Fuel PSI Gauge ?

[67chevemall]

Hello

I have a edelbrock 1406 carb with a holley regulator and Mr gasket gauge.

I hear one should run the PSI at 4-6 on these carbs.

Is this at WOT? because if I set it at idle then when I throttle it the psi drops to almost nothing on the gauge.

I find it runs better up around 10psi

I think I'm missing something here

Any Ideas?

[poorboy]

The reg should make the pressure constant through all rpms. I've always ran 7-9 on mine. If 10 is where it runs the best and it's not flooding then I would leave it there. What kind of pump are you running?

[67chevemall]

stock mech. pump

I was thinking maybe the motor pings because it isn't getting enough fuel

[poorboy]

The motor could be pinging because of bad fuel or your timing could be off. With it set oa 10psi will it hold that trough all rpm's? If not I would look into replacing the pump.

[corn]

A stock mechanical pump is @ 3lbs isnt it? What is there to regulate?

[70c10]

I think stock is in the 6-7 psi range but maybe I'm wrong.

[67chevemall]

Maybe my gauge or reg is f ed then. Stock pump and I have to turn the reg almost all the way in to get it down to 4-6psi even taking off the nut that locks the setting in.

I'm going to try it with out the reg.

[piecesparts]

The 1406 needs to be kept below the 9 psi that a lot of street electric fuel pumps put out and that is where a regulator would be needed. The mechanical pump will operate and create the 6-7 psi that the carb needs and works just fine. The use of a fuel regulator here is a definite waste. It is just another item in the fuel line that is restricting flow to the carb. If you want to do anything, then setup a return line to your tank and get a fuel pump that has that port already designed into it. It will be a small orficed fitting that has a 1/4" line to allow flow back to the tank. this was used on later model trucks and was not an item used in this era of trucks.

[bryanw1968]

Originally Posted by piecesparts

The 1406 needs to be kept below the 9 psi that a lot of street electric fuel pumps put out and that is where a regulator would be needed. The mechanical pump will operate and create the 6-7 psi that the carb needs and works just fine. The use of a fuel regulator here is a definite waste. It is just another item in the fuel line that is restricting flow to the carb. If you want to do anything, then setup a return line to your tank and get a fuel pump that has that port already designed into it. It will be a small orficed fitting that has a 1/4" line to allow flow back to the tank. this was used on later model trucks and was not an item used in this era of trucks.

piecesparts,

I am currently running a carter performance mechanical pump that is high volume/low pressure so I am currently not running a regulator. The pump does not have a return and the truck obviously didn't come with lines for it.
What am I gaining by going to a pump with a return setup?

[piecesparts]

Originally Posted by bryanw1968

piecesparts,

I am currently running a carter performance mechanical pump that is high volume/low pressure so I am currently not running a regulator. The pump does not have a return and the truck obviously didn't come with lines for it.
What am I gaining by going to a pump with a return setup?

I commented that IF and ONLY IF, one was to do something about the fuel pump, then running a return line would give them a relief pathway.

Last year I put an Edelbrock "Street" performance fuel pump on my truck along with a Thunder AVS carb. This motor is a 383 stroker motor and it had problems when I ran it on city streets for a period. The motor would "BOG" when I accelerated to get onto a highway or when I jumped on it at a light. However out on the highway and any other time it would not bog at all. I had changed the fuel line and the fuel pump when I installed the 383 motor rebuild and the bog started at that time. Up to that time the truck, with 200,000 miles, never had this issue and I had been running a factory designed fuel pump that had the return line. My truck is an 84 SWB, so it came with the return fuel line in the truck's design. The bogging issue would not correct itself, so I started at the first item that I had changed during the rebuild, which was the pump. I took the bottom off of the pump and installed the Edelbrock bottom feed plate conversion and then installed an orficed fitting and the return line was then reused. This allowed a very small amount of fuel to return to the tank and keep the pump from having any heated fuel issues. Amazing the "BOGGING" went away. I do associate this with the fuel in the pump getting to warm and vapor-locking the pump until I got out on an open road and flushed it out by running the truck harder. That is why, I suggested the return line.