3x2 Carb Stud Length

[William H.]

I was told my car studs on my 3x2 Holleys were too short during a local Chapter event. Does anyone know the correct length of the studs connecting the carbs to the manifold? Also, what is the finish of the center carb stud holding the air cleaner? Thanks much.

[Joe L.]

Re: 3x2 Carb Stud Length

I was told my car studs on my 3x2 Holleys were too short during a local Chapter event. Does anyone know the correct length of the studs connecting the carbs to the manifold? Also, what is the finish of the center carb stud holding the air cleaner? Thanks much.

William-----

Your application was supposed to have used GM #3959570 carb-to-manifold studs. If that was actually used in your case, the upper thread length is 0.8" and the total "above-the-manifold" (including unthreaded shank) length is 1". Be aware also that two of the carb-to-manifold positions use bolts, not studs.

I believe that it's very possible that studs other than the above were alternately used and that these studs may vary somewhat from the above dimensions.

As far as the air cleaner retaining stud goes, I'm not sure. I believe the 1967-E68 stud was zinc or cadmium finished. However, I'm not sure about the L68-69 stud, GM #3928912.

[William H.]

Re: 3x2 Carb Stud Length

Thanks, Joe. Very helpful. Do you know who sells the correct length studs. I bought a few from Paragon and or Zip and they are .15" short. Bill

[Mark D.]

Re: 3x2 Carb Stud Length

Richard Fortier has them in a very accurate reproduction. For your application, it should be dark/black phosphate.

[Joseph W.]

Re: 3x2 Carb Stud Length

Richard Fortier has them in a very accurate reproduction. For your application, it should be dark/black phosphate.

Resurrecting this thread from many years ago.
What is the finish on a 1969 tri power manifold carb stud?
I thought the JG states the are zinc di chromate plated which would be a gold finish.

[Gary B.]

Re: 3x2 Carb Stud Length

The one on my April 1968 build looks to be a zinc-dichromate finish.
Both 69's here look the same.
Gb

[Joseph W.]

Re: 3x2 Carb Stud Length

Thank you Gary!
Ive bought all the stuff to DIY zinc plate and also zinc dichromate my hardware.

[Ed H.]

Re: 3x2 Carb Stud Length

Joseph,

I looked at my March 1, 1968 build with the 427/400 and they look to be zinc-dichromate finish as well.

Ed Harbour

[Tom D.]

Re: 3x2 Carb Stud Length

Bolt might have been changed, but this 1968 setup has been sitting here for years! It came from a guy on long island...
68 intake bolt - 1.jpgrear view