370, Garrett GT55-94, truck manifolds build thread. ***UPDATE 12-10***
#401
http://www.youtube.com/watch?v=rAYpcBDcgyk
Car did good at the track. Went a best of 9.81 @ 138.8 with a 1.50 60ft. 1/8th mile was 6.30 @ 115
Also i switched out my BOV spring to the tightest for the JGS 60mm, know i cant boost any lower than 12 psi even with a 7psi wastegate spring. Someone please explain this to me!
Car did good at the track. Went a best of 9.81 @ 138.8 with a 1.50 60ft. 1/8th mile was 6.30 @ 115
Also i switched out my BOV spring to the tightest for the JGS 60mm, know i cant boost any lower than 12 psi even with a 7psi wastegate spring. Someone please explain this to me!
What front shocks you running btw?
now on the gate, it can only one thing and thats insufficent flow threw the gate. Either wastegate location causing a flow issue or wastegate valve size. If you have a soft spring and its still creeping it must be flow.
#405
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From: Thomasboro, ILL
#406
Nice times for the mph! Did you get a chance to weigh it the track?
I think launch rpm should always be dictated by stall speed, and what the car can put down and hook. If you can launch at 3500rpm and 10 psi of boost and it dead hooks, or at 4500rpm and 10 psi and it dead hooks, you can probably decide for yourself which one is going to make the better short time.
Although I found that if I launch 100-200rpm before the max stall speed of my converter which is 3800ish rpm and let it flash to 4400 when the car starts to move, it gives it a better hit off the line from the sudden rise in rpm off the brake to when it actually starts to move.
I think launch rpm should always be dictated by stall speed, and what the car can put down and hook. If you can launch at 3500rpm and 10 psi of boost and it dead hooks, or at 4500rpm and 10 psi and it dead hooks, you can probably decide for yourself which one is going to make the better short time.
Although I found that if I launch 100-200rpm before the max stall speed of my converter which is 3800ish rpm and let it flash to 4400 when the car starts to move, it gives it a better hit off the line from the sudden rise in rpm off the brake to when it actually starts to move.
#407
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From: Thomasboro, ILL
Nice times for the mph! Did you get a chance to weigh it the track?
I think launch rpm should always be dictated by stall speed, and what the car can put down and hook. If you can launch at 3500rpm and 10 psi of boost and it dead hooks, or at 4500rpm and 10 psi and it dead hooks, you can probably decide for yourself which one is going to make the better short time.
Although I found that if I launch 100-200rpm before the max stall speed of my converter which is 3800ish rpm and let it flash to 4400 when the car starts to move, it gives it a better hit off the line from the sudden rise in rpm off the brake to when it actually starts to move.
I think launch rpm should always be dictated by stall speed, and what the car can put down and hook. If you can launch at 3500rpm and 10 psi of boost and it dead hooks, or at 4500rpm and 10 psi and it dead hooks, you can probably decide for yourself which one is going to make the better short time.
Although I found that if I launch 100-200rpm before the max stall speed of my converter which is 3800ish rpm and let it flash to 4400 when the car starts to move, it gives it a better hit off the line from the sudden rise in rpm off the brake to when it actually starts to move.
#409
Nice race weight too, that car is going to fly once you start running out more rpm through the traps in the 1/4.
What's the rated stall speed on your converter? If it's let's say 4000rpm set your 2 step at 3700-3800 and see how much boot can possibly be built at that rpm.
I'd say if you can get 10psi of boost built at 4000-4500, that's going to be the hot ticket for getting it moving out in the fastest way possible. Hell I know of some other guy's that launch with 15psi or more regularly. Those cars are heavier than yours though, so you may not need as much boost or rpm to get it to 60' where you want it to.
What's the rated stall speed on your converter? If it's let's say 4000rpm set your 2 step at 3700-3800 and see how much boot can possibly be built at that rpm.
I'd say if you can get 10psi of boost built at 4000-4500, that's going to be the hot ticket for getting it moving out in the fastest way possible. Hell I know of some other guy's that launch with 15psi or more regularly. Those cars are heavier than yours though, so you may not need as much boost or rpm to get it to 60' where you want it to.
#410
Wastegate spring pressures are very close to actual, if the gate dumps to atmosphere. You must have about 5 psi of backpressure in the exhaust system at that point.
#413
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From: Thomasboro, ILL
Nice race weight too, that car is going to fly once you start running out more rpm through the traps in the 1/4.
What's the rated stall speed on your converter? If it's let's say 4000rpm set your 2 step at 3700-3800 and see how much boot can possibly be built at that rpm.
I'd say if you can get 10psi of boost built at 4000-4500, that's going to be the hot ticket for getting it moving out in the fastest way possible. Hell I know of some other guy's that launch with 15psi or more regularly. Those cars are heavier than yours though, so you may not need as much boost or rpm to get it to 60' where you want it to.
What's the rated stall speed on your converter? If it's let's say 4000rpm set your 2 step at 3700-3800 and see how much boot can possibly be built at that rpm.
I'd say if you can get 10psi of boost built at 4000-4500, that's going to be the hot ticket for getting it moving out in the fastest way possible. Hell I know of some other guy's that launch with 15psi or more regularly. Those cars are heavier than yours though, so you may not need as much boost or rpm to get it to 60' where you want it to.
So how do i build more boost of that brake? RPM?
#418
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From: Thomasboro, ILL
ALSO raced a new R1 with a good ride that only weighs 130 pounds. Got 3 vids of it. We raced from a 20-40-80mph rolls. The videos are in my youtube profile if you want to see em.
#420
Set it at 4500 then and your going to need more timing to spool the turbo. You can sit there, but most valve body manufacturers don't reccomend you sitting on the brake longer than 3-4 seconds max although people do it longer sometimes.