Can anyone give me some advice?? I have a 350 in my Camaro with a Weiland (i think that's how it's spelt?) High Rise Intake and a Holley 650 carb and I am wondering what should be a good setting at my fuel pressure regulator? It is as about 6 psi right now. Thanks.

 

4 to 6 psi is a good range.

Exactly which manifold do you have? Not that it affects the fuel pressure setting, just curious.

(BTW, it's Weiand.)

 

I'm not sure EXACTLY what intake it is from Weiand because I bought a parts car with the 350 and the intake already on the engine and the manufacturer's plate with the serial numbers and model numbers was pried off so it's very possible it was a stolen intake. Not for sure. Thank you for the advice!

 

The Holley needel and seat are good to 9psi before fuel starts literally pushing by. Set you FP at 8psi, depending on hp and pump anything less, if you had a FPG installed you will see a huge drop in pressure at WOT which WILL equate into a lean out condition and will slow your car down.

Mines been set at 8.75psi for the past 4 years with my electric pumps, and having run a few different fuel pumps and having a guage to witness what happens, I can tell you with a smaller pump I was down to 3psi (from 8.5psi) and it ran alright until 3rd gear (when the bowls are emptied cuz the pump could'nt keep up) 3psi at WOT is NOT acceptable. Start your pressure higher so you have room to lose some if using a less than adequate pump.

 

It would depent on the rest of the motor. Fuel pressure will vary and is part of the tuning process. It'll be different for every combination. Most of the motors I've had on the dyno like around 7-7.5 psi.. Anywhere in the 7-9 range is acceptable as long as the car runs properly.

 

I don't know how you can say that. As far as a carb is concerned, fuel level in the fuel bowls affects tuning, but it is not a tuning process. You may crutch another marginal condition with fuel level, but it isn't something you normally alter based on how it runs.

Fuel resupply is a different issue. You need to keep fuel going to the carb to replenish what is being used in order to keep the fuel level proper in the bowls. That is the only function of carb fuel pressure. If it won't keep the bowls full at a lower pressure, you may raise it to compensate, but if you have to set it so high to keep it full under power that it overfills at idle, you have a volume problem, not a pressure problem.

There are reports of cars with electric pumps at the tank that can't push hard enough against the weight of the fuel in the line under acceleration to keep the bowls full. Again, that's a pump capability problem, not a pressure problem per se.

For the typical street car with the typical Holley dual feed system, 4-6 psi should be adequate if everything else is in order.

 

Sorry, great one So you're saying that all carbed motors will run on the same FP? Granted it's not as critical on a carb as on a FI motor but there are variables that will differ with every combination. Not saying that your motor doesn't run optimal on 4-6 psi.

 

I think what he meant by typical street car is a non modded daily driver, it makes no power, thus needs no fuel.

 

Funny, that's exactly what I heard him say