Head upgrade??

[torchroadster]

I've got water in the #3 cylinder of my '93 4.0L - so I'm in the middle of tearing it down and thinking ahead (no pun) a little bit. Assuming I find a cracked head I'll need to replace - why not upgrade a bit? I've searched around for 4.0L performance heads and come up blank. Are there any aftermarket performance heads? This is a daily driver so nothing too radical or too expensive but wanted to check into my options.

While I've got the heads off what else should I replace? Lifters, pushrods, rockers, etc.??? Don't have any experience with this motor so I'm not sure what the weak points are - other than the head castings!

 

[Minivek]

Try doing a search on this site:
http://www.moranav6racing.com/category.html?CategoryID=32

But other than having stock heads ported, it gets expensive real quick...

 

[TennTechMan]

Awesome find! If only had an endless supply of money. I didn't reallize there was anyone making that many internal parts for the OHV engine.

There are some less expensive things that could be done. You could just put later model heads on your motor to bump up the compression, but I'm not sure how much improvement you would get with that as an only modification. I'd recommend at least upgrading the cam also. Check out Craeger's thread at the top of the Modified 91-94 Forum page. I also have a thread going about my engine build which includes the 95TM heads.

 

[torchroadster]

Thanks guys that's helpful. I'm not pulling the motor, so the cam is out of the picture. Tonight I got the heads off and it looks like a head gasket not a cracked head so I may get off cheap.

What else while I"m in there? lifters? pushrods? etc.

 

[TennTechMan]

If your lifters have been tapping extremely loud, you may want to look at changing them. Due to their expense, I would just keep the old ones if they are working well. Check the pushrods to make sure they're not bent. If you've overheated the motor much, you may want to consider having the heads checked for cracks. It's good insurance even if you haven't overheated the truck.

 

[torchroadster]

You can see the pictures here:

http://www.explorerforum.com/forums/showthread.php?t=189302


Wow I just checked the price on lifters and I see what you mean - my old ones weren't making any noise so they are staying put. I'll check the pushrods real close and replace the valve stem seals.

I'm going to have the head checked that leaked for sure and maybe the other one too - need to take a look at it once I have it off. At the least I'll probably have the side that leaked resurfaced to make sure it's flat.