94 in an 84?

[Ghost]

Ok if I were to put a 94 YJ engine in my 84 XJ besides the fuel sending unit and fuel line for FI, and the computer and wire harness what ealse do I need to get this thing running? By the way anyone got a 4 popper computer and wire harness they dont need?

 

[Eagle]

You'll also need the '94 fuel pump. The MPI needs about 40 psi, and your '84 has a 7 psi carburetor system.

 

[Ghost]

Yea sorry that is what I meant by Sending unit. Is the Fuel pump for the 86-90 2.5L the same as the 91 and up?

 

[rixXJphx]

There's the oft-discussed front clip, with 4.0 radiator.

I *think* you're going to need the stronger tranny, TC, and rear axle that were intended for a 4.0. Plus new driveshafts f & R to connect such.
Does the '84 have the dreaded CV front knuckles, or the stronger open universals that were introduced about mid-'84?

The accessory mounts from the 4.0 are obviously necessary. I don't know how well the PS, A/C (if any) and alternator from the 2.5 will fit on the 4.0 mounts.

The 4.0 probably has a different Cat; maybe the entire 4.0 exhaust needs to come over.

 

[Ghost]

No this is a 94 2.5L I guess I let that little detail out.

 

[old88xj]

there is a 4 banger up here in VA that has problem with the intake manifold The thing has 200K on it but the body and everything looks real good on it. I was gonna get it till it turn out to be the 4 cyl. Got a nice set of wheels on it too. He wants like$700 but it has been sitting for a LONG time so i think 350-400 and it could be yours to gut and strip. If you are just looking for a new motor...

 

[Ghost]

Thanks but I guess I should say I have a 94 YJ engine coming to me. (Have not seen it yet.) And I was really looking to see if anyone has done this to an 84-85. And if anyone had the parts list around and the parts to get rid of. I have soem of the stuff to switch to TBI but did not know if there was a major change to the systems from TBI to MPI? Also could use a few images (detailed) of the engine bay and where what I need would go. I guess the air intake would have to be adressed just like the TBI swap and the windshield washer tank. Does the 94 engine have a charcoal canister and is it manditory. (No emisions laws here to say) What about fuel lines and a return line? I assume it would need all this? I finally got to realyl thinking about it today and those were some of the things I could think of. ANything else?

 

[Eagle]

Yea sorry that is what I meant by Sending unit. Is the Fuel pump for the 86-90 2.5L the same as the 91 and up?

Check the part numbers for replacements at Auto Zone's web site, or that on-line Mopar place if you can find it -- but they don't always show part numbers. The '96 thru '90 were throttle body and it was my understanding that system ran at a lower pressure, but I'm not sure about that.

 

[SeeJeepGo]

...By the way anyone got a 4 popper computer and wire harness they dont need?

I have a computer from a 92 YJ 2.5L 5sp. Make an offer - it's yours

 

[Ghost]

Thanks! I got it running but have some issues to work out. What woudl you take for it? A spare might be nice to have around if it's cheap enough.