You could run those on a 327 if you wanted, would it work good, maybe, maybe not. "street" is relative these days. I know guys that run darn near pro-stock engines on the street, is that samrt, not really, but they do it. With that said, on a 406, that really isn't that big a head. If you have any cam in it, they will work good. The one thing I notice a lot of guys talk about, is tq on the street, and its king. Well, if you think about it, if you have a serious car, and, heavens to bid, street race, the guys that do well, are the ones that hook. Hooking on the street is pretty hard to do. So, you build an engine thats soft on the bottom, and pulls like a freight train up top, so, you get out of the gate. Otherwise, it turns into a pedal fest, and you go no place fast.
I have run 240cc, fully ported Dart Pro-1 230's on as small as 380 inch, for a "street" car. The engine was a solid roller, 11.5:1 pump gas deal, that made 600hp, and still made over 500 ft/lbs. It was built with a 350shot in mind, so, the big heads really don't hurt. It was still an animal on the street, at 2800 lbs, with driver, 66 Chevy 2, it went 10.20's at 130mph on the motor, so, if that is respectable, for what most guys would say is to big a head, then, I don;t what to tell you
Frank
Advanced Performance
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