I'm running a GT28RS MAM Sleeper kit with an FMIC and a Tial 38mm wastegate. I'm hitting about 6-7psi on the boost gauge. What's weird is that I thought I was running just over 6psi of boost, but lately I've been reading right at the 7psi mark on the gauge. The wastegate is 10 years old with a 10 year old spring, so maybe the spring is getting a bit stiff or there is crud inside and it needs a cleaning.
Also my HKS BOV is 10 years old. I wonder if it's leaking.
Anyways, the car is running great, from the seat. AFRs are about low to mid 11's most of the time, sometimes in certain gears they go to 12.5 and there are some spots where I occasionally see it lean out to high 12's or very low 13s (but not for long and I try not to stay in that). It's not always consistent. I suppose that's the downside of the FMU.
The goal is to have a daily-driven turbo car. Reliability is key. I will autocross the car a few times in the summer and I'd like to be able to autoX it without blowing my engine.
So given that the car has a 10-year old fuel pump and I'm running closer to the limits of acceptable FMU/RRFPR usage and that I'm not seeing the most consistent of AFRs, I am getting somewhat nervous that this setup will backfire on me at some point.
So, I was thinking that to be truly safe and reliable, I should be running SSAFC to keep the AFRs in rock solid high 11's and never enter above 12. Running an electronic boost controller might be nice to help increase turbo response time (avoid wastegate partially opening at midboost levels until target boost is reached). Also, I can reinstall the factory fuel rail and remove the big mess of fuel cables routed in the engine bay.
My questions are:
1) Is SSAFC a good choice for daily-driven 7psi use? Stock engine, 163K miles.
2) Am I pissing away money and should I just keep my FMU setup as is for the foreseeable future? (maybe replace the fuel pump w/ a fresh one?)
3) If I keep the FMU, is adding EBC for rock-solid boost control enough to keep things predictable?
4) Is there a good/simple electronic boost controller that I could add to the SSAFC setup?
5) What are reasonable daily driven psi limits on a GT28RS? The car feels f'king fast right now. I don't think I need more psi. But I do wonder, how much higher could I go safely?
Also my HKS BOV is 10 years old. I wonder if it's leaking.
Anyways, the car is running great, from the seat. AFRs are about low to mid 11's most of the time, sometimes in certain gears they go to 12.5 and there are some spots where I occasionally see it lean out to high 12's or very low 13s (but not for long and I try not to stay in that). It's not always consistent. I suppose that's the downside of the FMU.
The goal is to have a daily-driven turbo car. Reliability is key. I will autocross the car a few times in the summer and I'd like to be able to autoX it without blowing my engine.
So given that the car has a 10-year old fuel pump and I'm running closer to the limits of acceptable FMU/RRFPR usage and that I'm not seeing the most consistent of AFRs, I am getting somewhat nervous that this setup will backfire on me at some point.
So, I was thinking that to be truly safe and reliable, I should be running SSAFC to keep the AFRs in rock solid high 11's and never enter above 12. Running an electronic boost controller might be nice to help increase turbo response time (avoid wastegate partially opening at midboost levels until target boost is reached). Also, I can reinstall the factory fuel rail and remove the big mess of fuel cables routed in the engine bay.
My questions are:
1) Is SSAFC a good choice for daily-driven 7psi use? Stock engine, 163K miles.
2) Am I pissing away money and should I just keep my FMU setup as is for the foreseeable future? (maybe replace the fuel pump w/ a fresh one?)
3) If I keep the FMU, is adding EBC for rock-solid boost control enough to keep things predictable?
4) Is there a good/simple electronic boost controller that I could add to the SSAFC setup?
5) What are reasonable daily driven psi limits on a GT28RS? The car feels f'king fast right now. I don't think I need more psi. But I do wonder, how much higher could I go safely?
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