[Formula400NYC]

I remember seeing Tom V. post a diagram for the right way to plumb a return style system. It was a while ago though, I tried a search and came up empty. If anyone has it, I would appreciate it. Or possibly, Tom V. could repost it. It's for a second gen and I would like to get it right the first time. Thanks all...

[MrPushrod]

Originally Posted by Formula400NYC

I remember seeing Tom V. post a diagram for the right way to plumb a return style system. It was a while ago though, I tried a search and came up empty. If anyone has it, I would appreciate it. Or possibly, Tom V. could repost it. It's for a second gen and I would like to get it right the first time. Thanks all...

cell-filter-fuel pump-filter-regulator-carb
Then your return line will come off the regulator back to the cell.
Easy.

[steve]

regulator needs to be close to the CARB, right. pump needs to be near CELL. that means an extra 8-10ft of stainless 8an line !!!!!! $$$$$

[MrPushrod]

Originally Posted by steve

regulator needs to be close to the CARB, right. pump needs to be near CELL. that means an extra 8-10ft of stainless 8an line !!!!!! $$$$$

Yep, also remember the pump is gravity fed. Install under the tank.

[Formula400NYC]

Is the return regualtor woth the extra hassle and expense? Hopefully the car will see plenty of street time...

[MrPushrod]

Originally Posted by Formula400NYC

Is the return regualtor woth the extra hassle and expense? Hopefully the car will see plenty of street time...

hell yes, consistant pressure, pump lasts longer, quieter and no pressure
creep. Spend the money and do it right the first time, don't make my
mistakes.

[speedshopmike]

for a street car with a big pump, return style is the only way to go.
aside from more stable fuel delivery, your pump will last longer and run quieter.
your tank may also be plumbed factory with a return line already conveniently installed; my 81 did.
and it's now the regulator return line.
if you're using a cell, be sure to return fuel away from teh pickup, and where it won't aerate the fuelmaking bubbles.

[speedshopmike]

-8 is quite adequate for most street cars for a feed line.
you cant really have too big a return line.
and bigger feeds will allow headroom for go-faster-later, as you mentioned.

[Formula400NYC]

Thanks guys, I am gonna go with the Mallory 140 pump and the return regulator with -8 line on both sides. Factory tank with a sump. This should be more than enough for bottom 11's..

[Tim Corcoran]

Go on the Mallory web site and read their installation instructions and the tech bulletins for Mallory 140 pump and 4309 bypass style regulator. I thought I could get away with a 1/2" (-8) feed and a 3/8" (-6) return but no way. According to the Mallory tech bulletin with the regulator backed off all the way the back pressure (gage pressure) needs to be 3 psi or less. With the 3/8" return line my back pressure was 6 psi. So I took out the 3/8" (-6) return line and replaced it with a 5/8" (-10) line. Always costs more when you have to do it twice. With the 5/8" (-10) return the back pressure was less than 1 psi. I don't know if the 1/2" line would have worked or not but I didn't want to chance doing the job 3 times. I use the Mallory 140 pump and the 4309 regulator. The Mallory 140 pump comes in two different configurations. If it is used with a dead head regulator it is internally by passed and set from the factory at 12 psi (not sure on pressure). If you use the by pass regulator the pump is not internally by passed. This is all explained in their istallation instructions and tech bulletins on their web site. All good reading and very imformative.

Tim C

[Formula400NYC]

Thanks for the heads up Tim. I'll be sure to check it out.