To the best of my knowledge and belief the following has occurred,
please correct me if this info is incorrect.....:
Thanks to you guys that have answered my request and some other
research I have done, I have accumulated the following info:
The so called "power pack" heads were manufactured in 57 only with a
single point and casting no. 3731539... they were used on corvette
283 's and on other installations with F.I.
| | Looks something like this. There is reports of a
mysterious casting that has two points and I remember seeing them
when very young but could find no info...maybe see below.
Heads for the 2X4 carb installations had a casting no. of
3731762 and were manufactured in 1956 for the 265 cu.in.F.I. corvette
The camel humps (use your imagination) had the following casting
numbers and had all sorts of changes and features:
3782461X..1960-63 283/327..172/64 cc port volumes
3782461 ...64-66 327 .. 160/62 cc p.v.
3890462 ...66-67 302/327/350
3917291 ...67-68 302/327/350
3917292 ...68 327/350
3927186 ...69-70 302/350 64cc chambers
3927187 ...69-70 350 64 cc chambers
3973414 ...70 350 LT1-370hp 64 cc
3991492 ...70 350 LT1-straight or angle plugs 64cc
you can check these numbers at this url
These heads were intended to be run on a 283 and as such have small
ports and valves( by todays standards). They also were intended to
run on leaded higher octane fuel. I'd suggest they be used by
someone who needs those heads for a '57 restoration and buy
a set of Vortec "L31" cast iron heads over the counter from a Chevy
parts outlet. They flow a lot more air, have 1.94/1.5 valves, 170cc
runners, fast burn chambers and would work much better on a 350 than
the old 283 heads. The Vortec heads require a matching
intake from Chevy or Edelbrock and cost complete for the pair is
about $385.00. They are the best performance bargain on the market
today. By the time you add bigger valves to these old heads and have
seat and guide work done and have "hardened" seat inserts installed
so you can run today's low octane unleaded fuels, the rebuild costs
will equal or surpass the price of a new set of Vortec heads.
I will accept and appreciate any corrections to the above anytime and
thanks again those who have added their experiences and comments...
fact of fiction!
51-3100 AD Stocker