Jeff Smith

iTrader: (44)

what is fuel pressure PSI normally for LS2 carbed?
0-15?
0-30?
0-60?

team39763

iTrader: (3)

I always thought most carb applications ran 4-6psi. I try to run about 6psi with mine.

bluethunder364

iTrader: (5)

I have mine set at around 8 PSI with the gauge at the regulator. Seems to work fine for my particular set-up

rojs234

iTrader: (5)

There is nothing actually WRONG with running 8 lbs. fuel pressure. If you are running a high horsepower motor that is having trouble keeping the bowls full, it is definately the plan. But why take a chance on washing the rings out on a street motor? The Holley or Demon are able to control this pressure. Most carbs can't. Since fuel pressure has absolutely nothing to do with the way a carb meters the fuel air ratio, you could run 2 lbs. if it would keep the bowls full. The fuel has to be at the right level in the carb for it to do it's job correctly, but most carbs can do this with .093 needle seats and around 6 lbs. pressure. Also, you are not at the limit of what the float can control and there is not as much chance of extra fuel blowing past the seats and upsetting your mixture settings or spilling over into the motor and damaging the rings. Just my $.02 worth . Ron

bczee

iTrader: (12)

Agreed with 4-6psi for normal driving/street, 7-8psi for strip/racing application.

Having the correct CFM size and correct pressure for the Carb to function correctly is more of a concern as in relationship to the displacement of the engine and load.

forcd ind

iTrader: (7)

are you looking for a fuel gauge? the non boosted carb on an ls engine is no diff than any non boosted carb'ed engine-set it at 6 lbs

deathbyspoon

iTrader: (1)

I'm looking at 5-6 psi in mine.

Jeff Smith

iTrader: (44)

Probably>> Summit racing #800215 0-15 PSI..Cost $19

Jeff Smith

iTrader: (44)

I talked with Wegner Motorsports, Average 8psi (normal 6-10 psi)

bluethunder364

iTrader: (5)

I can assure I have no fuel spill into the oil, and yes I do drag my car and it can keep up with the 8psi just fine. Keep in mind that most set-ups are not the same and have different requirements. Fuel pressure gauges should be set-up so you can see them, If you do inside the car you need an isolater that would prevent fuel from coming in should you have some failure with the line. Or set it up so it can be seen through the windshield
to see if you maintain your pressure when under a hard load. Start at a lower setting and see how you do. You can also see how your fuel pump is doing .

holley505

iTrader: (1)

6 lbs here

Jeff Smith

iTrader: (44)

[QUOTE=bluethunder364;10001129]I can assure I have no fuel spill into the oil, and yes I do drag my car and it can keep up with the 8psi just fine. Keep in mind that most set-ups are not the same and have different requirements. Fuel pressure gauges should be set-up so you can see them, If you do inside the car you need an isolater that would prevent fuel from coming in should you have some failure with the line. Or set it up so it can be seen through the windshield
to see if you maintain your pressure when under a hard load. Start at a lower setting and see how you do. You can also see how your fuel pump is doing .[/QUOTE]

Can you show me the pix of where the F/P mount set-up so can see.
What I need to have the hose/fitting to dash-in from carb?

cutlass_455

iTrader: (2)

2 lbs probably would not be enough in an LS2 car thats gonna see track time. The G force alone would keep fuel from making it to the carb. Thats why 7-8# is recommended, it overcomes the G's of the launch.

But for cruising I think you're right, 2 # is plenty, unless you ever want to accelerate.

rojs234

iTrader: (5)

I guess I am not very good at explaining things. I seem to have ruffled *bluethunder364* 's feathers with my first post and if I did, I truly apoligise. I was trying to make the point that most engines don't require high fuel pressure. I also was NOT saying that you should run 2 lbs. Just because you have an LSX engine does not mean it's fuel requirements are any different than any other carbureted engine. The purpose of a fuel pump is to keep the float bowls at the correct level so that the carb can meter the fuel correctly. In a high horsepower street engine or a race engine you sometimes have to run a higher pressure (within reason) to keep up with the requirements. My concern was with some of the new to the hobby or inexperienceed tuners who always think if a little bit is good, a whole lot would be better!! If I remember correctly, Holley sets their street pump at 7 lb. Edelbrock states in their manual that they ship with their carbs, to set the pressure at a max. of 5.5 lbs. Most earliar mechanical fuel pumps were self regulated at around 6 lbs. or less. AS I said in another post, you pay your money and you get to choose. Ron