STS Fuel Injector Size
Thread Starter
14 Second Truck Club
Joined: Dec 2003
Posts: 1,188
Likes: 0
From: Houma, Louisiana
STS Fuel Injector Size Alright here's the deal. I got my pcm in friday and went log a few runs. Result at wot i'm running real lean, O2s 850 range and getting 5-6* kr. Needless to say i didn't get to race at Southern Shootout. Allen told me i'm maxing out the injectors. What brand and size injector are you STS guys running? Who's got the best price on them? Allen recomended 36# injectors. I'm not planning on running more than 5lbs. boost. But if i did run more boost it wouldn't be more than 8- 10lbs. Thanks in advance.
Could be maxed out injectors. You'd need to log pulsewidths to be sure.
Could be fuel delivery problems. (i.e. fuel pump) You'd need to check fuel pressure under load to be sure.
Might be a tuning issue? (PE set too low, since the pcm can't account for boost.)
You could probably upgrade to 30's, which are 20% bigger than 28.8's (which are really 24's at the same psi everyone else measures at). Or anywhere between 30 and 42. Prices are about the same in that range. Whatever your tuner is comfortable with setting up.
I went with 60's on my setup, but that was based on a 600-650rwhp target. Far as I know, that's the biggest that will idle ok (very short pulsewidths at idle) and that will still run on the stock pcm (high impedance) without a converter box.
Do you know what hp level you're shooting for? That's the most typical way to calculate back to an injector size.
Could be fuel delivery problems. (i.e. fuel pump) You'd need to check fuel pressure under load to be sure.
Might be a tuning issue? (PE set too low, since the pcm can't account for boost.)
You could probably upgrade to 30's, which are 20% bigger than 28.8's (which are really 24's at the same psi everyone else measures at). Or anywhere between 30 and 42. Prices are about the same in that range. Whatever your tuner is comfortable with setting up.
I went with 60's on my setup, but that was based on a 600-650rwhp target. Far as I know, that's the biggest that will idle ok (very short pulsewidths at idle) and that will still run on the stock pcm (high impedance) without a converter box.
Do you know what hp level you're shooting for? That's the most typical way to calculate back to an injector size.
TECH Addict
Joined: Nov 2001
Posts: 2,659
Likes: 1
From: Bellevue, Wa
get 42's and be done with it if you don't EVER plan on going above 500rwhp. If you plan on going higher, go even bigger.
no need to get just barely what you need and be stuck again.
now for a shameless plug
I will sell you my 42's for a good price as I am moving to 60's
PM me if interested.
no need to get just barely what you need and be stuck again.
now for a shameless plug
I will sell you my 42's for a good price as I am moving to 60'sPM me if interested.
