The 2 pair that I have are ported and gasket matched. They are unassembled, but I have all the parts, including all the inconel exhaust valves. Let me verify the casting numbers tonight.

I have 2 sets of HP 500 gen 6 heads with 165 hours on them. No cracks if you are interested.

Yeah, they're definately 990's.

What are a pair of cracked 990's that are port matched worth?
What about the one that's not cracked?

ScarabScoundroul
i end up with four out of eight heads being good so i am set but thanks for the help.

Well that's good. So what is 1 good 990 head worth?

FYI the 990 castings have cast in valve seats and the 188 casting have pressed ln valve seats.The problem is that if the 990 heads need seats when the try to cut them out 9 times out of 10 you hit a water jacket.So in my opinion the 188's are better than the 990's for the simple fact that they are easier to rebuild.

I don't need a match. I replaced my heads last year. I'm only asking because someone else has found my head as a match to thiers. So I was wondering what I should sell it for. I had a friend that feels it's worth $300. ? ? ?

I have 1 990 head that is decent. Not rotted out , not ported, but needs rebuild. Make offer. Just threw four on the scrap pile Just went for New Dart. Beware of used dart heads. Early castings did not have the cast in struts where they eliminated the exhaust crossover, and are prone to cracking. Dart heads are cnc ported. They are heavy too. Really thick decks, etc... I couldn't believe the difference when I went to pick one up. BBB

BBB, what's it worth to you?