I just picked up a set of 781 BBC heads oval port, are these heads any good? What cars did these come on ?

www.mortec.com (http://www.mortec.com)

They used them on cars and trucks....lots of them http://www.nastyz28.com/ubb/smile.gif

according to mortec.com:

336781.....73-85...oval...OPEN...454, 118cc chamber, 256/114cc ports

Thanks for the help guys

781's are one of the best flowing oval ports made. There are several versions, so the only way you will know the chamber size is to CC them.

Just match piston dome shape and quench distance and headgasket thickness such that you create the CR. you want is all.

I use the ROSS Racing Pistons CR. Calculating site.

I use a stock piston down in the hole of .025". Then try to shoot for about 9.5 to a schosh under 10 to 1 CR., (depending on the intake valve closing point for a good Eff/Dynamic CR. of about 8 to 1), and a from .035" to .045" quench distance.

Hope this helps..

pdq67