Injector Size for 600hp
Thread Starter
Burning Brakes
Joined: Sep 2003
Posts: 875
Likes: 0
From: Louisville KY
Injector Size for 600hp
I'm probably beating a dead horse here, but ive seen some conflicting information dealing with what pound injectors to use in an app like mine. If my combo is a n/a 600-620hp engine, what type of injectors should i use and retain the 80% "rule". I plan on auto-xing and taking it to the strip every once and a while and I do plan on using the power so i don't want to have an injector that I will push to hard yet I don't want too much. Would psi should I run in the rails as well (fuel pump suggestions)? This is in a 1984 corvette, so pretty much everything is custom. Thanks
Safety Car
Joined: May 2003
Posts: 3,814
Likes: 105
From: Dearborn Heights Michigan
I have a formual for LS1's. Take it for what it is worth.
Injector size (lbs) = FWHP/ (2.04 times 8). / is divide by sign This is at 100% duty cycle.
Fred
Injector size (lbs) = FWHP/ (2.04 times 8). / is divide by sign This is at 100% duty cycle.
Fred
Last edited by FKING1; Nov 11, 2005 at 05:17 PM.
Thread Starter
Burning Brakes
Joined: Sep 2003
Posts: 875
Likes: 0
From: Louisville KY
Using that formula I came up with right at 38# injectors. I'm still lost on the duty cycle thing though. Can you expound? I know more people have 600hp cars and rund more than stock injectors. I'm trying to get multiple thoughts on the issue.
Burning Brakes
Joined: Dec 2004
Posts: 1,117
Likes: 0
From: New England
Originally Posted by kpforce1
I'm probably beating a dead horse here, but ive seen some conflicting information dealing with what pound injectors to use in an app like mine. If my combo is a n/a 600-620hp engine, what type of injectors should i use and retain the 80% "rule". I plan on auto-xing and taking it to the strip every once and a while and I do plan on using the power so i don't want to have an injector that I will push to hard yet I don't want too much. Would psi should I run in the rails as well (fuel pump suggestions)? This is in a 1984 corvette, so pretty much everything is custom. Thanks
Thread Starter
Burning Brakes
Joined: Sep 2003
Posts: 875
Likes: 0
From: Louisville KY
60#???? good god man! 
I don't plan on doing any "growing" once this build is done and I figured the most i would need would be around 42# or so. I think around 510-520 RWHP is PLENTY for what i'll be doing... I’m already into the holy sh*t zone where tires just disappear, rear ends miraculously turn into apple sauce, and ricers don't even bother at the stop light... 
I don't plan on doing any "growing" once this build is done and I figured the most i would need would be around 42# or so. I think around 510-520 RWHP is PLENTY for what i'll be doing... I’m already into the holy sh*t zone where tires just disappear, rear ends miraculously turn into apple sauce, and ricers don't even bother at the stop light...
Burning Brakes
Joined: Dec 2004
Posts: 1,117
Likes: 0
From: New England
Originally Posted by kpforce1
60#???? good god man! I don't plan on doing any "growing" once this build is done and I figured the most i would need would be around 42# or so. I think around 510-520 RWHP is PLENTY for what i'll be doing... I’m already into the holy sh*t zone where tires just disappear, rear ends miraculously turn into apple sauce, and ricers don't even bother at the stop light...
I don't plan on doing any "growing" once this build is done and I figured the most i would need would be around 42# or so. I think around 510-520 RWHP is PLENTY for what i'll be doing... I’m already into the holy sh*t zone where tires just disappear, rear ends miraculously turn into apple sauce, and ricers don't even bother at the stop light... 
Thread Starter
Burning Brakes
Joined: Sep 2003
Posts: 875
Likes: 0
From: Louisville KY
Originally Posted by SS930
I'm sorry, I thought you had said 600-620 rwhp, not crank hp. For only 510-520 rwhp a set of 42's will be just fine.
its all good. I figured thats what you had thought. I like the "only" 510-520 rwhp comment too. You have to have a F/I setup dont you? I remember when 400 at the crank was more than enouh and now i have this beast going into my C4 vette. Any other thoughts on the 42# injectors? Smaller? Bigger? Thanks again
Burning Brakes
Joined: Dec 2004
Posts: 1,117
Likes: 0
From: New England
Originally Posted by kpforce1
its all good. I figured thats what you had thought. I like the "only" 510-520 rwhp comment too. You have to have a F/I setup dont you? I remember when 400 at the crank was more than enouh and now i have this beast going into my C4 vette. Any other thoughts on the 42# injectors? Smaller? Bigger? Thanks again
Don't second guess the 42's they are GREAT injectors... they drive like stock.
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