302 Swirl port heads

[TeddyG]

I've read about these heads that will improve performance on my 73 Scamp 318. I also read on a message board somewhere that I could get these heads new or rebuilt with the 1.88 and 1.60 valves. I can't find the post and was wonerning if someone knows where I can get these heads. People have told me that these heads are plentiful in the junk yards, but I have been to every junk yard around here. Whenever I ask about these heads they look at me like I am crazy, so I'll just pay more for a rebuilt set if I can find them. Thanks.

[DartGT66]

They were used in the late 80's 318's, a couple of years before the 'magnum' engine came out. You must search for the casting number, the three last digits of it are '302'. I have heard that some of these do not have the casting number on the intake poerts like in the older heads, but only on the deck surface. So, if you find a late 80's car or truck with heads that have no cating number under the five bolt valve covers, you may be at the right track. If you remove the heads, you can recognize them from the closed, kidney shaped, combustion chambers. These heads have 1.78/1.50 valves stock, and to get good performance out of them you have to change to 1.88/1.60 valves and port the bowls. Leave the valves as high to the surface as you can to reduce the combustion chamber size and raise the stock CR a little. And use thin head gaskets too, you can't get too much CR out of a stock piston 318.

[CudaMike]

They are supposed to be on 85-87 and maybe later years too. They are on 318 2 barrel roller cam engines. I may be wrong on this one but I thought 302's had the casting number on top of the ports but the 308's were the ones with the casting number on the deck side. Anyway, I'm looking for a set of 302's myself! Good luck.
P.S. - Casting number 646 is also supposed to be a 318 swirl port head according to Hughes. Don't know the years.

[DartGT66]

You could be right about the castoing numbers, I have not even seen 302 heads, and have had the 308's in the early 90's but do not remember the number locations. I think it's the throttlebody equipped engines that are the most evident engines to have these highswirl heads. by the way, I replaced a set of pocket ported 2.02/1.60 '915' heads with the out of the box 1.88/1.60 '308' heads in a 360 and found a very noticable performance increase.