57 cam

[Paul Bowers]

are the orginal cam shafts from 57s hard to come by, how does one determine
if it is orginal and are they worth anything its just that I kept my old one when I had the ebgine rebuilt and just wanted to know a little about it, it has a (D) stampted on one end with a crude yellowish D painted on it also
thanks
paul

[William Clupper (618)]

Re: 57 cam

Not hard to come by, and used camshafts are generally not really fit for reuse.

[Duke Williams (22045)]

Re: 57 cam

What is the cast in ID number on the cam? Look between the lobes. It should be a seven digit number or maybe just four.

Duke

[John Hinckley (29964)]

Re: 57 cam

Paul -

If it's original, it'll have either "6098" or "3736098" cast-in on the shaft; I wouldn't re-use it. A blueprint replacement is available from Federal-Mogul/Speed-Pro as their #CS113R.

[John Hinckley (29964)]

Re: 57 cam - Addendum

The previous post assumes you're talking about the solid-lifter cam for the 270hp 2x4 or 290hp F.I. application.

[Paul Bowers]

Re: 57 cam

john and duke
the no. is 3736098 like you guys stated I was just curious after all these yrs. if it was orginal to engine, is that no. stampted on cam give me any clues as to orginal engine makeup even thou I have had engine rebuilt any how I was just curious..... also I just order new soft top for my 57 "white" car I chose "black" any coments on color or it just personal preference
thanks
paul

[Duke Williams (22045)]

Re: 57 cam

I have my original Duntov cam from my '63, too, and it has so little wear it could be reused, but it's a boat anchor. I should have it mounted on a piece of burl to hang on my office wall as a tribute to Zora.

Lift is insufficient for the big port/big valve heads on a displacement larger than about 300 CI. It has too much overlap for a street engine, but not enough duration for a racing engine.

It's a pretty good high output cam for small port/small valve heads on a small displacement SB, which is what it was originally designed for, especially when you consider that Duntov essentially designed it "on the back of an envelope", built it, tested it, and it worked - done deal. It was released, and won a bunch of SCCA Championships.

But big port heads and more displacement obsoleted it before it was actually replaced in production. The replacement 30-30 cam went overboard the other way. It was "too big" on a medium displacement SB to be an effective street high performance cam, too small to be a "real racing cam", but it's an excellent "hobby racing cam".

The Duntov cam was used on the 2x4 283/270, and 283/283 FI engines in '57, and was THE solid lifter cam through 1963.

You can certainly purchase the Federal Mogul clone that John listed as it will retain the original character of the engines is was originally used on, but I would raise compression to at least 10:1. With the 270's OE speced 9.5 CR (probably a true 9.0 as built) you don't even need premium fuel. FI engines with the Duntov cam had higher compression - 10.5:1 spec, probably 10:1 as built.

The L-79 cam has about the same effective duration, but more lift and less overlap, so it will broaden torque bandwidth and is more street high performance friendly.

Small port heads can be improved with pocket porting, and I think inlet valve size can be increased to 1.84". The larger inlet valve will improve top end power, but at some expense to torque since it increases effective overlap with the same cam compared to the OE 1.72" inlet valve.

There are severe limitations to what you can do to improve 283s with small port heads, so one good idea is to just restore it using all OE parts with no mods other than pocket porting the heads and maybe increasing the true CR to 10:1.

The 283 connecting rods are also pretty spindly and weak, so I recommend replacing them with the '66-up small bearing rods if you want to buzz it up to high revs a lot.

Duke