Does anyone have any tips for 9 psi jrsc setups, ive already ordered a walbro 255l feul pump, and cant decied on what size injectors or feul pressure to run. Any tuning tips would be helpfull, like timing, water injection? it is on a b16a. thanks

 

Mine's a b18c, so take my advice with some salt:

10psi boost via CRV pulley
320cc Venom Injectors
AEM Fuel Rail FPR (to allow lower FP's)
Cartech 20005i rising rate FPR
Walbro GSS342 pump

Idle FP = 25psi
Static FP on AEM = 40psi
Static FP on Cartech = 35psi
Max FP = 67psi

I have stock timing (16 degrees) and keep my JR BTC set at .6 degrees retard per psi boost. This keeps everything mostly happy with 94 octane gas.

With boosted octane, I can drag race with the BTC at 0.

I do get some part-throttle boosting detonation, but have tuned most of that out with a VAFC richening the 3000-4500rpm range 3-5%. I also am leaning out 17% at all rpms above 5500.

 

I thought the fuel pressure on the FMU should be greater then the fuel pressure at the AEM FPR?

I give props to you man! You have a nice fast car without a hondata. Is vacuum to boost transition giving you any problems? WHen I was using the FMU setup with VAFC on my 00SI at 6lb it was running strong but I hate the vacuum to boost transition. I try the VAFC hack method and the transition was seemless but I hate the surging RPM and it feels like my car is not as strong as before. I'm going the hondata route. Hope no other problems come up.

 

My car has some bumpy spots a standalone would surely fix, but vacuum to boost is not one of them. Smooth transition. Plus, I can cruise like an idiot at 1/2 throttle, 1/2 boost (6psi) and not get any detonation. I doubt it could be any smoother without a standalone.

I have the AEM FPR at a higher static FP than the cartech FPR because I wanted to richen up the vacuum to boost transition zone without increasing max FP. It took me many, many hours of tuning to get the cartech set right and it's the last piece under my hood that I'd want to mess with again!

 

Is that because the cartech doesn't want to adjust FP when you turn the allen key and gets kinda sticky, do you have to keep playing with the vacuum hose (put it on and off again and again) until the fuel pressure starts to go up or down? Mine does that too. I have to keep pulling on and off the vacuum line to kinda give it a bump after I adjust the FP to see the difference on the gauge.

If that wasn't the problem with the cartech, what was? I'd like to know since I have one.

 

Do i need to go out and buy a cartech fpr, or do you think id be fine just getting some 320cc injectors, walbro pump, aem fpr, and using the fpr that came with the supercharger.

 

With 320cc injectors, you'll need a rise rate near 3:1.

The JR FPR (5:1) will make your mix so rich it will suck.

 

My cartech is not sticky except coming back below static after boosting. After boosting, FP might stick at 30psi for 20 seconds or so before going back to 25psi.

My problem was with the response time / bleeding capacity of the cartech. At 10psi boost (12psi in manifold), without a vacuum restrictor in the vacuum line it could not bleed off enough boost to lower the rise rate enough (i.e. FP too high with restrictor). Plus, the restrictor slowed down the response time enough that mashing the throttle would result in a .5 second bog (the mix went uncombustably lean) followed by a brutal slam of power that literally knocked the stereo out of the dash once the Cartech caught up.

The first part of the cure was replacing the tiny checkvalve that came with it that goes outboard of the bleeder valve. I bought the biggest acquarium check valve I could find and bored it out for even more capacity. This let the Cartech bleed off almost enough boost for my setup.

I still needed some vacuum restriction, but as little as possible so as not to slow down the reaction time. I took the stock restrictor out and put a hose clamp around the outside of the vacuum line. Voila! An adjustable restrictor.

Add in many hours of testing and tuning on the highway, and I had the whole mess adjusted so that the restrictor was as open as possible and I still got max FP to where I wanted it and no bogging.