I am hoping some of you guys can give me some insight into how I should set up the fuel system on a transplanted 2001 5.3 L Vortec Motor. The engine in question has been installed in a 1985 Jeep CJ7, adapted to an SM-465 transmission. I had been using the stock CJ fuel tank with a rail mounted high pressure fuel pump - 3/8" supply and 5/16" return (although this has to be reduced to 1/4" at the tank.)
I am in the process of switching to a baffled fuel tank that will use a stock Jeep YJ in-tank sending unit and pump. Will again have the 5/16" to 1/4" issue at the sending unit.
I have not been able to find answers to a couple of questions and I hope there is some expertise here I can tap into. The questions are:
1. Should I be making provisions for an evap canister or is that not necessary?
2. Should I be using a vented or unvented gas cap?
With the prior set up (unvented cap and no evap canister), the engine ran reasonably well, but once it warmed up the idle was not consistent and would vary between about 400 and 800 rpm.
Appreciate any help or thoughts you care to share. Sure there will be other information I should share, but can't think of what it is right now.