C2 Manifold to Exhaust Pipe Nuts

[John M.]

Re: C2 Manifold to Exhaust Pipe Nuts

A variety of hex lock nuts ( and other neat fasteners) can be seen at the AMK Products website. (http://www.amkproducts.com/Catalog_PDF.htm.) From the main page select PDF catalog then PDF pages 39-55. GM exhaust inlet nuts can be seen on page 43, products B-12863 and B-10524. Hex slotted can be found on page 47. Hope this helps.

[Arnold P.]

Re: C2 Manifold to Exhaust Pipe Nuts

if i understand the previous posts; the stover nuts and predominatly marsden nuts were used for many years for exhaust lock nuts. isn't this contrary to the belief that gm used many suppliers for same hardware? and wouldn't we see many different "styles" of the lock nuts? also, were these (marsden) nuts used on the other chevies engines or even buick, pontiac,olds, exhaust pipes? thnnx for all of your inputs. pappy

[John H.]

Re: C2 Manifold to Exhaust Pipe Nuts

if i understand the previous posts; the stover nuts and predominatly marsden nuts were used for many years for exhaust lock nuts. isn't this contrary to the belief that gm used many suppliers for same hardware? and wouldn't we see many different "styles" of the lock nuts? also, were these (marsden) nuts used on the other chevies engines or even buick, pontiac,olds, exhaust pipes? thnnx for all of your inputs. pappy

Arnold -

The original post referred to the nuts on a 60's L-79, and I've never seen a Marsden nut on a midyear. GM definitely used multiple suppliers for the same part number, but the Stover "acorn" prevailing-torque nut used on midyears is a different design, with a different part number, than a Marsden nut.

[Gene M.]

Re: C2 Manifold to Exhaust Pipe Nut; still want a good photo

Jim----

That answers it. Thanks. I think I've got it figured out now. 63-82 with 2" exhaust used flange GM #3734402. This is the stamped steel flange with the curved, reinforcing lips.

1965-67 with 2-1/2" exhaust used flange GM #3850231. This is the thick, flat flange as seen on your car.

1968+ with 2-1/2" exhaust used flange GM #3915125. I think this is the stamped steel flange with curved, reinforcing lips (i.e. configured like the 3734402 except for 2-1/2" exhaust). This style also became SERVICE for all 63-67 with 2-1/2" exhaust after August, 1971.

I mistakenly though that the 65-67 2-1/2" used the same style as later. Now I know better.

The 66-67 2 1/2" small block system had a 2" connection at the exhaust manifold. Not 2 1/2" till expanded out about 12" away from exhaust manifold.

[John D.]

Re: C2 Manifold to Exhaust Pipe Nuts

if i understand the previous posts; the stover nuts and predominatly marsden nuts were used for many years for exhaust lock nuts. isn't this contrary to the belief that gm used many suppliers for same hardware? and wouldn't we see many different "styles" of the lock nuts? also, were these (marsden) nuts used on the other chevies engines or even buick, pontiac,olds, exhaust pipes? thnnx for all of your inputs. pappy

Pappy and gang, If you all want an exact looking repro nut they are being reproduced by the CAMARO guys. ssshhhh. JD

[Terry M.]

Re: C2 Manifold to Exhaust Pipe Nuts

Finally found a picture of the exhaust manifold to pipe nuts from my 1970. Just like Jim Durham's, Brian Tilles' and as Michael Hanson related above.