05-29-2014, 01:09 PM | #1 |
Drives: 2012 SS Join Date: Sep 2012
Location: Deale, MD
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Expected boost drop going to 2" LT
I had installed shorty header and high flow cats back before any plans of super charging. After installing my v-3 with a 3.33 pully I knew it was only a matter of time before the cats went just curious about how much boost I'd expect to drop? I was right at 10 at 6500
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05-29-2014, 01:30 PM | #2 |
Drives: Silver 2010 SS Camaro Join Date: Jul 2009
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I would say maybe 1psi
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05-29-2014, 05:44 PM | #3 |
Drives: 2012 SS Join Date: Sep 2012
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Thanks
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05-30-2014, 08:36 AM | #4 |
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had exact set up...I'd bet if you are seeing 10psi with cats on a 3.33 you have an intake restriction. So, put the 2" headers on and drop 1-2, but put an ECS filter on the head unit and pick up just about that. Should keep you around 10psi. ECS or FSP can sell you the filter.
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05-31-2014, 05:47 PM | #5 |
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don't do 2" headers with 10psi! stick with the 1 7/8
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1150bhp Whipple 4.0 Supercharged 427ci Camaro ZL1 |
05-31-2014, 06:32 PM | #6 |
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^ explain why
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05-31-2014, 08:29 PM | #7 |
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because at this power level a 1 7/8 primary is not at all a restriction, you would want to increase the pipe diameter until the primaries are not a restriction, yet stay as small as possible to keep exhaust gas velocity as high as possible and as a result make the most average power.
The ballpark to when you should move to 2" is about 800rwhp
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1150bhp Whipple 4.0 Supercharged 427ci Camaro ZL1 |
05-31-2014, 08:36 PM | #8 |
Drives: 2012 SS Join Date: Sep 2012
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Yep cars going from dd to track only over the next year just figured I'd go for the 2" now
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05-31-2014, 08:50 PM | #9 |
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05-31-2014, 10:20 PM | #10 | |
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Quote:
I saw people gain hp switching from 1 7/8 to 1 3/4 on LS7's go figure. http://ls1tech.com/forums/generation...xperience.html This is a SMALL example, do a search and you will find the answers you're looking for
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1150bhp Whipple 4.0 Supercharged 427ci Camaro ZL1 |
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05-31-2014, 10:53 PM | #11 |
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1 7/8ths is plenty. At 650whp FI kooks 1 7/8ths headers only gained me 5%. No cats in either comparison.
Doing a heads cam build on my ls6 now targeting 450-470 whp (if it was an ls3 this combo would yield about 50-60whp more), keeping the 1.75 longtubes I have now for this.
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06-01-2014, 07:36 AM | #12 | |
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Quote:
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06-01-2014, 08:50 AM | #13 |
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I had 1 7/8" but recommend 2" for any FI now. No reason to upgrade later and I haven't seen any power/torque loss on a good set of them.
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Nick
Corvette Z06 -1200ish rwhp |
06-01-2014, 09:43 AM | #14 |
Svt lol
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I don't know what happened with mine but have a Procharger making 6-6.5 psi and 480 rwhp (no special tune, all stock other than cat back). After installing headers (no tune) I lost 3-3.5 psi and no one knows why I lost so much it wasn't common.
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