427 heads
Thread Starter
Racer
Joined: Apr 2009
Posts: 450
Likes: 6
427 heads
So I pulled my valve cover just to see what kind of condition the heads were. Which numbers are the important as far as 400 or 435? I noticed the GM3T but didnt know what number meant which head?
Well I just checked the manifold and verified its the 427 400 gm 3937795..
Well I just checked the manifold and verified its the 427 400 gm 3937795..
Last edited by Mikesfreetime; Jul 23, 2013 at 07:38 PM. Reason: edited
Burning Brakes
Joined: Apr 2013
Posts: 926
Likes: 2
From: Castle Rock CO
The GM3T casting will be the plant code from which it was casted. I did a google Search just on the GM3T code to find this answer.
Take a look at this site and it might help you out some more
I also used Google search of 427 400 gm 3937795 to find this site.
http://corvettec3.ca/casting.htm
Take a look at this site and it might help you out some more
I also used Google search of 427 400 gm 3937795 to find this site.
http://corvettec3.ca/casting.htm
Thread Starter
Racer
Joined: Apr 2009
Posts: 450
Likes: 6
The GM3T casting will be the plant code from which it was casted. I did a google Search just on the GM3T code to find this answer.
Take a look at this site and it might help you out some more
I also used Google search of 427 400 gm 3937795 to find this site.
http://corvettec3.ca/casting.htm
Take a look at this site and it might help you out some more
I also used Google search of 427 400 gm 3937795 to find this site.
http://corvettec3.ca/casting.htm
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
Correct heads are 3917215 for 68 and 3931063 for 69 400hp cars. The Corvette Black Book and The NCRS 1968-82 Corvette Specifications Guide list these numbers and other original part numbers. Both books are nice to have.
The 3937795 intake manifold was used in both years.
The 3937795 intake manifold was used in both years.
Last edited by Easy Mike; Jul 24, 2013 at 09:21 AM.
Burning Brakes
Joined: Apr 2008
Posts: 1,222
Likes: 93
From: shelbyville West Michigan
not to hijack, but I don't think that site is correct, it lists the L71 and L89 heads as same casting #. L71 is CI head and L89 is Alum. Shouldn't L88 and L89 have same alum. heads? or did they use the same casting number regardless of material?
