Sorry, just food for thought is all. Back in the day, they used to spin these little class required size limited, short-stroked BBC engines up around 9 to10,000 rpm if not mistaken.prairiehotrodder wrote:How did we get on to the topic of building a smaller motor? Thats not happening.
Need more compression, then hunt up a pair of old -206 heads and work them over.
They are large oval, 96.7 to 98 cc, bathtub, true closed chamber heads. I have a pair out in my garage! And they will breath just fine up to like 5,000/5,500 rpm or so! I bought them to play with a P/U 454" work-truck engine that is usually about 7.9 CR or so. I figure with the .020" thick steel shims, I could get it up to like 9.3 or so CR and not change the stock dished 454" pistons. Just a head change is all....
And there are the old, "smog", heads that are square-cut from the intake valve to the exhaust valve with the open chamber quench removed that are large oval that are down around 113 or so cc's. I read where they work a lot better than most would think because the exhaust valve quench is gone! BUT you have to CC these because they can vary a lot chamber volume-wise.... Like from 120 or so down to 112 cc's.... -818, -148, and -292 heads if not mistaken.
The late, great JL said that properly prepped large oval heads will support up to a mild 540 engine! And do dandy on the 496"/502" engines.
Years ago, JL did two mag. articles, One on the 496" and the other on the 502"! I want to say that the 496" engine got up to above 600hp with CC's great old 288AR solid street roller, but it's been years since I read both articles.