Differences between '01 XJ and '99 XJ

Just a hypothetical question.

IF I had a 2001 XJ 4.0lL, Auto and a 1999 XJ 4.7L Stroker, Auto and wanted to swap the motors between the 2 vehicles what problems would I encounter with the changes in model years. I "think" that the underhood harness' would be the only difference between the 2 models. The '99 still uses a distributor and one CAT and long tube headers, where the '01 uses the distributorless ignition with coil packs and warm up cats on a two piece header.

Are the CPUs different OR could I simply swap the underhood harness from one vehicle to the other?

What else am I missing?

Just kicking around some ideas as my wife and I are planning to have kids soon, God willing, and would need a vehicle with more room than the MJ has but I would like to keep my Stroker if possible.

You converted your MJ to all 99 engine management, right? Seem to remember some of your posts before.

So you are wanting to put the 99 stroker into the 2001, right? Just swapping the longblocks would be simple, change the stroker to distributorless ignition. You could have registration/emission issues in your state.

You might get better responses in Mod tech.

joe_peters said:

You converted your MJ to all 99 engine management, right? Seem to remember some of your posts before.

So you are wanting to put the 99 stroker into the 2001, right? Just swapping the longblocks would be simple, change the stroker to distributorless ignition. You could have registration/emission issues in your state.

You might get better responses in Mod tech.

Click to expand...

You are correct, the stroker in my MJ is running all 99 engine management. Thinking ahead I may want to pick up a 2000/2001 XJ and keep the stroker by putting it into the XJ.

Aren't the wiring harnesses different between the 2 due to the distributorless and more o2 sensors on the 2001 or am I missing something?

I'm in NC so no registration issues.

Yeah, there will be differences, but if you swap just the long blocks, keep the sensors/exhaust (intake shouldn't be different) then you will have your stroker with a distributorless ignition and all the appropriate engine management in the XJ, drop the 4.0 longblock in the MJ and run it with the stroker's distributor and engine management/exhaust.

Should work just fine.

joe_peters said:

Yeah, there will be differences, but if you swap just the long blocks, keep the sensors/exhaust (intake shouldn't be different) then you will have your stroker with a distributorless ignition and all the appropriate engine management in the XJ, drop the 4.0 longblock in the MJ and run it with the stroker's distributor and engine management/exhaust.

Should work just fine.

Click to expand...

That's the answer I was looking for. Thanks

You still cant legally do it!

RCP Phx said:

You still cant legally do it!

Click to expand...

IF he is just changing the long blocks--keeping the 01 exhaust/engine management, then there is NO legal issue.

IF he was using the 99 exhaust/engine management in the 01, then yes, legal/registration issues.