sundy58

I have chased problems around on my 90 XJ. I finally got the idle normal and things seemed to be OK for a time, now I get 8 miles to the gallon. I have new injectors everything else is old. What is involved in changing to 4.0L and transmission with no computers? This is my weekend beach runner so I just want something easier to work on.

dave1123

EASIEST way is a 4.0 with breaker-point ignition, a carburetor, and an AX15 trans. Properly tuned, you should get up to 16 mpg or better with a carb. You'll probably need to buy or build an intake manifold to mount a big enough carb though. I think a 4 liter needs at least 2 barrels.

sundy58

So just disconnect the computers, replace the distributor, not hard, changing from an automatic (sorry I left that out) to manual not so easy. I guess with a hydraulic clutch it wouldn't be that bad.

Anybody have links to threads where others have done the no computer conversion?

dave1123

Don't forget to reduce the fuel pressure! A carb only needs about 7 psi. You COULD keep the injectors with a stand-alone controller, but you wanted NO computers.

sundy58

Well some day I might learn. I decided to an ignition tune up and when I pulled the cap off the center contact was missing, gone, disappeared. I replaced the cap and rotor and she' running the best in years. Note to self, check the basics first!

fb97xj1

How was it even running without that?

dave1123

Massively hot spark!

sundy58

Not well, not well at all.