Replacing my 258 head with a 4.0 head

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   Oh, no, I never reuse gaskets. I was just pointing out the head gasket's condition. Head bolts look like replacements. Probably Fel-pro units as they had the pink-ish lube on the threads that I've seen Fel-pro bolts have, with the exception of the driver's front bolt; which had white sealant on it for the water jacket it goes into. If the manufacturer's service procedure doesn't specify to replace the head bolts, I reuse them. Most all of today's engines use torque to tell bolts, and cannot be reused.

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232jav3sp Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jan/09/2013 Location: Texas Status: Offline Points: 2451	Post Options Post Reply Quote 232jav3sp Report Post Thanks(0) Quote Reply Posted: Jul/18/2021 at 9:17am
	Oh, no, I never reuse gaskets. I was just pointing out the head gasket's condition. Head bolts look like replacements. Probably Fel-pro units as they had the pink-ish lube on the threads that I've seen Fel-pro bolts have, with the exception of the driver's front bolt; which had white sealant on it for the water jacket it goes into. If the manufacturer's service procedure doesn't specify to replace the head bolts, I reuse them. Most all of today's engines use torque to tell bolts, and cannot be reused.

Pdok Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Apr/03/2011 Location: Alabama Status: Offline Points: 1025	Post Options Post Reply Quote Pdok Report Post Thanks(0) Quote Reply Posted: Jul/18/2021 at 4:16pm
	Mopar P4529242 is a fairly thin gasket, if you're wanting a smidge more CR. Consider port-matching the intake/exhaust, too. I decked my 7120 .040, too. I'm not entirely sure, but I think the TUPY head was later, like after 02? If you got the header from that, does it match up with the 7120? I'm not sure if the intake ports from that head would match the 7120? I never tried that combo, since I got them both from the same donor.
	76 Grem X 258/904,4.0 head/MPFI, Comp X250H cam, Hughes springs, Clifford header, serpentine swap.

232jav3sp Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jan/09/2013 Location: Texas Status: Offline Points: 2451	Post Options Post Reply Quote 232jav3sp Report Post Thanks(0) Quote Reply Posted: Jul/18/2021 at 5:01pm
	MOPAR P4529242 has been discontinued. The TUPY head was the last iteration made and used split cast iron manifolds with cats bolted to them. I plan to use this head on the 232 in my Rambler, and use the 7120 for a stroker build.

Pdok Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Apr/03/2011 Location: Alabama Status: Offline Points: 1025	Post Options Post Reply Quote Pdok Report Post Thanks(0) Quote Reply Posted: Jul/18/2021 at 8:24pm
	Dang, it sure has. Guess it's been longer than I thought since mine. Welp, plenty of other options exist. Did not know that about the TUPY heads, sounds like you've got a plan already then.
	76 Grem X 258/904,4.0 head/MPFI, Comp X250H cam, Hughes springs, Clifford header, serpentine swap.

232jav3sp Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jan/09/2013 Location: Texas Status: Offline Points: 2451	Post Options Post Reply Quote 232jav3sp Report Post Thanks(0) Quote Reply Posted: Jul/18/2021 at 9:15pm
	I almost grabbed the manifolds to do a custom dual exhaust, but I have another early header, and obviously it will make more power. Pretty sure the TUPY had was to correct the very crack prone 0631. Newcomer racing made good power numbers with one. The TUPY signs off earlier then the older heads, and is why I will use it on my Rambler. Perfect cruiser/street head.

farna Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Moderator Lost Dealership Project Joined: Jul/08/2007 Location: South Carolina Status: Offline Points: 19676	Post Options Post Reply Quote farna Report Post Thanks(0) Quote Reply Posted: Jul/19/2021 at 6:57am
	Correct on the TUPY head. The early 0631 casting doesn't have it and is prone to cracking IF the cooling system is neglected at all. I've seen 100K Jeeps with the early head and no cracks, others with cracks with as few as 35K miles. Most seem to crack in the 50-70K mile range. That must be when the factory coolant starts to "wear out" or get thinned out due to adding water (just a guess). In general, take care of it and don't run it real hard and it won't crack. That would be 2000- mid/2001. Late 2001 models usually have the fixed (TUPY) heads. If running a 4.0L head on an early 232 you will need shorter pushrods. I recall a fellow telling me that Ford 351 pushrods were the right length, but I don't recall if he used Windsor (I suspect... that's the small block version, right?) or Cleveland pushrods.
	Frank Swygert

232jav3sp Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jan/09/2013 Location: Texas Status: Offline Points: 2451	Post Options Post Reply Quote 232jav3sp Report Post Thanks(0) Quote Reply Posted: Jul/19/2021 at 8:59am
	I have a 199 on the floor, right now. Head is off and number 1 is frozen at TDC ( +/- a couple thou). I plan to use it for mock-up so I can measure for pushrods and I want to cc everything so I can determine what my compression ratio will be. Very curious to see how true the factory 8.5:1 rating is. Piston volume and CID aside (199 flat top, 232 dish) everything else is the same, and both have the same comp rating. I ought to at least get a good idea for my 232 w/4L head will be. According to Wallace Racing's compression ratio calculator, my car's cranking compression and cam specs indicate 7.6:1. That thicker aftermarket head gasket really hurts things. Also, I made a mistake... It's casting number 0631 that were crack prone.

farna Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Moderator Lost Dealership Project Joined: Jul/08/2007 Location: South Carolina Status: Offline Points: 19676	Post Options Post Reply Quote farna Report Post Thanks(0) Quote Reply Posted: Jul/20/2021 at 6:59am
	Only EARLY 0631 castings (late 99-early 2001 -- by the engine date code, 2000-mid 2001 Jeep model years) are crack prone. The TUPY head is a 0631 casting, but has TUPY cast in the upper side between #3 and #4 cylinders (between the valves for those two cylinders).
	Frank Swygert