I have a question? Ihave double humped heads on my 68 chevelle ,its a s/b.350. the casting number on the heads are 8927186.I was told these were 202 heads.could someone tell me if these are 202's or what size valves& chambers these heads have.


thanks ,sasquatch58

They could be either way. You can`t tell by the casting numbers. If they have pressed in studs, most likely they are 1.94 heads unless someone went through them and installed the bigger valves. If I remember right, factory 2.02 heads had screw in studs although they could be added at any time also. The best way to tell is to yank them and see what they are.

If they indeed are 3927186 and have a date code of '68-'71, which they probably will, they're shown to be 2.02 and 1.60 valves. The "441" heads are "1.94" heads for those years. One reference is http://www.67camaros.com/bynumbers/heads.htm I too have heard of smaller valves in these castings but have never actually seen any other than 2.02's in them.

I had 2 sets of 186 heads that were 1.94 valves. At the time I did`nt know anything about them except that they were camel hump heads. The 441 heads that d1 is refering to are also a open chamber head, the 186 are closed chamber. If your looking to rebuild them, there are cheaper, better heads out there. The fuelie heads are old tech. The late model vortec heads are better and cheaper.

186's came in both configurations. chambers were 64ccs. seats were soft of course. they will flow well especially with some work. they are good street heads esp if they are already paid for and are correct for your car.