Hello all, I had a question I hope you guys can answer for me. I just recently picked up a set of GM'S fast burn cylinder heads part #12464298 in a trade and i was wanting to put them on my 350 i have in my chevelle but gm recommends using a flat top piston with these heads for better fast burn capability and i have .100 dome keith black pistons in my car right now. Does anybody have any experience with these heads as far as would they clear a dome piston of that size? Thanks

you're going to have a lot of CR with that deal, running race gas?

I doubt a .100 dome will make a big difference as far as the burn. Also doubt anybody has done a before/after with the dome and flattop pistons and published the results so there may not be any way of knowing for sure.

On the clearance issue, I would call KB and ask them directly.

You have a 62cc chamber. Best to figure out your compression ratio before putting them on, depending on what gas you want to buy.

I'd sure check piston-to-valve clearance too.

BUT - if you've got clearance and are willing to run high-octane gas, those heads will really work for ya. I've run 'em on a few different street engines and I really like 'em. You will have to get a Vortec-style intake for them, though. The raised ports won't line up with pre-Vortec intake manifolds. I used GMPP's own aluminum 4-bbl intake with mine and I was happy with it's performance.

~Scotch~

Seems like I saw a thread on this forum about difficulty finding headers to fit Fast Burn heads and a Chevelle chassis...

Seems like I saw a thread on this forum about difficulty finding headers to fit Fast Burn heads and a Chevelle chassis...

the heads are exactly the same dimensions for headers no matter which chassis they are bolted in to.

the heads are exactly the same dimensions for headers no matter which chassis they are bolted in to.

Maybe you need to re-read my post. I'm not saying the heads are different depending on what chassis they are bolted too...I'm saying it's not clear that anyone makes a set of Chevelle headers that will accomodate the Fast Burn's raised exhaust port. If you doubt it, read this thread...

http://www.chevelles.com/forums/showthread.php?t=139082&highlight=Fast+Burn+headers

Or this one...

http://www.chevelles.com/forums/showthread.php?t=156027&highlight=Fast+Burn+headers

Or maybe the last post in this thread...

http://www.chevelles.com/forums/showthread.php?t=148912&highlight=Fast+Burn+headers

Or maybe this one...

http://www.chevelles.com/forums/showthread.php?t=133409&highlight=Fast+Burn+headers

Or consider the following quote from this thread...

http://www.chevelles.com/forums/showthread.php?t=60523&highlight=Fast+Burn+headers

"Fast Burn heads require special header flanges which I do not believe are widely available. I know that Sanderson makes them and that Cardiac was to some extent involved in Sanderson's development of these new flanges, and indeed, has their first set produced. I've heard that Hooker will produce, on a custom basis, headers that work with Fast Burn heads and there are probably other header manufacturers that can make them, as well. But they are NOT a standard production item for anyone except Sanderson, as far as I know."

Hooker makes some:
http://www.jegs.com/webapp/wcs/stores/servlet/KeywordSearchCmd?storeId=10001&catalogId=10002&langId=-1&N=0&Ntt=FAST+BURN&Ntk=all&Nty=1&D=FAST+BURN&Ntx=mode%2Bmatchall&Dx=mode%2Bmatchall&searchTerm=FAST+BURN

I didn't read the text, but they have 4 listings searched by "fast burn" in Jegs.

hooker 2116 in a 68 chevelle no air conditioning

Fast burn heads have the raised d shaped exhaust ports. Regular 1 3/4" headers are large enough that the exhaust ports will not be blocked. These are are what scoggin-dickey chev and others recommend using. I have hooker super comp 1 3/4" on my fast burn heads, using the raised port (LT1 i believe) header gaskets.

Hedman makes a complete line of hedders for fastburn and LT1 exhaust flanges. hell, even Vortec heads have a slightly raised exhaust roof, and i had 2 sets of standard headers on that with no issues- Dynomax and Hedman.

well, as far as octane level goes, im already running about a 62cc chamber (heads have been milled down) on a set of sportsman 2's on the car right now. just looking to pick up a little more horsepower with the better flowing heads. I called up chevy to try to find out if a done piston would work but haven't had a chance to call up kb though. thanks guys