How much boost?

[agwj257]

I will be adding a Star stage II kit very soon, I'm curious about how much boost is good to start with? I have the Howell bottom end kit with 8.6 JE pistons, ported cylinder head, and ofcourse full exhaust system with hi-flow cat. I'll also be adding Crane #0014 turbo cams, oversized valves, Crane valve springs, and AEM cam gears at the same time as turbo. I know alot of people start at like 5lbs but, that's why I built the bottom end first so I could run more. I will be having it professionally installed and tuned. Like I said I'm just curious about it right now.

Thanks for any help.

 

[SilverEclipseT]

wouldn't go higher then 8psi till you do something about the injectors. Unless the star II comes with them, but i dont think they do. The injectors is the only restriction that i see you have.

 

[fwdturbobov1996]

no joke .. you have done everything to run 15 psi and you didnt do the fuel system .. get some * around * 400cc injectors and a 255 fuel pump , which i think you will also have to buy a fpr .

 

[Blueheat23]

I would say get at least 450cc injectors with a Wally 190. There is no reason to use the 255 right now, you wouldn't be putting down enough power. Plus the 255 is really freggin noisy. Definately need a fuel controller to go along with all of that good stuff if you plan on using the stock ECU. A rising rate AFPR would be a great investment as well.

 

[EclipseGS4651]

Hey whats up, I am looking into a engine rebuild with hopefully a turbo in the future. I was looking on howell's site but am kind of lost...do you think you could post some links to the bottom end kit with pistons and the cylinder head? Any info would be great...I am a noob when it comes to turboing the 420A. Thanks, Erik

 

[HadesOmega]

yeah you can go as high as long as you tune it properly. You'll probably start breaking other things though like axles and stuff. But you want to make sure you get all the fuel components you need, fuel tuning is very important the higher in boost you go.

get some bigger injectors, a SFMU, and a safc to fine tune your fuel curve, then take it to a dyno and tune that bad boy.

 

[agwj257]

Sorry to get back so late. I've been busy plus my computer got some kind of virus. O.K. so I need at least 400cc injectors and at least a walbro 190 fuel pump. What about the fuel pump that comes with the Star stage 2 kit? Anyone know its fuel rating? The stage 2 also comes with a FPR can't I just add a S-AFC controller to that to control the fuel flow? Someone let me know if I'm wrong. I'm not sure.


EclipseGS4651- Let me know if you still need those links.

Thanks everyone for your help.

 

[HadesOmega]

ok the star kit doesn't come with a Fuel Pressure Regulator it comes with a fuel pressure riser or fuel management unit. Its job is to increase the fuel pressure for every lb of boost that way you can squeeze more juice out of your injectors so you don't go lean during boost. The problem with this is that the higher you boost the pressure will get higher and higher and I heard running too high a fuel pressure is bad. Now a SFMU is different its like a FPR and FMU rolled into one package. You can adjust you static fuel pressure which will allow you to not idle rich and allow you to tune for bigger injectors. Then you use the SAFC to fine tune your fuel trims. You can't tune with just the safc because if you lean with the safc it will increase your timing also and well boom...