1999 engine block

Please forgive my ignorant self it was easy to search, guess I dont know the key phrases.
I have a Jan 99 4.0 I want to put in a 90 XJ. Just curious if it will work? I realize I will likely have to use the 90 intake and such.

I have 337K and trying to have a back up laying around

thanks in advance
Kerry

Since the '99 is a newer HO motor with distributorless ignition and the '90 is a Renix motor with a distributor I believe some accessory mounts/brackets and the engine bosses may differ slightly....
Someone correct me if I am wrong......

99 doesn't have DIS iirc... but otherwise correct. Some minor stuff may be different. There might be head port shape differences, I don't remember what you do about that, one of the RENIX guys should know more.

Early 99's do have a distributor. Mine does. When the cutoff is I don't know, but it's easy enough to look.

You may have to fudge the knock sensor mounting if you put Renix stuff on a later block, and you'll have to remember to use the Renix flywheel because the crank position notches are different. There may be some other sensor issues, such as the location of the temp sender, but I'm not sure. The 99 has a different belt routing and power steering pump, etc., but I don't think that should be a problem.

Missed the word JAN.....
The '99s that I have seen didn't have a distributor so they must have been the ones towards the end of the '99 model year.

I believe the entire '99 production had distributors. There's no switch-over to the 2000 configuration shown in the '99 parts catalog.

Correct the 99's dont have the distributor. The 2000's started that change best I could tell, sure its possible the later 99s may have. Looking at moveing all accesories over to the 99 block. Im sure something will need modifiing bracket wise

I gather later 99's have the later head that is designed to accommodate the multi-coil version, but never checked whether any actually used it before 2000.