mpk490p

is anyone using the 4309 with return line on stock fuel lines?
i read somewhere that you are suppose to have the same size lines for feed and return?
thanks
Mark

trochoid

iTrader: (6)

Fuel line size depends more on what size pump you run. The Mallory Comp 140 gph pump requires a minimum of 3/8" supply and return lines when used with their 4309 return style fpr. Unless you're going with boost, the Comp 70 pump is large enough for any rotary carb.

mpk490p

i already have a facet red top pump that i will be using, so you are saying it depends more on the pump than the regualtor?

trochoid

iTrader: (6)

Yes, the more volume/gph that the pump flows, the larger fuel line needed. The 4309 will work with anything from a low pressure 70 gph pump to a high pressure 255 lph pump. Odd thing is the SE fuel lines are larger than the 2nd gen lines, which fall midway between the SE lines and the 12A lines. But then the SE pump puts out more volume than even the TII pump.

680RWHP12A

stock fuel lines will be fine

mpk490p

Thanks the shell is a GSL-SE for reference

Mark

trochoid

iTrader: (6)

Good to go then.

mpk490p

i have since put a mallory 4110 pump on and i can't get the pressure up past 2 it's making the car run bad on idle do you thing the return is now a issue? usinf a 4309 set up was fine on my old pump, i'm also running a stock filterbefore the pump which i will chance to a metal FI one as it looks like it has sucked itself inside out!