Yup! I was coming back to edit in the bit about the adjustable fuel pressure regulator. 
injectors
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Are you speaking of your '99? C5's have 26.4-29.1 pound/hr injectors standard. They are good for up to about 425 HP. Going with higher capacity injectors will do nothing for you sans other mods. If you change out to a higer capacity injector you will then need a reprogram on a dyno.
You might get more/better answers if you post in the C5 Tech section.
You might get more/better answers if you post in the C5 Tech section.
Last edited by 94z07fx3; Jul 28, 2007 at 10:58 AM.
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The stock injectors are either 21# or 22#.
There were a lot of people early on in LT1's who used ford #24 injectors. They were cheaper than the GM OE injector and some said quieter too.
Without a reprogram or a chip the car will run the same once in closed loop. This is because once the O2 sensors are hot the computer will sense the need to lean out the mixture. In open loop, however, the higher capacity injectors will be making the mixture more rich than normal.
IMHO one should take a comprehensive approach to performance modifications.
The 24# injectors could well be a part of a successful engine mod for example a 383 or a radical cam. But on their own I'd only consider them if I had failing injectors and future plans to build out the engine and reprogram.
There were a lot of people early on in LT1's who used ford #24 injectors. They were cheaper than the GM OE injector and some said quieter too.
Without a reprogram or a chip the car will run the same once in closed loop. This is because once the O2 sensors are hot the computer will sense the need to lean out the mixture. In open loop, however, the higher capacity injectors will be making the mixture more rich than normal.
IMHO one should take a comprehensive approach to performance modifications.
The 24# injectors could well be a part of a successful engine mod for example a 383 or a radical cam. But on their own I'd only consider them if I had failing injectors and future plans to build out the engine and reprogram.
Race Director
Joined: Dec 2006
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