[pimpdout98gt]

should i have any problems with my setup being blowthrough w/ pmas meter calibrated for 42 lbs. injectors and running 20 p.s.i. through a novi 2000 on a 98 gt with npi heads? what i'm concerned about is pushing that much boost with those size injectors, but being npi won't let me clear 450 rwhp, which is a good range for these injectors rated for 450-550. just wanting to know if i "NEED" to upgrade to 60 lbs. injectors or am i good with 42's.

[~C~]

i thought anything over 12 or 15 lbs you need 60lbs. not sure though.

[TurboLX]

gonna need to get it re-calibrated

[pimpdout98gt]

are you talking about my mass air flow sensor, and why would i need to get it recalibrated?

[TurboLX]

disregard my last post, i didnt read the full post

42lb injectors are not capable of supporting 20psi

[~C~]

Originally Posted by TurboLX disregard my last post, i didnt read the full post 42lb injectors are not capable of supporting 20psi

thats what i thought. you need 60lb injectors.

[pimpdout98gt]

so you don't think that 42 lbs. injectors will be able to support a supercharged engine producing 20 p.s.i. of boost through non p.i. heads even though the final power output to the wheels is within the horsepower range of the specific injector range? i.e., 42 lbs. fuel injectors will support from 450 h.p. to 550 h.p. and 60 lbs. fuel injectors will support from 550 h.p. to 700 h.p., etc.

[pimpdout98gt]

another question is how does boost dictate fuel injector sizing even though you reach a certain h.p. level to the wheels? i thought once you've reached a certain power level, that would dictate which size injectors you would use. if i did decide to switch to 60 lbs. injectors would i have to have my blow through maf recalibrated or could i just use it even though it was sent to me calibrated for a specific size injector?

[Trick Tuners]

Originally Posted by pimpdout98gt another question is how does boost dictate fuel injector sizing even though you reach a certain h.p. level to the wheels? i thought once you've reached a certain power level, that would dictate which size injectors you would use. if i did decide to switch to 60 lbs. injectors would i have to have my blow through maf recalibrated or could i just use it even though it was sent to me calibrated for a specific size injector?

You should really get tuned properly and not mess around with "calibrated" mafs. Switching a maf to blow thru will throw its calibration way off. You need bigger injectors because at 20psi you have increased resistance to the injection. The more boost you run the higher you need to size the injectors, because the flow drops as the boost goes up. Injectors will support WAY more hp on a NA motor than a high psi boosted motor. I have a set of 60# S/D injectors with the EV-1 harness on them for $339
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