4.0 head conversion

[DOUBLEC]

For obvious reasons I'm doing a 4.0 MPI head conversion on my 1977 CJ7. The doner was from a 1991 XJ. The fuel rail supply and return are 5/16 tubing from the 4.0. The stock fuel sender is 5/16 supply and 1/4 return.

Has anyone out there done this conversion on a CJ. My concern is too much return pressure.

 

[superj]

I would imGine your regulator will handle it but if your worried run a new return

 

[DOUBLEC]

I intend to, but I'm limited to a 1/4 inch at the gas tank fuel sender. No matter what I do I'm stuck with 1/4. This is a budget conversion, don't want to add any extra money in this, especially a in tank fuel pump. Looking for someone thats done this conversion on a early CJ7.

Thx

By the way, I have a detailed list of the ECU / wiring harness / power distrubution by pin # and wire color code if any needs it for a 91-96 XJ 4.0 conversion, way better than any manual. It was a long winter searching for parts. I'll provide it as soon as I start the motor.

 

[superj]

sweet!! i keep thinking how much i would rather go fuel injection too. as much as i love carbs, you cannot beat FI. they are only 1/16 difference, what pressure does the fuel injected pump run at in the upper and lower limits or acceptability? what does the regulator hold it at? it is probably fine but its good things to consider

 

[jps4jeep]

I wouldn't be overly concerned.. I will check mine when I get home, but ther eis probably a reducer to maintain some return line pressure.. that line should not have a whole lot of pressure to begin with.