Have a cracked head, need a replacement (NOT CRACKED).
Casting number is 6272990
Apparently, these castings are really prone to cracks between the valve seats. I need them as close to stock as possible (not milled)

Let me know what you got, where you are at and how much you want.


Thanks,

Phil

philsnyder(at)mris.com

I have two set off an Hp500 stock $450.00 per set plus shipping

These are for a MK IV block, can't use heads off of a GEN 5 (or newer).

Did GM make another head similar to the 990 that would work with the MK IV block ? I ran into the same problem. I have the another engine out now, so we'll see if they are also cracked. Unless you can buy them right, you're better off buying an aftermarket set. Check ebay, but make sure they were tested.
Good luck

Yes, the 3994026 is supposed to work also.

I bought one of those, it was milled down though, came out to 110cc's my machine shop is recommending against decking the 3 other heads down at this point.


Not sure what to do, buying an aftermarket set is out of the question budget wise.

I have a couple sets of stock heads that I want to get rid of. If you are still looking give me a call. 704.293.6808 - Yankey

I have 4 990 heads and yes they crack. I have 1 good one and 3 that could be welded. All have been maged all complete one with bad exhaust valves. Let me know a fair price if you need them