New Dyno #'s what do you think....
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From: Raleigh, NC
Re: New Dyno #'s what do you think.... Drop 1 to 2 PSI if you have headers
Drop 1 or 2 more if your motor flows more than stock (big cube, heads/cam, etc)
4.10" Pulley - 4.5 to 5 PSI at 6000 RPMs, 6 or 7 at 6500
3.20" Pulley - 10 PSI by 5000 RPMs rising to 12 PSI from 6200 to 6500
Went to Headers/Y-Pipe
3.20" Pulley - 8 PSI by 5000 RPMs rising to 10 PSI from 6200 to 6500
Went to 422 with heads/cam
4.10" Pulley - 3 PSI at 6000 RPMs, 5 at around 6800
3.20" Pulley - 8 PSI at 5000 and greater RPMs
Those are my experiences.
If you only get 4 PSI out of a 3.6 pulley, I would go for the 3.20" to get 7 or 8.... My opinion.
<small>[ February 24, 2003, 05:12 AM: Message edited by: Black LS1 T/A ]</small>
Drop 1 or 2 more if your motor flows more than stock (big cube, heads/cam, etc)
4.10" Pulley - 4.5 to 5 PSI at 6000 RPMs, 6 or 7 at 6500
3.20" Pulley - 10 PSI by 5000 RPMs rising to 12 PSI from 6200 to 6500
Went to Headers/Y-Pipe
3.20" Pulley - 8 PSI by 5000 RPMs rising to 10 PSI from 6200 to 6500
Went to 422 with heads/cam
4.10" Pulley - 3 PSI at 6000 RPMs, 5 at around 6800
3.20" Pulley - 8 PSI at 5000 and greater RPMs
Those are my experiences.
If you only get 4 PSI out of a 3.6 pulley, I would go for the 3.20" to get 7 or 8.... My opinion.
<small>[ February 24, 2003, 05:12 AM: Message edited by: Black LS1 T/A ]</small>
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Joined: Nov 2001
Posts: 3,048
Likes: 12
From: Raleigh, NC
Re: New Dyno #'s what do you think.... Calling one pulley or another an "x" lb pulley is just so bogus to me.
The boost you see will vary by your exhaust, heads/cam, MAF, etc, etc.
Even if one tried to rate them based on a completely stock F-body, the exhaust, cam (is that true for WS6 and SS?) and intake varies on some of them.
Even the ratio gear and whether you are an M6 or an A4 will make the boost you see the longest will vary.
Even then, geo elevation induces further differences one way or the other.
That being said, I only know of two pullies ATI rates for the P-1SC and D-1SC
4.10 = 4.5/5.0 PSI
3.40 = 7/8 PSI.
They may have changed it since I was one of the first few people to buy the new model SC. But, that's all I know they rated then.
One gy told me they sent him out a 4.00" pulley, so I guess things change.
No one can accurately call a specific pulley a certain PSI of boost, in my opinion.
That ALSO being said, stock exhaust, I made 12 PSI with the 3.20" pulley.
It took installing MAC headers/Y-Pipe to drop it 2 PSI down to 10 PSI.
I hope that gives you an idea. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
The boost you see will vary by your exhaust, heads/cam, MAF, etc, etc.
Even if one tried to rate them based on a completely stock F-body, the exhaust, cam (is that true for WS6 and SS?) and intake varies on some of them.
Even the ratio gear and whether you are an M6 or an A4 will make the boost you see the longest will vary.
Even then, geo elevation induces further differences one way or the other.
That being said, I only know of two pullies ATI rates for the P-1SC and D-1SC
4.10 = 4.5/5.0 PSI
3.40 = 7/8 PSI.
They may have changed it since I was one of the first few people to buy the new model SC. But, that's all I know they rated then.
One gy told me they sent him out a 4.00" pulley, so I guess things change.
No one can accurately call a specific pulley a certain PSI of boost, in my opinion.
That ALSO being said, stock exhaust, I made 12 PSI with the 3.20" pulley.
It took installing MAC headers/Y-Pipe to drop it 2 PSI down to 10 PSI.
I hope that gives you an idea. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
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TECH Senior Member
Joined: Nov 2001
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From: Chi-Town, IL
Re: New Dyno #'s what do you think.... Ok, thanks...
Looks like I might have to order two pullies when the time comes, I'm not even sure if I'm going to bother with it now, just might save for the pully I will need on the built motor I plan on doin..
MMS crank pully should stop most belt slippage....(hopefully)...
Looks like I might have to order two pullies when the time comes, I'm not even sure if I'm going to bother with it now, just might save for the pully I will need on the built motor I plan on doin..
MMS crank pully should stop most belt slippage....(hopefully)...
