Fuel Pressure ?
Fuel Pressure ? Plesae explain how higher Fuel Pressure increases performance. What pressure should one be at w cc-502, 58mm TB, mildly p/p heads, gasket matched to intake, Ram Air, 30lb SVO, A-4, LT w 3" exhaust, no cats, 3.42 and suspension upgraded. Pressure is adjusted by the fuel regulator and not the PCM, correct?
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I haven't tried on a LT1 yet, but my TPI with AFPR responded to higher and lower pressure. Everyone here says the LT1 doesn't, but I don't believe it. The higher pressure is going to increase the injector flow. Thats where everyone says the PCM will compensate pulse width. But if you have a tuner, then just put in 1 more # over whatever you're running. If I had $60, I'd pick up the one for my car. Plus, you know you have a new regulator then if it's already old 
Originally Posted by Formula350
I haven't tried on a LT1 yet, but my TPI with AFPR responded to higher and lower pressure. Everyone here says the LT1 doesn't, but I don't believe it. The higher pressure is going to increase the injector flow. Thats where everyone says the PCM will compensate pulse width. But if you have a tuner, then just put in 1 more # over whatever you're running. If I had $60, I'd pick up the one for my car. Plus, you know you have a new regulator then if it's already old
Although not an expert, I will try to explain what I do understand.
The PCM adjusts the fuel flow to 14.x during closed loop operation, no matter the fuel pressure or the size of the injectors. It must be told the size of the injectors fairly accurately, and is adjusted with a tune.
During open loop operation, it uses the PE tables and the MAF table, which must also be adjusted with a tune. I have heard of cases where a slightly higher fuel pressure increased power without a tune.
In order to regulate pressure, you will need an adjustable fuel pressure regulator.
