rattbird1989

I bought a chevy 5.7 350 (L05) it came out of a 1989 SUBURBAN, to replace my 305 TBI in my 1989 FIREBIRD FORMULA w/ 5-speed, I had the 350 (L05) overhauld Board .30 over, deck shaved ect. the shop also put in a
"mild cam" (cant remember the cam's stats)
Now list of motor parts installed on 350.

1. Summit stage 1 Duel rise intake
2. Edelbrock performer 1406 600cfm
3. Hooker headers to Y pipe No Cat (keep that on the DL) 3" pipe to magna flow muffler

Everything else on the motor is stock!

Still running the stock fuel pump to Mallory Return REG

so she runs fine has good pull at half thottle but when i open her up she not getting enough FUEL i even raced my buddys 1989 firebird formula 305 TBI (stock) and LOST305 vs 350 and lost hmmmmmm so my friend tells me to get a Machcanical fuel pump, he said my 4 barrles or not getting the fuel i need so my ? is will this solve my problem or is my engine just a turd it took me 5 years to come this far just to lose to the motor i got rid of pls help any thoughts PLEASE

HawkZ28

iTrader: (2)

First problem is that triangle air cleaner. That kills performance as fast as Casey Anthony does kids.

The parts store OEM style replacements don't provide enough volume IMHO. I had a brand new one that couldn't supply enough for my built 305. Switched over to a Holley 130gph pump, and problem solved.

Did you tune the carb according to Edelbrock's guide? I would replace the fuel pump only after doing so....

rattbird1989

My friend tuned my carb and i went threw the manual that came with the carb its all latin to me but still no pull at WOT. it makes this low humm and slowly climbs up to speed, but at half thottle she has some mean pull, i have my summit mechanical fuel pump next to me P/N Sum-2500020-1 3/8 in and 3/8 outlit 110gph think that will help?
i am gonna install this Saturday if that dont fix it iam gonna pull my hair out, when i first got her people said get rid of that 305 and go with a 350, funny now a 305 is walking all over me. do i need to maybe get a carb kit maybe or is my engine that much of a monster that i need a bigger CARB!!!!!!!! also should i test run her with out that air cleaner and see if that helps

HawkZ28

iTrader: (2)

Did your friend follow the directions correctly, in order? There is a section in the manual that translates from Latin to English

If you've already purchased it, it can't hurt. What is your fuel pressure regulator set at? Too much/not enough pressure can cause issues.

Your 350 is not too big or wild for that carb.

A $15 parts store air cleaner setup would be a vast improvement over your current air cleaner.

midias

As others have said ditch that pile of crap air cleaner.

The 600 should be fine I run the 1405 on my 355 with no problems.

Other than that are you linkages correct?
Is you choke operating correctly?

I would take off the air cleaner and have a friend push the gas pedal to make sure everything is operating as expected.

Also what is your timing set at?
How was it set?

InfernalVortex

iTrader: (4)

I I dont think tis the fuel pump. I got a stock pump on my Holley 650DP and it runs just fine. There's already fuel in the bowls. It's conceivable that you'd consume more than your pump can handle (But it's just an L05, it aint exactly a huge cammed 383) but I dont think your motor can use up all the fuel in your fuel bowls before you get to 3000 RPMs.

Sounds like a carburetor issue to me, but I know nothing about the edelbrocks so I'll leave it be.

And ditch the Triangle O' Death.

rattbird1989

As for my Fuel Psi its at 5.5 ideling but when my friend revs it, the Psi drops to 4 - 3 psi so thats seems likely to be a issuse dont know alot about carbs and the first chance i get the air cleaner is comeing off. hopefuly this Sat were gonna tool with ill keep you posted as to the result of the machincal fuel pump making any changes

InfernalVortex

iTrader: (4)

Are you using a decent 3-port return style regulator?

Edit:

I just saw the pics, looks like a decent Mallory unit to me. Looks pretty well-done too.

I'd hesitate to just swap to a mechanical pump. There are a lot of reasons an electric pump is better.

rattbird1989

the in-tank pump has pushed about 190,000 miles worth of fuel and 5,000 of that was with a "dead head" style REG so iam sure that in-tank pump is getting tired. my friend swears up and down kicking and screaming that this machincal pump will solve my problem we shall see Saturday

InfernalVortex

iTrader: (4)

Id replace the in-tank pump. To properly setup a mechanical pump you'll want to remove the intank pump anyway, so it's not like its a lot of extra work.

HawkZ28

iTrader: (2)

I could be wrong, but your cam probably doesn't even have the pump eccentric lobe to run a mechanical pump.

InfernalVortex

iTrader: (4)

I know some of the 90s L05's dont even have a fuel pump pushrod channel at all. It's just a rectangle that's filled in. But his is an 89 block so maybe it does.

rattbird1989

i checked my block and took off the plate where you would bolt on the pump and there is a hole that a fuel pump push rod would fit but how would i know if my Cam would work?

HawkZ28

iTrader: (2)

disconnect the wiring from the distributor. have a friend rotate the engine while you insert a push rod through the hole as it contacts the camshaft. as the engine rotates you should feel the push rod move roughly half an inch. if no movement is felt you do not have the eccentric lobe.

Fast355

iTrader: (2)

Converting to a mechanical fuel pump is an excersice in futility, three words... DON'T DO IT!!! I highly doubt its the problem.

rattbird1989

well just removed the fuel tank, removed the fuel pump and installed a carb pick-up, my cam has eccentric lobe now its just a matter of moving around some AN steel fuel line, so this is not gonna be to bad plus i have a extra 6' of it, i really love that stuff and ill never have to drop that tank again EVER!!!!!!!!! fingers crossed. but as for the WOT i advanced my dizzy and that really seemed to help so tomorrow ill hook everything up and TUNE TUNE and TUNE that motor, plus i bought a pair of 1996 V-tec heads for dirt cheap... Carbs and mechanical fuel pumps go hand and hand

jahblah

LMAOOOOOO good example and it gets away with it all the same as many people I see with them still