Little help?

Ok, my 90 XJ's 4.0 is pretty shot, lots of bearing noise and blowby. I have a 258 from a '76 J10 that ran great when it was pulled. I would like to swap the head over to the 258 for a really cheap swap, but I've heard conflicting statements about it. Some say it'll bolt right up, others say water jackets won't line up correctly. I am more than wiling to search this, but when I type "258 block and 4.0 head" the 258 and 4.0 are too short to yeild any results. How can I effectively search this out here to get the answers I need?

Since the 4.0 of yours needs a rebuild anyway, why not just keep the 4.0 head? The 4.0 is more powerful than the 258 anyway. The intake and exhaust manifolds from the 4.0/258 certainly do not swap, so you cannot put the throttle body on the 258 intake.

Why not also get the crank and rods from the 258 and do a stroker.

I want to do the stroker, but right now I have zero dollars for the required injectors and camshaft and I'm not sure how much longer the 4.0 will stay together. What I want to do is swap the entire 4.0 cylinder head onto the 258 block, not just the intake/exhaust.

Hmm...I am in the same boat.

I still think that you would be better off keeping the 4.0 you have. You can basically "almost" rebuild the thing with it in the truck. Pull the oil pan, pull the crank, pull the head and lift the pistons out. Hone the cylinders, slap new rings on the pistons, new bearings in the bottom end and rods and put it back together. Should give you another 80,000 miles at least?

I would think this, if done yourself, would cost less than all the swapping and trouble of trying to make a hybrid motor work.