hindering your charge time and charge volume. Your IVO is now 18* (nearly full half the adjustment range) more retarded than it was prior. Just for instance at 20* retarded on intake, your IVC is 88* ABDC


did you check cam centers at least when you installed the cams?
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Old 08-11-2011, 05:16 PM   #41
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Quote:
Originally Posted by Crystal_Imprezav View Post
Every tank of E85 is checked.


There is no way, the Kelford cam's are choking the setup especially for the amount it has lost. Everyone loves talking trash on Cosworth cam's but now we have people thinking they killing power vs a more aggressive (especially with ramp rate) Kelford cam. If the cam was the problem, I should be having issues with spool as well. It should sway one way or the other and the way it is being VERY picky with boost vs timing does not make sense for a cam problem. If it was a problem with AVCS I should also be having problems with spool. I have tweaked AVCS all over the place. It is not the problem.

At this point I 100% agree with Topspeed. I have seen HC work wonders on the EVO but it has been the complete opposite on the Suby. Like I said, a lot of people will throw their opinions out there. I posted the data... Someone prove me wrong.

So far, I have 2 other people with like setups just switching from stock or 8.5:1 to 9ish:1 that should be up and running shortly. So I guess if no one can validate my data, these two others cars should prove or debunk my theory (*cough* John1BadSTi hurry up lol)
I am trying Jeff but I am at the mercy of cp on the custom 101mm pistons which should be here next week sometime.Just for info the changes I am making fromn the previous setup is ported +1mm d25 heads,1mm lrger bore and 9:1 pistons running a .053 custom sce gskt,everything else will be the same.I will post results when motor is done ,broke in and ready to hit the dyno.
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Old 08-11-2011, 05:48 PM   #42
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Quote:
Originally Posted by Homemade WRX View Post
That sheet has an error in duartion values for both 1mm and .5mm lift durations. Values for 1mm lift = 180 + 47 + 3.5 Which = 230.5, not the 236.5 they say. So what is wrong, the values or the math?

Wow good catch. Are you a human? Hahahaha

so... the .050 spec is off as well.

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Old 08-12-2011, 04:48 AM   #43
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Quote:
Originally Posted by Homemade WRX View Post
That sheet has an error in duartion values for both 1mm and .5mm lift durations. Values for 1mm lift = 180 + 47 + 3.5 Which = 230.5, not the 236.5 they say. So what is wrong, the values or the math?

If taking their cam values, the exhaust cams are near identical on valve timing events, however the intake cams are VERY different. The first thing I noticed on the Kelford is how late the intake valve is opening and closing.

Are you running the same or near the same AVCS timing? are you going fully retarded on the intake? If so, you could be hindering your charge time and charge volume. Your IVO is now 18* (nearly full half the adjustment range) more retarded than it was prior. Just for instance at 20* retarded on intake, your IVC is 88* ABDC


did you check cam centers at least when you installed the cams?
Nice catch on the math error, I wonder the same thing.

Also if you look at the second link they list different openings for the cosworth cams, is that link to new ones or not?

From what I see the cosworth cams are actually pretty decent and maybe the kelfords are what the lose of power came from. But I'm tired, its late and probably not thinking quite clearly.

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Old 08-12-2011, 08:38 AM   #44
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Quote:
Originally Posted by SW00P_G View Post
Wow good catch. Are you a human? Hahahaha

so... the .050 spec is off as well.
Just an anal engineer...I thrive on numbers


Quote:
Originally Posted by project_skyline View Post
Nice catch on the math error, I wonder the same thing.

Also if you look at the second link they list different openings for the cosworth cams, is that link to new ones or not?
I know the second link is from the old cams...as that's the card that I have from back in 07.

Jeff, I know I said to toss some AVCS at the intake cam but didn't mean the full 20* for the full duration. Yes, retarding cam timing up top usually does increase top end power, so that assumption you made is correct.

I'm still suspect of the changes in cam. My only other thought is that these cams really are designed for BIG boost or higher manifold pressure ratios and elevated RPM use. It would explain the massive gap between EVC and IVO. It'll also then work with the later IVC.
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Old 08-17-2011, 08:44 AM   #45
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Crystal_Imprezav, anything new with this?

Dumb question: obviously there are a number of people that have a way better understanding of Cams then I ever will. Why isn’t there a thread/sticky outlining some of the basics? Or is there one and I just missed it?
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Old 08-17-2011, 09:34 AM   #46
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im hoping to have my motor in this weekend, its a ver8 207 with 9.0-9.1:1 compression with stock ver 8 spec C cams and +1mm valves im looking to see what kinda of power it makes, i dont have a before and after though so it will be a little tough to compare, just know i was making 380 on a busted 205 so that will be my more or less baseline
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Old 08-17-2011, 02:26 PM   #47
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Nope, latest hiccup is this HC is causing me to get spark blowout way easier... Just put a fresh set of plugs in but I got some misfires yesterday so... At this point, I am over the whole high-compression hype. I am pretty sure there is a reason no other shops, tuners, etc have chimed in here... I am going to take it easy on this setup until I have time to swap the pistons out back to 8.5:1 Wiseco's.
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Old 08-17-2011, 02:42 PM   #48
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Have you considered upgrading to CDI ignition to fix spark blow out?
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Old 08-17-2011, 02:47 PM   #49
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U crazy!!! I thought U had spark issues on the old setup?

Either way, if you switch back please update with your results.
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Old 08-17-2011, 03:59 PM   #50
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Quote:
Originally Posted by Crystal_Imprezav View Post
Nope, latest hiccup is this HC is causing me to get spark blowout way easier... Just put a fresh set of plugs in but I got some misfires yesterday so... At this point, I am over the whole high-compression hype. I am pretty sure there is a reason no other shops, tuners, etc have chimed in here... I am going to take it easy on this setup until I have time to swap the pistons out back to 8.5:1 Wiseco's.
you'll also notice that no shops cam in and agreed that HC was a waste or that it didn't work
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