Hey guys,

2000 XJ (313 head)
250K miles

My 331 head appears to be shot/cracked/busted/wore out/kaput ....

Can I use a 630 head in place of the 331? Everything I read is that the only difference between the two is the coil rail mounting bosses.

Seems like there isn't a 331 head to be found.

Chap

 

I'm going through the same thing right now. I have no idea how long it's been cracked as I just got the Jeep a couple months ago. It has 184k miles on it.

Anyways... you can put on a head stamped with 0630 or 7120. If you do, you will need an adapter plate for the exhaust manifold. The exhaust ports got smaller for emissions... heats up faster.

7120 had the largest exhaust port ('91-'95)
0630 was a little smaller ('96-'00)
0331 has the smallest exhaust port ('99-'06)

Here's the link to the guy on NAXJA who makes the adapter plate.
http://www.naxja.org/forum/showthread.php?t=919384

I just contacted him on Friday. He emailed me back within a few hours, I sent the money via PayPal and he shipped it Saturday.

Also, like you said... you will need to fab up some brackets for the coil pack. Easy peasy.

Now, if you can find a head from a Grand Cherokee from late '02 to '06 it should have the words "TUPY" stamped on the head... you should be able to see it if you look under the oil fill cap. Then it will just pop right in... no adapter plate... no fabbing up brackets for the coil pack.

 

I went all out and bought a new head with new valves valve guides and Springs from clearwater cylinder heads in fl. It was it was pricey but it was worth a piece of mind 5 year unlimited mile warranty for 455.00 shipped to my door

 

I was going to do the same... but my dad had an engine laying around that he was going to use to build a stroker. He said he's never going to get around to doing it and said I could have it. The price was right... Free. The engine has 100k on it. And after taking the valve cover off and seeing this on my Jeep:



I decided to just pull the engine and drop in the one with from my dad. All the bearings are more than likely shot on mine anyway. Going to check clearances and probably put new rings on the one going in.

The previous owner had put in Stop-Leak. I can tell because the engine compartment is "glittery" from the coolant leak. And they probably didn't change the oil as often as they should. So, cracked head means there is a nice slurry of coolant, oil and stop-leak... everywhere.

 

chap, u can use the heads that Jeepasaurus9 said but u dont have to get an adapter plate.
just get the exhaust man. with the head u get.

 

They changed the exhaust manifold in 2000 to comply with emissions. I was going to do something similar. My dad suggested getting a header for a little more then the cost of the adapter. I'm thinking... good idea. But a header for a 2000 and 2001 Jeep Cherokee is around $400 and the only two I found were the ones from SeriousOffroad.

http://www.seriousoffroadproducts.co...DGE-00-06-4.0L

http://www.seriousoffroadproducts.co...SHED-STAINLESS

They changed to a "Y" pipe. So... the manifold has two flanges that connect to the down pipe. There are two pre-cat's... with an oxygen sensor on each. I think there is a total of 3 oxygen sensors.

Here's a header that will fit a '91 to '98... notice it is only a single flange and much cheaper.
http://www.seriousoffroadproducts.co...NIFOLD-GASKETS

Here's a link to where I got the majority of my info...
https://www.cherokeeforum.com/f67/20...pgrade-165130/