firechicken76

iTrader: (14)

I got into an argument with a friend the other day, and he told me that the injectors im putting in my car for my supercharger are too small, im installing a magnacharger on an 02 ls1, should be 8-10 psi. I went with 60# injectors. and I was also wondering what the stock injectors can support for N/A power.

got-a-ls1

iTrader: (12)

60# should be pleeenty. im on stock injectors and am probably in the neighborhood of 430-440 rwhp. stock 2000 26lb injectors. lol..

firechicken76

iTrader: (14)

thats what i told him, i told him stock injectors will support upward of 450rwhp, and that my build, i could get away with 42#ers, but went with a little overkill and got the 60#ers. he has a mitsubishi starion, and says his are 750cc.

ucanthangwme

iTrader: (12)

Fuel Injector Size Calculator

http://www.corvetteinjectors.com/calculator.html

ucanthangwme

iTrader: (12)

This one has a cool tool to calculate the horsepower capacity of injectors based on their flow rating:

http://injector.com/injectorselection.php

firechicken76

iTrader: (14)

Ive got another question. why do 4 cylinders require bigger cc injectors than the v8 cars? my friend is making like 300hp in his starion and is using 756cc in.

parks450

iTrader: (17)

Maybe rpm's I wad told why at one point but can't remember why.

zipster

iTrader: (5)

He has only 4 cylinders making 300 hp, now make 300hp with 8 cylinders, on the 8 cylinder each cylinder does not have to make as much power as a 4 cylinder.

Example, 4 cylinder engine, each cylinder makes 75 hp to get 300 hp total

8 cylinder engine, each cylinder makes 37.5 hp to get 300 hp total.

(assuming both engines redline at same rpm)

LS1NOVA

iTrader: (12)

People on this board have made 1000rwhp with 60's. Granted they had some meth and high base fuel pressure but it has been done. You will be fine for sure.

stealth1281

That's the rwhp range I am making if not slightly more...I still have the stock 2001 injectors which I was told not to change by the guy who rebuilt my motor or else the extra fuel could mix with the oil and blow my motor.....I was also told by my tuner that the stockers will not give my car enough fuel which will lean it out and that will blow it up too...

I guess what my question is, does your car have any issues running the stock injectors?

BrntWS6

iTrader: (7)

with that much HP the stockers will be too small. I'm running in the 430rwhp range and put in 42lb. The tuner has the ability to adjust them even further. I know you don't want to exceed like 80% of the duty cycle for injectors.

Don't put bigger injectors in until you get to the shop that is going to tune your car or you could have big issues.

ZL1Killa

iTrader: (17)

those 60# injectors will be fine.

ZL1Killa

iTrader: (17)

you would not have gotten away with 42# injectors. You would have needed at least 50# or so to meet the 85% duty cycle maximum.

750cc injectors are 71.36# injectors

my injectors are Injector Dynamics 725cc @ 43.5psi. I'm running them at 58psi, SO, 79.6# injectors at that pressure.
I'm making 650RWHP and 667RWTQ at 13psi at approx AFR of 11.4, this is with a 70% duty cycle. I'm turbo.

Those 60# injectors are 631cc rated. For your supercharged setup you will be fine as your BSFC is lower than my turbo setup. RCENG website. Technical Sizing.

Link to this at Fuel and injector sticky

Ask your buddy what his duty cycle is and what AFR he is running.
The above statement about cylinders & fueling & power is correct.
4 cylinders making 500HP takes a hell of a lot more fuel than 8 cylinders trying to make 500HP.




I do not know what motor you are putting this on nor what is done to it, but if it doesn't have forged internals & studded heads, I would recommend keeping the boost under 10psi, preferably at 8psi MAX