Fuel pressure and Edelbrock carbs

I've checked some of the past posts on this issue, but can someone tell me-- are Edelbrock carbs (600 cfm vac. secondary, electric choke on a SBC) THAT sensitive to fuel pressure?

I'm pissed. I've been having issues with fuel pressure and this carb, which is almost brand-new. Last summer, I put a cheapo NAPA mech. fuel pump on my 327. Ended up with it flooding and being a bitch to start every time I shut it off. Today, I put in the best mechanical fuel pump NAPA had. Same problem--drive for 15 or 20 minutes, shut it off, then it blubbers like hell when I try to start it up again.

I was trying to avoid putting on a fuel pressure regulator b/c this was never an issue when I had a Quadrajet on it, but it looks like I've got no choice at this point. If I do, should I go with the low-pressure Holley (1-4 psi) unit? Will this take care of it?

Thanks all

 

The last elcheapo NAPA pump I used put out 9 lbs. Carburator no likey.

Parts store fuel pumps are a crapshoot as far as pressure. Usually an AutoZone 13 dollar pump does about 4 psi, but you never really know without a guage.

BUT. Before you plumb a regulator into your system, have a very close look at your float level. Also, there is a spring in the needle and seat that you can strech to give you a little more resistance to pressure, but I bet you are looking at a too high float level.

Good luck, -Abone.

 

edelbrock carbs do not like more than 6 psi. You should put a pressure tester on it before you do anything.

 

Any new carb should be disassembled and checked for factory crud in the float bowls. Then, mount the Edelbrock on a heat sink spacer, to keep it away from the fuel boiling heat. I have run several edelbrocks, and never seen one do what you discribe unless it was not on a spacer.

 

I woud'nt run but about 6-7 lbs. pressure with that carb. I had a 750 eldlebrock on mine and it wanted to stumble and flood a little after after an extended run on the freeway when you got off. Put a 1 in. spacer between the carb and manifold to keep the fuel from boiling from the hot engine. Problem solved.

 

I've run both carter's and edelbrocks carbs on mill's, (same carbs' made by Weber). Two mill's with dual quads naturally aspirated, and one dual quad blower motor..
ALL of them needed a fuel regulator. I set it between 5 and 6 lbs and never had a problem..
But prior to running it, i had a lot of issue's with the car's stumbling and just about stalling when you stopped at a light. All were stick shift car's, and when you would throw in the clutch when you were coming to the stop, it would idle down and load up because of the excess fuel being pushed past the needle and seat. You'd have to throw it in neutral, release the clutch and brake with the left foot so you could keep the motor clear..REAL pain in the ass!!
I had even talked to the tech people at edelbrock and they told me straight out to install a regulator and this was the cause of my problem.
NO exageration at all, installing the regulator solved this problem completly..
I'd use the better quality regulator though, not the Napa style with the turn dial on it. Ive had shitty luck with those.
my 2 cents.

Tony

 

I'm with 4tford. My neighbor has a 302 that we put an Eddy on to replace a Holley (it was old and nasty). With the mechanical Carter fuel pump, the car ran like ASS. We went back to the speed shop with a "what gives" look on our faces, and were told "no more than 6 psi, preferably 4-5". So we set it at 4.5 and it works great. PS, we're using a Holley regulator, not a NAPA.

Your mileage, of course, may vary.

Jay

 

So today, I take the pickup in to the local garage (good ol' boys that understand this kind of stuff and do tons of carb work) to do a fuel pressure test. I had previously plumbed in a small shutoff valve from the local Ace Hardware in an attempt to cut down fuel pressure. Their results: with the valve in the wide-open position, the stock Napa fuel pump was putting out 10 PSI. With the valve cut back considerably, it was still making 7 psi at idle. The guy who worked on it thought it may be a needle/seat issue, but it seems to me that 7 psi is still gonna cause problems based on what I've learned about Edelbrocks here. I'm pretty sure I'll just put in a fuel pressure regulator that can cut it down to 4-5 psi.

As an aside: I know Edelbrock makes an "off road" needle and seat setup that has a spring that's designed to keep the needle closed when things get rough. Would it be advisable to add this, as well? Would the extra spring pressure on the needle help this problem at all?

 

You might use a regulator but if you just put an insulator between the carburetor and the intake you will solve 90% of your problem. It don't have to be a thick spacer, just a 3/8" insulator gasket will do and you won't have to replace your mounting studs with longer ones. Just as Don said the heat causes perculation and that boils your fuel. Listen for the gurgle after you shut it off.
the Dickster