'67 fast idle cam

[William F.]

How do you determine if you have the correct fast idle cam for "67 300 hp non A.I.R. 3810 carb? color?
Thanks

[William C.]

Re: '67 fast idle cam

At least per the '68 parts book, all the smallblock holley carbs used in pass car and Corvette applications were the same part number, shouldn't be too much variation to worry about.

[John H.]

Re: '67 fast idle cam

Bill -

Most originals I've seen have an off-white/yellowish cam, and a few later replacements I've seen have a very light green tinge.

[William C.]

Re: '67 fast idle cam

I got a 1 point deduct with a black cam. Judge said it should be green.

[Clem Z.]

Re: '67 fast idle cam

Holley fast idle cams aren't referenced by their color, they are referenced by the cast in number right by the "steps" on the cam. Two of the more common GM cams are the "499" cam and the "539" cam. The 499 is typically white, but can be off-white or even a dark yellow-green. The 539 cam is commonly referred to as the "green" or "blue" cam as they are found in either color, but I have seen them in a very pale blue/almost off-white as well, which can obviously contribute to this confusion. "i got this from another website"

[Gerard F.]

Re: '67 fast idle cam

The white one, I understand, was correct for an original factory 3810. Most look slightly yellow with age. The green one was used on later replacements.

[Clem Z.]

Re: '67 fast idle cam

The white one, I understand, was correct for an original factory 3810. Most look slightly yellow with age. The green one was used on later replacements.

3810 uses a #539 fast idle cam

[Gerard F.]

Re: '67 fast idle cam

3810 uses a #539 fast idle cam

I have two fast idle cams take off original 3810s, both are stamped 539 and are white (actually vanilla to yellow with heat exposure). I think the current holley 539 is green and is used on replacements.

I also have a brand new 499 from Chicago Carburetor. It is white, and comparing it to my original 539s, it is identical, even in the stepping positions.

Maybe they changed the color on the replacements for identification.

[Terry M.]

Re: '67 fast idle cam

I seem to recall a 1968 TSB that changed the fast idle cam to one that was green. Might have been 1969. And right now I can't recall the reason for the change. I'll have to check at home tonight, if no one can pin it down before then.

[Wayne M.]

Re: '67 fast idle cam

Holley fast idle cams aren't referenced by their color, they are referenced by the cast in number right by the "steps" on the cam.....

Don't intend to hijack this thread, but is it possible that early Holley idle cams had only a single digit ident ? This cam is probably off an original '64 LIST 2818, [L76] dated 3A3 (Nov '63, 3rd week).

[Clem Z.]

Re: '67 fast idle cam

that looks like a holley part# 45-376 used on most all holley hot air and electric chokes. the ones we were referring to were for the divorce chokes,where the thermo spring was set into the intake manifold and a rod move the choke plate

[Timothy B.]

Re: '67 fast idle cam

I have two original dated 3810's and the fast idle cams are off white in color with (H-17 20) embossed like that by the steps of the cam.