Injectors too big?

For discussing injector selection,manifold modifications, throttle bodies, fuel supply system design and construction, and FIdle valves and IACs.
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hiperf402
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Injectors too big?

Post by hiperf402 »

I have a sbc 355 with twin turbos. Calculations called for 60 lb/hr injectors which I have installed. Problem I have is hard starting. Have to clear flood to get started. My ve analyze live autotunes cells at idle to 5's and 7's for 14.0 AFR and injector pw is around 1.2ms. Is this telling me that my injectors may be too big. Shouldn't my injector pw be around 3.4 or more?

SBC 355
Twin T04E turbos .63 a/r turbine and .60 a/r compressor
MSII running 2.891
Tunerstudio
Techedge wideband 02
Matt Cramer
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Re: Injectors too big?

Post by Matt Cramer »

I think you've set the opening time too high, so even with a pulse width equal to the opening time it's dumping in a bit too much fuel.
hiperf402
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Re: Injectors too big?

Post by hiperf402 »

Sorry for the delay Matt. I know you stay very busy. I uploaded my tune here. Could be way off though. I am still working on it.

Your thoughts on it are very much appreciated.
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hiperf402
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Re: Injectors too big?

Post by hiperf402 »

Don't know if these will help. Probably just trash.
Matt Cramer
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Re: Injectors too big?

Post by Matt Cramer »

Hard starting is going to be a matter of dialing in the cranking pulse widths. I see you've backed down the opening time; you'll probably need to retune that VE table now as it seems you have patches where it's running pretty much off the opening time and not the VE table.
hiperf402
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Re: Injectors too big?

Post by hiperf402 »

Thanks Matt. I'll work on it.
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