fp red dyno is a bit lazy ( suggestions)
May 24, 2017, 10:40 AM
#17
I would guess that the exhaust runners are too large on your custom exhaust manifold. Try switching to a ported stock exhaust manifold because this will guarantee to improve spool up time. You could also pair the turbo with the FP exhaust manifold if you want a more aggressive option.
Also, post up a picture of the custom exhaust manifold just to verify how it's designed.
A stiffer wastegate would also help but you should be fine with the one you have now.
Also, post up a picture of the custom exhaust manifold just to verify how it's designed.
A stiffer wastegate would also help but you should be fine with the one you have now.
May 24, 2017, 10:48 AM
#19
Pushing the boost leak test up to 28 psi will probably blow a vacuum line on the back of the intake manifold rather than find an obvious leak.
May 24, 2017, 11:59 AM
#21
Have you experienced compressor surge or boost creep with this setup?
I would try swapping in a stock ported exhaust manifold to see if that changes anything. If it doesn't then switch from an internal wastegate to external wastegate on your custom manifold.
I would try swapping in a stock ported exhaust manifold to see if that changes anything. If it doesn't then switch from an internal wastegate to external wastegate on your custom manifold.
May 25, 2017, 10:18 AM
#23
I have never seen that happen during a boost leak test. Any leaks that happen below 20 psi are usually found in the same places. Any leaks above 20 psi are usually behind the intake manifold coming from the vacuum lines for the EGR and related accessories.
Pushing the boost leak test up to 28 psi will probably blow a vacuum line on the back of the intake manifold rather than find an obvious leak.
Pushing the boost leak test up to 28 psi will probably blow a vacuum line on the back of the intake manifold rather than find an obvious leak.
Well it sounds like you have a problem then. Isnt this the reason why you do a BLT? Who even runs an egr anymore? Also, your logic is flawed in thinking where leaks happen. They can happen anywhere at any given psi if the system isnt up to par.
May 25, 2017, 11:04 AM
#24
EvoM Guru
iTrader: (1)
Every single system I've tested, if it was good at 25psi, it was good at 40+ psi. Only places I usually see leaks are vacuum lines and TB shaft seals.
May 25, 2017, 11:37 AM
#25
As I stated, all systems are different. Ive seen leaks everywhere to be honest and all at ranging psi readings. (Ive worked on a lot of cars) intercooler pipes, bov's, vacuum lines, etc. Heck, Ive even seen pre turbo leaks, internal turbo leaks, the list could go on. If air flows through it, chances are Ive seen a leak there at some point in my life.
Long story short, never go off the word "typically" or "usually" when testing anything. Their setup is not your setup. My 2 cents.
Long story short, never go off the word "typically" or "usually" when testing anything. Their setup is not your setup. My 2 cents.
May 25, 2017, 05:55 PM
#26
Account Disabled
If it's a home built exhaust manifold, it'll be leaking at one of the exhaust flanges.
You've also got to measure the preload on the WG and increase it by adjustment.
You've also got to measure the preload on the WG and increase it by adjustment.
May 27, 2017, 02:17 AM
#30
Here is what I would check.
Boost leak test while moving the throttle blade.
Turbo and housing
Tighten the actuator for some preload but don't go overboard or boost control can become harder to manage. The guys that go overboard aren't doing themselves any favors unless it's drag.
You could also try another actuator with a 20-22psi spring. 25 may be too much for pump gas or have worse boost control. You also don't want a big spike below 4000 in high gears on the stock block. In my experience an 18psi forge actuator was good for about 29-30psi until 7500-8000 with light preload. A 25psi FP actuator was good for 600whp + and 32-33 @8000. This turbo tapers as backpressure increases but should still make power at 30-33 up top of needed. You can make 40 at lower rpm if you want to swing for the fences.
If it's still lazy and falls out the top I would put an FP manifold on it . It's better then the stock design and may scavenge better then what you have. I wouldn't bother with a stock snake ported unit unless that's all you have.
The manifold seems to be the biggest variable. I've got a 9 and even on my stock engine I could make over 400ft lbs @3800-4000 if I wanted to with an unported manifold and FP BB. Your 8 and JB shouldn't be that far behind on a small turbo.
Don't get too caught up in porting it or stuff. 99% of the time it's better to keep things simple.
Boost leak test while moving the throttle blade.
Turbo and housing
Tighten the actuator for some preload but don't go overboard or boost control can become harder to manage. The guys that go overboard aren't doing themselves any favors unless it's drag.
You could also try another actuator with a 20-22psi spring. 25 may be too much for pump gas or have worse boost control. You also don't want a big spike below 4000 in high gears on the stock block. In my experience an 18psi forge actuator was good for about 29-30psi until 7500-8000 with light preload. A 25psi FP actuator was good for 600whp + and 32-33 @8000. This turbo tapers as backpressure increases but should still make power at 30-33 up top of needed. You can make 40 at lower rpm if you want to swing for the fences.
If it's still lazy and falls out the top I would put an FP manifold on it . It's better then the stock design and may scavenge better then what you have. I wouldn't bother with a stock snake ported unit unless that's all you have.
The manifold seems to be the biggest variable. I've got a 9 and even on my stock engine I could make over 400ft lbs @3800-4000 if I wanted to with an unported manifold and FP BB. Your 8 and JB shouldn't be that far behind on a small turbo.
Don't get too caught up in porting it or stuff. 99% of the time it's better to keep things simple.
Last edited by Abacus; May 27, 2017 at 02:29 AM.