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May 21st, 01, 10:41 AM
i have a set of double hump heads with #462 on them. can anyone tell me if they are 300 or 375 horse? thanks, "shat"
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oger May 21st, 01, 11:36 AM Could be anything from 275HP to 375HP. They were used on all 4bbl and FI motors. 82 May 21st, 01, 12:41 PM oger, is there any way to tell the difference? oger May 21st, 01, 12:52 PM Valve size the High Performance ones had 2.02 in and 1.60 ex the stds had 1.94 in and 1.50 ex. There is no difference in the heads most were the smaller valve ones but it is no problem to install the larger valves. Actually the small valve ones are better to start with when you enlarge the seat you are into fresh metal not an old worn out seat. 82 May 21st, 01, 01:16 PM ok. i had a guy at the nmca races in memphis this weekend tell me if it was #461 it was a 300hp, if it was 462 it was 375hp. so i was a little cornfuzzed! jblake May 21st, 01, 01:25 PM Check out this great website for block and head casting numbers.... www.mortec.com (http://www.mortec.com) 82 May 21st, 01, 01:32 PM thanks jblake, i tried them earlier and it just says the 462 was from a 62-67 327 oger May 21st, 01, 01:51 PM The 461 was the earlier version of the same head. It was used the same way. Grape Ape May 21st, 01, 01:59 PM The 461's and 462's are for the most part the same. The 462 has a higher spark plug location which make is more freindly to domed pistons and the area arounf the spark plug was relieved some making the chambers 64 cc's rather than the 461's 62 cc chambers. ------------------ www.grapeaperacing.com (http://www.grapeaperacing.com) Jonesy May 21st, 01, 02:01 PM Oger is correct.The small valve ones are better to start with. You can enlarge the valve seat and make 2.02's out of them. By the way, I like how accurate that MORTEC site is. http://www.camaros.net/forum/rolleyes.gif cerrem May 21st, 01, 08:19 PM Personally the #462 castings have a better chamber than the #461 ... Installing 2.02 valves will really do nothing for flow unless the chambers are de-shrouded..also the short side radius will need to be enlarged to about 85%.... and bowl blended and such.. a lot of $$ for nothing much... The only guys working over and machining the daylights out of these heads is for competition classes that restrict to stock heads... otherwise they are just used for restoration purposes... For mild street performance leave the 1.94" valve in there and do the porting and such yourself...you can even do the bronze-wall sleezes yourself... Then have the seats cut at a shop...this way you don't waste a lot of money into these heads.. If your going to spend$$ ...then get aftermarket.. CHEERS Chris | ||