Fuel Pressure
 

I have a 1999, 29' Baja Outlaw. The motors have Edelbrock aluminum heads, EMI Thunder exhaust, Edelbrock Victor intake with Holly 850 carbs. Fuel pumps are Edelbrock 120gph pre-set at 6 1/2 psi. The fuel pressure holds 5-6 psi untill WOT where it drops to 3 psi. Is this ok, or should it hold 5-6 psi all the time? Thanks for any help you can offer. Sure would hate to melt pistons, but sure do love to run WOT.

At WOT you should have always 7-8 psi with a carbed engine.

Even 5-6 is to low.:eek:

Time for a new fuel pump or turn up the pressure on the old one if you can . :ernaehrung004:

Pumps pre-set
 

These pumps have no adjustment. They are pre-set at 6 1/2 lbs. Looks like I need to buy bigger pumps with regulators, kinda what I thought. Thanks guys.

My mechanical Pump is a Holley and has a preset press of 7-9psi ,dont need a regulator. Works perfect.
JEGS or SUMMIT has them for around 85 bucks.

I run the race pump for carb pumps never drops and way over half the fuel pump rod pressure I think it is racepumps.com

I have similar fuel pressure readings on my carbed 454.
Can anyone describe how the low psi numbers translate to performance?

Does it just run out of power on the top end smoothly? or does it sputter, break up and run like crap?

Sorry for the sidetrack, but this seems related.

If you have low fuel press on a carbed engine it will lean out the motor due to not geting enuff fuel into the fuelbowls and that will cause burned pistons and sofort.
because know your sparkplugs egniht without fuel in the chamber.:eek:
So basicly you will not make the power on either end of your powerband, because the chamber is not filled with fuel all the way.
Also the engine overheats alot quicker since the fuel is not cooling the valves.

Daredevil, thanks for the reply.
My 454 runs smoothly all the way up to about 4900 or so where it plateaus.
It never seems to miss a beat. I've often wondered if it was "gently" starving on the upper end.

So a new fuel pump with strong pressure could unleash horsepower I didn't know I had?

like i said with a carbed engine you wanna see 7psi min. at WOT.