I need some help from some of you SBC guys here. I have a set of #416 small Chevy heads and was just wondering what needs to be done to them in order to get moderate performance from them? I'm looking for approx. 350 HP if possible. I have a Ultradyne 229/229 duration .480/.480 lift (110 LSA)cam that I was thinking about using. Thinking maybe dished pistons to keep compression low enough to use on pump gas. Would this combo work? Trying to build a nice 90% street/10% strip motor. No high dollar components.
Set me straight where/if I've gone wrong!

I haven't searched out the advertised duration numbers for that cam but usually a "229ish" sized cam at .050" lift is right at 280 and 292, depending on whose it is.

Therefore I figure you will need at least 10 to 1 CR. to run it and then you will start having to match the motor combination well enough so you can still burn pump gas..

Please think about this, b/c I mention it b/c if you try to run a cam like that at a lower CR. number, it will run OK, but NOT at it's full potential which the higher CR. allows it to until you get into the poor octane ratings of todays gasolines..

Been there, done that BUT not very well, imho...

pdq67

305 ho heads if i remember correctly have 1.94 int 1.50 exh and 58cc cumbustion chambers they will take a flatop 4 valve relief piston into the 10to1 compression range ive used them before and see no problem gettin 350hp out of them with a port match on the intake and a little taken outa the bowls you should be fine. they wouldnt be my first choice but they are decent heads for the budget minded performance enthusiast. good luck my 2 cents

The 416 heads have 1.84/1.50 valves. I've run the 416 heads, ported and intake matched on my 327 with a 216/228 @ 0.050 lunati cam, eldelbrock performer and headers and I wasn't impressed. My compression was about 9.5 to 1. In order to get the high performance out of them you need to have the valves upgaded to 1.94 on the intakes and then unshroud them and have the intake and exhaust runners opened up to 170 CC or better. They have potential but you have to do a lot of work to get it out of them. I converted to a set of vortecs and you wouldn't believe the difference. Like night and day. I think they would be a much better match for a 283.

Clyde

My pair of old 305HO, -601 head's cc'ed at 160+ and a lot smaller, like down to below 55 cc's chamber-wise which really shocked me b/c I was figuring 150/155 or so intake ports and 58+ cc chambers.

GREAT 283 heads imho b/c that's what they are going on..

pdq67