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Old 10-02-2011, 06:43 PM   #122
68Gold/white
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Join Date: Sep 2011
Location: Ark City, Kansas
Posts: 3,265
Re: 1969 C10 SWB Stepside - Big Block project

Quote:
Originally Posted by CC69Rat View Post
I'm probably going to stay with the iron heads. To be perfectly honest I'm not what I'd call familiar with the heads either. From the research I have done though, they didn't come on this motor, and were originally a decent head of some sort. From what I understand they are closed-chamber oval-port head known to have issues with the valves being a little small. I am looking to be sure but I hear 2.19/1.88 really help on the bottom end. While I have it apart I might just flow these a little and go with larger valves (unless they already have them, which is possible) ..

.. just my thoughts right now. Could change.
It's not easy to always know what type of head is which. Most oval port 454 heads that I know of are open chamber. The ones I ws told to use by my builder friend, years ago are open chamber, but the small open chamber. If I remember correctly, the chamber is somewhat triangular shaped. The larger open chamber heads are similar, but just have larger chambers. You want to stay from too high compression, as you want to stay from too low compression.

Have any pic's of the head???

In my opinion, you're going the right direction. As a general rule of thumb, you want an aluminum head engine to have a comp ratio approximately one point higher than an iron head engine. Iron retains heat much better than aluminum, making an aluminum head selection for a 396 even more difficult.
Can't wait to see, the result!!!

Bigger valves in a smaller port engine is a good thing. BUT, even an oval port BB Chevy is not really a small port.
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