70mm Launch Pressure

[karolko]

This is a slightly vaigue question becasue i knowboost launch pressure depends on track conditions and suspension setup, but i was wondering if some of you guys with a 70mm on a 231" motor and a turbo 400 are launching at. What stall converter are you using with that launch setup as well.

Just trying to get a grip on what is right without having to spend too much time playing around.

Thanks guys,

Adrian

 

[Super6]

my setup was close to yours..i liked 10lbs off the brake...got a few 1.38-39 60fts but i had suspension problems..mainly busted poly bushings in the rear control arms..i have TRZ heim joint control arms now but i am changing over to a v8.........Bob

 

[karolko]

couple of questions for you,

when you launched at 10psi did the turbo spool very quickly or was is still sluggish for a while? I am sure people know where the hump is on this turbo.

Some other quick questions, your 10.15 time: how much boost? How much do you weigh? do you have an XFI?

Thanks alot

Looking for more opinions so keep them coming

 

[Super6]

couple of questions for you,

when you launched at 10psi did the turbo spool very quickly or was is still sluggish for a while? I am sure people know where the hump is on this turbo.

Some other quick questions, your 10.15 time: how much boost? How much do you weigh? do you have an XFI?

Thanks alot

Looking for more opinions so keep them coming

with the PTC torque converter the turbo spools instantly off the trans brake or off the foot brake..the car would be very close in times with or without the trans brake..i was running around 30psi with a hurt #3 piston when i ran the 10.15 with a bad 1.49 60ft..the car weighed 3470 with me in it and i was running a ME-R with the wide band correction..i did drive it some on the street..drives like a stocker till you put your foot in it......it put 570hp at the wheel on 27psi.....hth..Bob

 

[jasjamz]

with the PTC torque converter the turbo spools instantly off the trans brake or off the foot brake..the car would be very close in times with or without the trans brake..i was running around 30psi with a hurt #3 piston when i ran the 10.15 with a bad 1.49 60ft..the car weighed 3470 with me in it and i was running a ME-R with the wide band correction..i did drive it some on the street..drives like a stocker till you put your foot in it......it put 570hp at the wheel on 27psi.....hth..Bob

Was this a stroker? What was the compression ratio? Did you figure out what caused it to hurt number 3 cylinder?

 

[Super6]

ha

no stroker..just a 70k mile bone stock short block...i hurt the piston because i leaned it out...put a double pumper in and a low mile piston that a buddy gave me and beat it some more..i put the piston in the motor with it still in the car and even used the same rings..motor has never been out of the car and i done a leak down test on it before i pulled the heads and intake..2% leakage on all cylinders..i was impressed..i was running .040 cometics so it has a little more compression than stock..the only reason i pulled it down is because i sold the heads and intake and i am going to a v8..hth.....Bob

 

[karolko]

Super6, Would you say that around 10psi is that "Hump" for the turbo?

I have only had threee passes on the turbo, but i only launched at 1psi and it seems like it takes forever to get the boost really going.

Adrian