Injector Sizing Options

[turbohcar]

Alright boys. Here's my debacle now. I just picked up a Supra sidemount with 2.5in inlet/outlets. I've got 2.25in upper and lower intercooler pipes, a GM MAFT for a blow-through setup, and stock 14b @16psi. I'm wanting to purchase a Walbro 255lph pump, Aeromotive FPR, injectors and the necessary fittings to make it all work and rewire the fuel pump at the same time. What I need help with is the correct injector size. I did some playing with RC Engineering's FAQ page and came up with something in the 650-680 cc range. Does that sound right? I want to have plenty of room for adjustment without pushing the injectors too hard. Right now I'm already at my limit with the stock MAS, the stock injectors are maxed out, and I desperately need an Eprom computer to eliminate fuel cut. So, post up your thoughts and concerns please and let me know what you think.

What I need:
Eprom computer
Aeromotive FPR
Injectors
Walbro 255 pump

What I've got to put on:
GM MAFT with translator
2.25 intercooler piping upper and lower
Supra Sidemount

It may not be until Spring when I finally get all of this together and put on but, I atleast want to know what to work for. On a side note, my eventual plans for the car are to go to a fully forged bottom end, cams, and a .50 trim turbo (or maybe something bigger with ball bearings). Right now, I only have enough non-fuel modifications to run 25 lbs of boost and under 400 hp. So, everything's going to change before I go for the really big setup anyway but I thought it might be important to know anyway. I was thinking of going with an EVO III 16G or a 20G turbo after the fuel modifications are done though for an "in between" turbo. Thanks guys

[natedogg]

Well, all the 16G/550cc injector threads I've ever read, they're usually maxing the injectors out or they're really close to it.  So, if possible, I'd like to go with a little bigger injector and have plenty of room for adjustment.

This is true. 550's are only about a 15% increase in flow capability over the 450's. That doesn't give much head room for tuning. Especially on an Evo3 16g which is capable of outflowing the 16g's of old by quite a bit.

I think you're on the right track, Brett. Always best to be a bit conservative and play it safe when it comes to tuning and fuel management.

Right now, all I use to tune the injectors is the MAFT. I plan on going with a DSMlink soon though.