double hump heads? question??
 

Would stock double hump heads hold to 12.5:1 compression?

Well with new springs to match the cam and grinding the valves!

define, "will it hold"

my 355 is 12:1. double humps hold pretty good. had to put hardened seats and bigger springs on them.

What the hell does it mean when you say a head "holds" :?

as far as DOUBLE HUMPS GO,UNLESS YOU GET THEM CHEAP AND THEY NEED nothing I wouldn't bother...you will sink a bunch of money in them and still have a sub par head. If they are good and cheap/free then I'd use em if I were you since I know your budget is tight.

jmo

I've ran the 492's with 14 1/2 to 1 compression on gas 20/25 yrs ago, the set i had was roll milled to increase the compression, had them flowing in the 270's in. and 73% on the ex. In fact they ran as good as a set of fully ported Brodix 10's i had. I ran both sets on a 358" and a 406" motors.

Zip.