Best 4.0 Block Candidate for a Stroker

[yj93ben]

I'm sure this has been addressed, here. But really couldn't find an answer. What is the best block, by casting number, to build a 4.6/4.7 stroker? I'm starting my second build. Gathering parts and pieces now. My last build was on a 53010449AA. I've heard good things about the 53020569. What's everyone's thoughts?

[Muad'Dib]

Did you see the FAQ by chance?

viewtopic.php?t=52

[Cheromaniac]

Any 4.0 block from '87-'06 will do, though '96+ NVH blocks are slightly better. However you also need to know which Jeep model the block came from because the engine mount bracket bosses may be in a different position.

[Russ Pottenger]

Any 4.0 block from '87-'06 will do, though '96+ NVH blocks are slightly better. However you also need to know which Jeep model the block came from because the engine mount bracket bosses may be in a different position.

X-2

I’ve heard of customer stories where they’ve had a completely machined block and engine partially assembled before they realized that engine mounts and bracket mounting holes were significantly different and they decided to start over and had to source another block.

Just to be safe I would highly recommend building a donor engine with the same block casting number that is currently in your Jeep.

[Cheromaniac]

I used a block from an '00 XJ for my stroker build.

[75SV!]

Here's my knowledge of the 4.0L blocks.
87-90 is the RENIX. It is a bit more solid. I remember there being a US and Mexico cast blocks. I remember the Mexico blocks as having 2 oil pan rails or such. They are suppose to have higher nickel content, thus a bit stronger. The heads are a bit different in the intake port. Also, the main bearing are different. They are 232 and 258 type. The tab on them is located different than the 4.0L
91-95: HO. The block was lightened. Head revised.
96-98 : Block revised. Webbing around the cylinders. Added a main cap girdle. Also, dowel pins locating the cylinder head. A bit revised head, but near the same flow as the HO heads.
99: Oh, the fun begins. The WJ block and heads changed. See below. For the XJ and TJ (I think) a thrust plate was added for the camshaft.
2000: Even more fun. The TJ block is now like the WJ block. The XJ had heads revised with smaller exhaust ports. Some have had issues with those heads cracking. I have seen two of them. My 2000 XJ has 280K on it. Heads fine. I don't know if it was replaced or not. There were FED and Cali models.
2001: XJ block and head same as the 2000. All are Cali emission rated.
2003: TUPY head. Revised and cast in Brazil. Prevents cracking around the 3&4 exhaust ports.
OK, the WJ blocks and 2000+ TJs. Basically, has the same features as the 99+ XJ blocks. The motor mount bosses are drilled different. One is longer on one side and shorter on the other. The Accessory drive was changed. The bosses ect. are there. Many are not drilled. Brown Dog does make motor mounts to adapt to an XJ. I did start to do this. I put on an HO head. This messed up using the WJ accessory drive. There is a thread hole on the front left.
I used a 2000 or 2001 for a stroker and a '99 for my mini stroker. I had a cam ground for the mini. Its been about 5 years ago, that cams for the 99+ blocks have been available.

[LJBean]

Here is a source of block interchangeability:

https://wranglertjforum.com/threads/4-0 ... ity.16801/