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Old 10-20-2005, 01:06 AM   #41
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Yes, thank you for that info. I'm glad to have your experience on my side!

We don't plan on going too extreme with the compression. I think 10:1 is a nice target, but as I mentioned previously we have NO idea of the stock piston-to-valve clearance. Foghorn, do you have any access to this specification? I posted a thread yesterday on 3800Pro, but as yet I've gotten no reply. I saw a figure in a '95 FSM that listed 'piston clearance' at 39mm 'from the top of the piston.' Does this mean from the top of the piston to the top of the combustion chamber? Also, the '95 L36 was listed at 9.0:1 compression as opposed to 9.5:1... did something change from '95 to '97?

If somebody could answer this question or at least direct me to a person who might know, I would really appreciate it!
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Old 10-20-2005, 04:13 PM   #42
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Foghorn, I'm with ya on possibly having to mill the LIM.
But someone has run 0.030" milled heads and 0.011" samller head gaskets. So you should be able to mill 0.040 off the heads with stock size gaskets.
As far as the compression, doing some quick math using zzp'* article:
And I'm 99% sure that we start at 9.4:1.
(Reducing material 0.111" = 2.2 points in compression)
Milling (and using stock gaskets)
0.030 = 9.99:1 compression
0.040 = 10.19:1 compression
0.050 = 10.39:1 compression
0.060 = 10.59:1 compression
0.070 = 10.79:1 compression
Also I don't really think clearance is an issue. The only thing that really matters is drastically changing the duration. If the duration is too long, the piston will come up before the valve does. But since your going to have a mild cam, the duration shouldn't be off enough to cause clearance issues. Another advantage to having a milder cam is that less material will have to be grinded off the cam and you won't be forced to have a crazy compression ratio.
I mean, maybe when you find out how much you have to mill, and if it'* over 0.040", e-mail zzp and ask if clearance will be an issue while using the zzp GT1 cam since your probably shooting for a cam with less lift/duration.
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Old 10-20-2005, 06:32 PM   #43
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That'* an interesting viewpoint, and might make a difference in our gameplan. Doug'* idea was to keep approximately the same lift but have the cam ground for more duration. These are the kind of things that I need to check before we dive into this process. Maybe I should try to get in touch with Zooomer personally? I'm getting nothing from 3800Pro so far.
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Old 10-20-2005, 11:59 PM   #44
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In terms of lift, I would at least mimic the ER rocker ratio. I believe it'* 1.8 on the intake and 1.85 on the exhaust. That has been found to be the best L36 rocker ratio.
If this (http://engine.firebirdv6.com/cam.html) database is right,
The stock cam lift is .258 intake/.255 exhaust, to mimic the ER ratio lift your cam would need .290 intake/.295 exhaust lift on your cam. And if the duration is 182 intake/190 exhaust, you'll want your duration to be between that and 210/210(GT1 cam). And the higher from stock you go, the higher your powerband will shift.
And as far as contacting zoomer directly, I'd say definitely do it. Maybe after MGM though. He'* answered alot of my questions.
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Old 10-21-2005, 01:13 AM   #45
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Great info... thank you, as always.

Who did the research on the ER rockers to know they're best? Also, it seems you highly recommend the ZZP GT1, but is there any reason why you favor that cam over others? How does it compare to other cams, such as the INTENSE Stage 1 or 1X? Is one necessarily better than another?
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Old 10-21-2005, 12:19 PM   #46
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http://www.easyperformance.com/ (Tech Info/ER Rocker Arms) Did the testing for the rocker arms a little while back. But like I said I believe the ratio is 1.8/1.85. Thats what someone said on cgp..
As far as the my preferance to the GT1 cam goes, A gp ran 14.2 w/ an HVII/TOGs/HVTB/Springs and NO trans work a while back. Another dropped .4 to .6 tenths when they switched from a s1 cam to a GT1. And there are other gp'* running mid 14s w/out headers or trans work too. And just incase you decide to go all out, you can still make 233+ whp with it. So I just see it as a good mild cam that has been proven and you can still take far if you want.
*Remeber the gp'* are lighter and have a 3.29 FDR so I'm not saying a bonnie will run those times.
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Old 10-21-2005, 12:47 PM   #47
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Quote:
Originally Posted by 95naSTA
*Remeber the gp'* are lighter and have a 3.29 FDR so I'm not saying a bonnie will run those times.
Yeah, I wouldn't expect mid 14s from this car !!! However I appreciate the info. I'm hoping to get this thing into stock Series 2 L67 territory when the project is complete (better would be nice!). I think it can be done with the mods I'm talking about, and final cost shouldn't be too high. Hopefully we'll develop a mod plan that can get SE and SLE models into SSEi territory for $500-$600.

As far as piston-to-valve clearance is concerned, I think contacting Zooomer will be the best course of action. Unless Todd pops his head in here and can help me out, ZZP may be my info source for this project. It seems that they've done a little more NA work, anyway.
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Old 10-21-2005, 11:51 PM   #48
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soooo... can we start now?
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Old 10-22-2005, 09:12 AM   #49
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Dear Mr. Sajak,

Please remove the ants from your pants.

Sincerely,

Ben Eichelberger

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Old 10-23-2005, 02:18 AM   #50
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i'm a man of action and few words. Lets get that baby put togeher!
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