Does GT35R + T4 Divided 1.15 A/R = LAG?
I was figuring doing a 6466 in a 1.32 a/r. Since the 6466 in the low to mid 40 psi range basically offers the same power output as the 6766 but with better spool, it should also spool up better than a 6766 with the same turbine housing. Getting a larger hotside should reduce backpressure and help gain some serious top end pull for a high revving build.
A 1.32 would or should spool like a 0.792 single which we already know didnt spool slower than the 0.68 with the efficient compressor wheel and turbine. Jeff's car runs a 1.44 right now and hasnt seemingly lost to the 1.28 while maintaining 48psi of backpressure at 53psi of boost.
I'll grab the dyno sheets to show what I am talking about in a bit.
Aaron
Aaron, how is it actually driving on the street though with the housing change.
Particularly peak boost levels in 1st and 2nd gears from a roll and 3rd gear time to boost from a roll.
I realize for drag racing leaving with launch control it's mostly irrelevant, (until you miss a shift or bog a launch and have to wait for it to respool). But for a street car, it was very noticeable. One local was running the 4202 for some testing with the 1.28 housing on a 2.0L B-series setup and the turbo litterally didn't spool above like 15 psi until third gear if he botched the launch.
Particularly peak boost levels in 1st and 2nd gears from a roll and 3rd gear time to boost from a roll.
I realize for drag racing leaving with launch control it's mostly irrelevant, (until you miss a shift or bog a launch and have to wait for it to respool). But for a street car, it was very noticeable. One local was running the 4202 for some testing with the 1.28 housing on a 2.0L B-series setup and the turbo litterally didn't spool above like 15 psi until third gear if he botched the launch.
Last edited by 03whitegsr; Mar 29, 2013 at 03:56 PM.
Aaron, how is it actually driving on the street though with the housing change.
I realize for drag racing leaving with launch control it's mostly irrelevant, (until you miss a shift or bog a launch and have to wait for it to respool). But for a street car, it was very noticeable. One local was running the 4202 for some testing with the 1.28 housing on a 2.0L B-series setup and the turbo litterally didn't spool above like 15 psi until third gear if he botched the launch.
I realize for drag racing leaving with launch control it's mostly irrelevant, (until you miss a shift or bog a launch and have to wait for it to respool). But for a street car, it was very noticeable. One local was running the 4202 for some testing with the 1.28 housing on a 2.0L B-series setup and the turbo litterally didn't spool above like 15 psi until third gear if he botched the launch.
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1.15 A/R is a sweet spot for top end and spool for an all round setup depending on your goals.
Aaron how restrictive are 1.25" exhaust manifold runners over 700hp with a 1.15 A/R TS T4? I'm hearing the back pressure on 1.25" over 700hp negligible or is 1.5" the go?
Aaron how restrictive are 1.25" exhaust manifold runners over 700hp with a 1.15 A/R TS T4? I'm hearing the back pressure on 1.25" over 700hp negligible or is 1.5" the go?
Last edited by JGNERAEVO9; Apr 27, 2013 at 09:24 PM.
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1.15 A/R is a sweet spot for top end and spool for an all round setup depending on your goals.
Aaron how restrictive are 1.25" exhaust manifold runners over 700hp with a 1.15 A/R TS T4? I'm hearing the back pressure on 1.25" over 700hp negligible or is 1.5" the go?
Aaron how restrictive are 1.25" exhaust manifold runners over 700hp with a 1.15 A/R TS T4? I'm hearing the back pressure on 1.25" over 700hp negligible or is 1.5" the go?
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You could use one of those to measure back pressure and plot that against boost.
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Anyone with any other info for exhaust manifold runner diameter and how it effects back pressure over 700 hp.
You are talking 1-1/2" vs. 1-1/4" pipe, right? Because 1-1/4" schedule 10 pipe has a larger ID then 0.035" wall 1.5"OD tube and Schedule 10 1-1/2" pipe is larger then 0.035" wall 1.75" tube.
Also, schedule 10 will flow about 9% more then schedule 40...
Might seem like a small detail, but if that correlates to power, at 700HP level, you are talking about 60HP difference in potential between the two on flow capability.
Also, schedule 10 will flow about 9% more then schedule 40...
Might seem like a small detail, but if that correlates to power, at 700HP level, you are talking about 60HP difference in potential between the two on flow capability.
Last edited by 03whitegsr; Jul 5, 2013 at 10:25 AM.
Aaron, how is it actually driving on the street though with the housing change.
Particularly peak boost levels in 1st and 2nd gears from a roll and 3rd gear time to boost from a roll.
I realize for drag racing leaving with launch control it's mostly irrelevant, (until you miss a shift or bog a launch and have to wait for it to respool). But for a street car, it was very noticeable. One local was running the 4202 for some testing with the 1.28 housing on a 2.0L B-series setup and the turbo litterally didn't spool above like 15 psi until third gear if he botched the launch.
Particularly peak boost levels in 1st and 2nd gears from a roll and 3rd gear time to boost from a roll.
I realize for drag racing leaving with launch control it's mostly irrelevant, (until you miss a shift or bog a launch and have to wait for it to respool). But for a street car, it was very noticeable. One local was running the 4202 for some testing with the 1.28 housing on a 2.0L B-series setup and the turbo litterally didn't spool above like 15 psi until third gear if he botched the launch.