Alright, so i threw on a tb from an 5.7L truck motor on my L03 and it runs much better. the hesitant and fluxuating idle is gone, and it just operates much smoother. the only problem is, if im romping on it pretty hard, at about 6 grand it cuts out, almost like a rev limiter or even like a speed limiter. i dont see it being much of a problem, because i wont shift it above 6 too often. i was wondering if anyone has overcome this problem, or even experienced it.
help much appreciated! julian

p.s. open element conversion with a k&n, so it should be able to get enough air to compensate for the 61# injectors.

 

Stock exhaust manifolds, stock cam, stock heads, stock intake, stock ECM programming, I SEE A PROBLEM. The stock setup is done by 4,500 rpm. Reving any higher than that is only going to make you slower. You need to open up the airflow through the engine and decrease the Base Pulse Width Constant BPWC in the chip to compensate for the larger 350 injectors. The stock TBI setups already run rich @ WOT and the 350 injectors just made you richer.

 

well its got flowtech shorties into an 80 series without cats, and a full msd ignition. i still know what u mean though. how would i go about increasing the BPWC, or should i just get an aftermarket chip? and as for a cam, people seem to be happy with the LT1 cam, so maybe ill just go that route.

 

Off the shelf aftermarket chip and even most of the mail-order "CUSTOM" tunes = GARBAGE

You will not be happy until you either have someone dial it in, in person or go the DIY route. There is enough information on this forum and the DIY Prom forum to get you started, if you have a laptop (even an ancient one)for about the price of a mail order prom you can be tuning.

BPWC is a value that is adjusted in the prom that relates engine displacement and fuel injector flow rates and adjust the base pulse width to the injectors.

 

ah ok, i understand now. in a typical gm tbi, theres a regulator thats just behind the 2 injectors. if you pull the top of the body off the unit, theres an adjustment screw thats blocked by a blob of copper. if the bead of copper is snapped off, you can adjust the screw, but i was just wondering what it does. i have no incentitive to boost psi lol, but i was just wondering what the screw actually does.

 

The screw raises and lowers the pluger that supports the spring. The spring works on the diaphram. Once the pressure of the fuel acting on the diaphram overcomes the pressure of the spring working against the diaprham, the relief passageway is opened up. Once the relief passageway is un-covered, fuel is bypassed back to the tank. As the pressure drops, the passageway is covered again. The regulator starts pulsing and the pressure is regulated. You can feel the regulator pulse many times a second. The screw adjust the tension on the spring. The higher you move the plunger, the more pressure against the backside of the diaphram, and the higher the fuel pressure has to be to overcome the spring. The stock spring generally adjust between 8 and 14 psi. At 14 psi the spring generally goes into coil bind and will rapidly become solid. When the spring goes into coil bind the fuel pressure shots uncontrollably higher.

 

There is really no reason to go above 5400-5500, above that you really not gaining anything, but losing