FAST 39 lb/hr injectors vs. stock LS7 injectors
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I have been unable to find a rating for the stock GM LS7 injectors although I believe that I have read that it is 42 lb/hr @ 58psi. This is close to the injector flow rate value shown in the PCM code for a 2007 Z06 -- 41.74 lb/hr at 400 kPa (58 psi) pressure delta.
According to FAST, their 39 lb/hr injector (P/N 30397) is rated at the GM 4 bar or 58psi.
These injectors are for a 427 that will make 600 hp (flywheel). Using a BSFC = .45 and 80% duty cycle shows that an injector flow rate of just over 42 lb/hr is needed. Given that a 39 lb/hr injector may be too low, I will likely go to the FAST 50 lb/hr injector (P/N 30507). My desire to use the FAST injector is that it is the correct height and diameter and has the correct connector (USCAR) for my application - L76 intake with late model wiring harness. Can anyone recommend an alternative injector that would have this configuration and a flow rate of 42-50 lb/hr at 58 psi?
According to FAST, their 39 lb/hr injector (P/N 30397) is rated at the GM 4 bar or 58psi.
These injectors are for a 427 that will make 600 hp (flywheel). Using a BSFC = .45 and 80% duty cycle shows that an injector flow rate of just over 42 lb/hr is needed. Given that a 39 lb/hr injector may be too low, I will likely go to the FAST 50 lb/hr injector (P/N 30507). My desire to use the FAST injector is that it is the correct height and diameter and has the correct connector (USCAR) for my application - L76 intake with late model wiring harness. Can anyone recommend an alternative injector that would have this configuration and a flow rate of 42-50 lb/hr at 58 psi?
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I am not sure, but doesn't this injector have the minitimer (EV1) connector and o-ring diameter (at the manifold) common to C5 and F-body harnesses? The L76 and LS7 manifolds take the "shorty" injector having a larger diameter and USCAR connector. I've tried lots of different injectors in various cars and would like to find an injector which does not require the larger o-ring, fuel rail spacer and/or a connector adapter. It looks like my choices are the GM LS7/L92 injector or the FAST 50 lb/hr if I require a higher flowrate. If anyone knows of any other injectors that flow in the 45-55 lb/hr range and fit this intake I (and probably others who are making 650+ hp) would appreciate them posting.
Last edited by rennfahrerx; 01-24-2008 at 05:15 PM. Reason: for applications with more hp