14 lb intercooled procharger
 

what size fuel injector should I run with a 306 X303 TF heads, blown engine. I know non intercooled blown engine needs big injectors(the added fuel helps cool the air charge). But what is the correct size I should run with this combo:confused: :confused:

Injectors...
 

I would guess at least 42# injectors for your combo. Probably bigger.
The more the better, you definitely want to take detonation out of the equation.
Good luck.
Additionally an in-line pump(like a t-rex)to supplement your in-tank 255lph one.

Bigger isn't necessarily always better with fuel injectors. You get them too big and at minimum pressures your engine could run entirely too rich. Yeah, you can run low fuel pressure and the computer will shorten the injector pulse to compensate, but now the injectors won't be running at optimum efficiency. Think of the spray from a garden hose with the house valve only cracked compared to the house valve full open. You still get a decent spray, but at the lower pressure the fuel isn't going to be atomizing as well. Trial and error with a wideband O2 sensor would be the best way to get the correct size. I'm sure everybody's got a wideband laying around, right?';

There's an analyzer on here somewhere that helps you get a good idea what size would be appropriate.

Accel also has some very good flow/pressure data on their site at www.mrgasket.com

SlowGT is right...
 

Perhaps I wasn't specific enough.
There certainly is a optimal injector size to ensure flow and pressure efficiency.
I was basing my 42lb comment on my setup, as I only plan to run 8 lbs of boost. If you are looking for 14 lbs w/intercooler you will definitely need a bigger size.
Also, regarding SlowGT's rich/lean comment: It is important to decide between the FMU route or the custom chip route.
Most tuners feel that a FMU only gets you close and you will always either be a little rich or a little lean.
A custom chip burned exclusively for your hardware combination is the best route and will pay for itself in the long run with reliability.

I've set my sites on an ATI P1SCH @14# intercooled over the winter.

Would the air/fuel ratio adjustment on the rpm extender be good enough? is this just an FMU by another name? I don't know anything about FMUs. but I'd like to get all the info I can instead of waiting til I'm trying to tune it.

Thanks.