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Old 10-14-2012, 11:14 AM
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Originally Posted by OMARS67 View Post
so is it safe to say that if the 049 and my 148 were cc close and both had 2.19 vavles they would produce close to the same power. thank for the response guys.
Mortec has the following info on the c/n 148 BBC head:

3933148....'69-'84; oval port; 112cc open chamber; '69 396/265hp, 366T, 427T

Your 148 heads are more like the c/n 215 heads as far as the chamber volume goes. They're sometimes called "semi-open" chambers and should be about 110-112cc.

If the CR was the same there wouldn't be much difference in performance between the two heads. Getting compression is easier w/the smaller chambers especially if building a small BBC (396/402). In a 454 engine, watch that the compression isn't too high.

Fitting larger exhaust valves in the semi open chamber requires some finesse to minimize shrouding.

BTW, if you look at the info at the nastyz28 site, it shows:

3933148- 1969; 366/396; 122.1cc open chamber; 2V/427 265HP car & truck

The nastyz28 chamber volume is a typo.
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