Are these any good for performance?
Are they indeed closed chamber?
Would I need new pistons? (mine are advertised as 0.230 dome top piston with 2-valve reliefs. 10.32 Comp. Ratio with 106.9cc Head)
Would they bolt on a MKIV block (flat tappet cam) without having to change anything ?
Estimate on a fair price for a complete used set?

I have never looked into later model BBC's so I am clueless about them other than they have roller cams and no fuel pump boss. :(

there are bbc vortec heads?

well like I said, I am pretty clueless when it comes to late model BBC stuff.

I thought that they existed for both big and small block. That's what the set (I found) is advertized as. I should have used a different title. Nobody has said boo on this topic until you came along. Might repost unless I get some feedback on these.

got a link for the ad?...used or new? if new, i would think the seller would best know the applications and other parts needed (though i wouldn't bet the farm on it) if its a private seller or an e-bay type thing, your guess's are maybe better than theirs. i'd try the "engine" section and describe them and your current parts carefully (pics would help) some of these guys can tell you exactly what you have just from a pic of the chamber and/or ports.

They are the common peanut port heads that have been used on all late model BBC engines. Do a search, lots of topics on this. I could very well be wrong about that but post the casting numbers to be sure. Peanut port heads are worthless for a performance application.

Ive heard and read several reports about these and all have said that they flow well and are similiar to some of the old IV heads. Get the #'s and look them up on Mortec.com. The Vortec 454's are different than some of the regular 454 motors. Ive got one also, complete w/ the fuel injection. Hopefully, it'll be in a 71 ht one day.
Rick

thats a cool site, thx for the link rick.