Topic: some swap questions? maybe the wrong forum...

[donut]

 

im doing a 99 4.3L swap in my YJ, and i was wondering if anyone knows if i can use an S10 or a 1500 (w/the 4.3L) fuel tank?  would anyone know if the jeep tank size and one of those tanks are around the same size?  or if i can modify the jeep tank to use the sending unit?  thanks to anyone with ideas!     

[Jeffy]

im doing a 99 4.3L swap in my YJ, and i was wondering if anyone knows if i can use an S10 or a 1500 (w/the 4.3L) fuel tank?  would anyone know if the jeep tank size and one of those tanks are around the same size?  or if i can modify the jeep tank to use the sending unit?  thanks to anyone with ideas!     

Use the Jeep's tank since a S10 or a C/K1500 tank won't even come close.  Those are side saddle tanks.  Yours is in the back and fits.  If you need more pressure disconnect the fuel pump and run an inline pump at the appropriate pressure.  It will look a lot cleaner and easier to do then try to fit a Chevy tank between the frames.

[donut]

 
well, the years S10 i have to use (smog stuff sucks!!) uses one of those complete sending unit assemblies- its pricey too.  im also doing a CJ dash conversion, is there a way to possibly combine a CJ sending unit, and a separate fuel pump (i think the S10 requires 13 psi to run) so i can get the gas gauge to work?  I was leaning towards a modified jeep tank- its just easier.  i just wanted to get the opinion of people who've been doing this longer.  thanks!

[Jeffy]

You're going to have trouble with the Gas tank sending unit.  The YJ has a 0 ohms - full and 88 ohms = empty. The CJ is the opposite, with 73 ohms at empty and 9 at full.

You can't mix sending units since they are designed for different tanks.  The mount is even different.

The years for the 4.3L to use would be late 90's stuff.  The TBI stuff isn't worth touching.  Not to mention, not Federally legal but that's another subject.  I'd rather to go with a TBI 5.7L then a older TBI 4.3L.

You can try to modify the S10 tank but I doubt it's going to be easier if at all possible.  You'd be better off getting a fuel cell and running it in the back at that point.

[chardrc]

if you where to use a tbi 4.3l (which is apparently illegal for you) you could use a sending unit/ pump form a pre 91 2.5l with tbi as they use the same fuel pressure... but i don't know much about the newer multi point 4.3l

[Rob the plumber]

The multiport injected 4.3's run about the same fuel pressure as an MPFI Jeep does. About 40 psi.