So I'm trying to make a few final decisions as far as injector size and pulley size. I'd like to get to about 360-380whp with my 2006 S. The 425hp fuel kit comes with a walbro 255 pump and 650 injectors. It says for up to 425 hp but its referring to crank hp. If I'm trying to run 10-11 psi should I be good with those injectors or will I need to go up in size? For 10-11 psi should I get the 4.0" or the 3.8" pulley? Chart says 10psi for the 4.0" but I know that doesn't always work out exactly. Also, I really just want to run pump gas but should I set it up to run flex fuel? Are most of you guys just running pump gas for 10-11 psi? And finally, is the TIAL BOV worth the extra money or just go with what the kit comes with? As far as tuning I already have a flashpro and will be taking it to Evans.

Thanks

Jon

 

Other wiser people with actual experience will chime in, but for 10-11 psi you do not need flex fuel. With your returnless fuel system the added complexity is definitely not required.

most people go with ID1050x injectors, they will allow for you to maximize your current fuel system and the 255 walbro will provide enough for you at 11 psi. You don’t need a bigger pump. But the 650 injectors are probably a tad too small at anything more than 10 psi from what I’ve seen. You don’t want to be trying to run them at max duty cycle all the time, it leaves little room for error.

just my 2c; I’ve looked into this kit extensively but have no first hand experience FWIW

 

Spec out your fuel system with the expectation that you'll want more power (you will)....Before you know it you're going to want to run a 3" pulley. Buy once, cry once.

 

Ok, I just went back and looked at the stage 2 kit. It comes with the 1050ID injectors and the Walbro 255 pump. For some reason the fuel packages they offer come with the 650cc injectors and Walbro or the 1050 injectors and an AEM340 pump. I'll get the 1050IDs with the Walbro 255. These do fit on the factory fuel rail. Right?

 

Yup!

Also, they should be offering you the latest Walbro fuel pump, the GSS352, which is now a 350lph pump vs the 255lph GSS342, but it shares the exact same body. If not, I'd just go ahead and get the Walbro elsewhere. As far as I know the GSS342 255lph Walbro is no longer being made.

 

While the ID1050 is larger than you need, its easier for tuner to work with. Worth it just for that, never mind its capacity and upgrade path future proofing.

 

Thanks for all the feedback. I will definitely get the ID 1050s and make sure I get the updated GSS352 pump. So you think the 3.8" pulley or 11psi will get me around 380whp? I really don't want to overshoot much either and end up over 400 because I really don't want to break stuff..lol. I'd feel better at 375 than like 415. I know the numbers are arbitrary but I want to keep a balance.

 

Ultimately whp and dyno readings are just a number, and will vary wildly between dynos. I doubt you'd feel a drastic difference between 375 and 415 anyway. The bottom line is the car will be fun to drive once you get done getting everything together and spending all the money, lol. I don't think you'll have a problem even maxing out the power potential of the kit with a 3" pulley in terms of reliability. From everything I've read and from various testimonials from supercharged guys they always seem to end up wanting more, and to that end I decided to full-send my own setup right out of the box. I'm going to be running a TTS kit with a -92 blower, smallest pulley, & flex fuel. There may be a bit more potential down the road with cams & intake manifold perhaps, but that's gonna be it. Only option after that is to go turbo, which isn't happening for me. I figured I'd just spend the money once and have everything required to maximize the output of the setup. Thank @RAIN H8R for that one...He's a bad influence on me.

 

I'm not a bad influence, I just need someone to share my experiences with, and its nice to find a sucker every once in a while that does what I suggest!

 

I have a walbro 255 high pressure plus ID1050x injectors on my IMT S/C car that's a 2006 and have alot of room left in my system and I'm at 350whp at 8psi and 60ish% duty cycle. So while you can look for bigger fuel pumps (if you do I'd likely upgrade your fuel pump wiring) and I'd get the SoS fuel pressure regulator as it gives you a few extra psi.