462 double hump heads
#2
Safety Car
Member Since: Feb 1999
Location: Fountain Hills AZ
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Re: 462 double hump heads (rexx78)
Not by today's standards. Back in the 60's they were a big improvement over the previous heads and earned a reputation that hung on even after better heads were introduced. They're not a bad head, probably comparable to the L98 heads used on ZZ3's & 4's, but not as good as what's available now.
#3
Safety Car
Re: 462 double hump heads (Vetterodder)
462's were one of the best flowing production heads. They were used between 1962-1968 on various HP versions of the 302, 327 and 350. They came with either 1.94/1.50 or 2.02/1.60 valves, had 64CC combustion chambers, intake port volume should be 161CC's, exhaust port volume should be 65CC's.
[Modified by Stewart's74, 9:50 AM 11/21/2003]
[Modified by Stewart's74, 9:50 AM 11/21/2003]
#4
Le Mans Master
Re: 462 double hump heads (Vetterodder)
With pocket porting and port matching, they're still a damn good head. I have 1.94/1.50s that have been hogged out to 2.02/1.60, hardened seats, pocket ported, and port matched by Flow Technology some 16+ years ago ($150 back then) and the other day the car did 293 hp and 293 ft-lb at the wheels on the dyno. This is a mild 331 running 9.5:1, 600 cfm Holley, Performer RPM, 327/350 hp cam, and headers.
From what I've heard, the ZZ3 and ZZ4s (with more cubes) were doing 225-250 hp at the wheels (but about 320-325 ft-lb).
Iron heads do carry more weight and typically run a slightly lower compression, but in actuality, an iron head can make more hp than a similar aluminum head under similar contitions. This is because the iron holds the heat in the combustion chamber better and heat is power. At least that's what Smokey says about them, and I think he knows what he's talking about by now.
From what I've heard, the ZZ3 and ZZ4s (with more cubes) were doing 225-250 hp at the wheels (but about 320-325 ft-lb).
Iron heads do carry more weight and typically run a slightly lower compression, but in actuality, an iron head can make more hp than a similar aluminum head under similar contitions. This is because the iron holds the heat in the combustion chamber better and heat is power. At least that's what Smokey says about them, and I think he knows what he's talking about by now.
#5
Re: 462 double hump heads (rexx78)
Make sure that the heads have the assessory holes. These heads were used thru 1967 maybe 68. The replacement head that came out in 1969 for the DZ302 Camaro's were 186 casting. Exactly what I am putting on the 383, that I am building. Granted the new alum heads flow a little better, but what do you need on the street? The DZ 302 Z28 would run in the low 12's right off the showroom floor with the 186 heads, and that was crankin around 7200 RPM :chevy
#6
Re: 462 double hump heads (rexx78)
I don't know what your plans are for a performance motor but you might check piston availability for the 400 to see if what's available will put your compression/wallet where you want since the heads have a small chamber...before you spend any bucks on them that is