Fastdriver1992

iTrader: (1)

on a 2004 ls1 what is the stock injector size 28lbs?? and how do u know when u need a larger injector? and what size and brand would u recommend for a car making 450bhp

Thanks
Anthony

brian_rs/ss

the next step up is 30 lb svo's. that's what im running at 396 rwhp(466 bhp). but really you don't have to upgrade till 400+ rwhp. i just went ahead and did it because i knew i was close to that mark and the next few mods i do will put me well over 400. also the 2000 f-body's come with 26lb injectors that max out a hair lower. but the next time you go get a tune look at your AFR chart, and ask the tuner what the duty cycle is on your injectors at redline.

TORCHD 02 TA

iTrader: (39)

I did injectors on my car when I changed my cam.. You need to hook your car up a HP tuners and see what Duty Cycle you're running. Like I said when I did the cam, my Duty Cycle was 98%.. That means my injectors were spraying pretty much all the time. 108% is all the way open. I bought FORD 42# injectors, tuned them and now my DC is 54%


all mods are in my sig

Fastdriver1992

iTrader: (1)

the car is 2004 gto wit headers and an slp exhaust

he plans on getting a 228/232 .551 lift 112lsa cam wit ls6 heads and springs so i wanted to know what fuel injectors he would need if he would need any because fuel injectors r very expensive

Thanks
Anthony

p.s what is a duty cycle??

TORCHD 02 TA

iTrader: (39)

I have a 228/232 .588/.595 on a 110 cam.. Duty Cycle is how often your injectors are spraying.. With all the mods in my sig, my injectors were at 98% pretty muched maxed out.. I put in 42# injectors and brought my DC down to 54%

brian_rs/ss

108% is full duty cycle, meaning that the injector should not be pushed past that point or you could go lean etc. but duty cycle is pretty self explanitory...it's how much the injector is working in layman terms.

i was lucky and had a friend that was upgrading from 30 lb to 42 lb and i bought his 30's for reall cheap.

TORCHD 02 TA

iTrader: (39)

LOL you and I said the same thing. I pretty much said what you said in post #3

and I got my Ford 42# injectors for $125 brand spanking new in the box.. Friend needed cash and was desperate to get rid of them