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almegaj
08-26-2009, 12:35 AM
My question is basically when do you determine (horsepower wise) when you have to upgrade to a bigger injector? Also will the stock fuel pump be enough volume for the 24lb injectors? I will either have to send my pcm off for a reflash or just go sct.

PeteRT
08-26-2009, 03:36 AM
http://kgparts.com/index.php?page=fuel-calc

google fuel injector calculator. i'm getting about the same regardless of which one i use.

iirc, some have said the stock injectors (the 19lb/hr ones) are good to 350 or so hp.... i really don't know.

for a tune, i would go sct, and am planning to once the blower makes it from the shelf onto my engine.
pete

ducrider
08-26-2009, 03:54 AM
Injector flow rate in lbs/hr is a relative term because of the fuel pressure used to rate them.The 19 lb/hr injectors can supply enough fuel for a good bit of HP.You need to raise fuel pressure to keep up the flow.Using bigger injectors in performance applications is done to keep up the demand of fuel at lower pressures(stock psi).I did a good bit of research when looking at injectors for a turbo car I had many years ago.Turbos are apples to the oranges we are talking about.With out fuel system mods stock injectors limit how much HP you can make.With a modded fuel system the stock injectors can handle a good bit.

almegaj
08-26-2009, 01:54 PM
So I should just keep the stock 19lb injectors in place even though I will be going with cam, heads, intake, tb, cai, stall, gears, roller rockers, n20, headers, exhaust, pcm. As of now with those mods minus the cam and heads my spark plug was white and light grey on number one plug. Hey Pete were did you get your viper stall at?

Intense RT
08-26-2009, 02:54 PM
So I should just keep the stock 19lb injectors in place even though I will be going with cam, heads, intake, tb, cai, stall, gears, roller rockers, n20, headers, exhaust, pcm. As of now with those mods minus the cam and heads my spark plug was white and light grey on number one plug. Hey Pete were did you get your viper stall at?You're fine, my plugs have looked like that for 3 years.