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Gen VI head swap

728 Views 1 Reply 2 Participants Last post by  Schurkey
Looking to bump performance up a few notches by ditching the L29 vortec heads and going with some older closed chamber ovals. I do not want to open up the bottom end since it is fairly low miles and runs solid as is. My budget is $1000 total expenditure.

My understanding after a few searches is that I can run Mark IV heads on my Gen VI block with head gaskets that match the heads. Is there anything else I need to be aware of. I know I will need different rocker arms, but what about push rods?

For heads, I have found a set of bare 290 castings but I think the guy wants too much for them... $250. By the time I buy valves, springs, keeper and locks and the required machine work I'm guessing it would cost over $1000, which kills my budget

Another option I've found is a set of 390 heads that have already been built up with 2.19/1.88 vales and some 'mild' porting for $550. I would still need to get a set of springs to match my HR cam, but these seem to be the better buy.

Advice and opinions welcome.
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I've never put older heads on the newer blocks--but--I'd have expected you need head gaskets to match the BLOCK, not the HEADS.

That's how it is when putting Vortec heads on the MK IV block, anyway.

Pushrods are the last thing you buy to complete a long block. Everything else has an effect on pushrod length--block machining, head machining, cam choice, head gasket choice--etc.
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