Hey guys i'm wondering if anyone else had the problem of not being able to get they're fuel pressure lower then 7 psi with this regulator for use with a carberator and the stock fuel injection in tank fuel pump?

I went ahead and asked the tech at Mallory about the problem and his response was:

"You need to increase your return line back to the tank with 1/2" fuel line. you are suing the stock return line that is probably a 5/16" and is too restrictive to allow the pressure to be adjusted down properly. With a 5/16" return line and a 10 foot return, the back pressure is 7lbs so this is what you have to correct. With a 1/2" line the pressur will be 1.5 lbs and you can work with this pressure."

I have to give some credit to Mallory for they're quick and detailed response to my question (within 5 minutes).

Now, I have to rerout my fuel lines anyway because they are on the drivers side. What tubing do i use from the fuel pump to the engine and do i need to drop the tank to do the job? What fittings will I need to attach the lines to the pump?

Matt

------------------
89 Camaro IROC
350" GM Crate Motor
278/290 .476/.494,
3000 Lockup Converter,
..plenty more
Harwood 2" Cowl

UNITED WE STAND

 

I had this same problem when I set up my fuel system in my Z.I ran -6An (3/8") braided from tank to regulator to carb and -8an (5/8") braided from return port on regulator to tank.I modified the stock sending unit to install bigger return line and then hooked up the braided line to that.After that I can lower my pressure to 1psi if I wanted to.I am running a Holley Black Pro series pump on my car but I have a friend that runs an identical setup on his ex TPI car with a Walbro in tank Fuel pump.Also be sure to bleed the fuel system of air at the regulator by removing the adjustment nut and screw totally and turning on the fuel system,after it comes on and the fuel is flowing reinstall the screw and nut and set the pressure.This has caused me many a headache also.

------------------
1982 Z28:355,4 Speed,Lots of bolt ons

 

Onebad, where do you have your AFPR mounted? i was looking at possible locations on the passenger side but can't decide. Second, WOW! You sure went all out with the braided line from the pump to the regulator. Jegs has each line for almost 200 bucks. I also saw the aluminum line it looks like thats what i'm going to have to get and run it that way. I'm probably also going to need a bender of some sort. How hard is it to drop the tank? I'll need to drop the rear i would assume. How do i keep the springs from shooting off. While i'm there i might as well replace my worn out fuel sender... Thanks man

Matt

 

I have the regulator mounted on the passenger side strut tower right behind the strut mount.Stay away from the aluminum line,it corrodes and cracks real easy.I have seen to many aluminum lines leak at the fittings too.Either run steel line or look into Aeroquip push lok hose and fittings (NHRA legal),this is another route to go and cheaper than braided,about half the price and no bending needed.Unbolt the shocks and jack up the back of the car and the springs will fall out,no danger there,but watch the rear brake hose(from car to rear),you can only get so much room before it will be extended all the way.Then you have to remove the exhaust and drop the tank,not that hard.I have done it on a lift and on my back on a dirt driveway,still not to hard.

------------------
1982 Z28:355,4 Speed,Lots of bolt ons

[This message has been edited by onebad82z (edited December 07, 2001).]