I have always wondered why GM sold the wrong hood bolts for 63-67 Corvettes even back in Oct. 1962. I found an old thread (shown below) and I thought that I would try to answer Joe's question on the last post.
Pictured below are 3 hood bolts. I believe that the top two bolts (from a swap meet back in the 1980's) are GM # 3685619 as shown in the 1963-1967 AIM's. These bolts measure 2 1/2" in O.L. with a 15/16" head dia. As best as I can remember they are the same as my original 1966 hood bolts.
top bolt - When the bolt is assembled with the retainer, spring, and seat the measurement shown in my 1966 AIM (UPC 11-13, sheet B5) is 1.42" which leaves about 0.48" of thread length to install in the hood.
btm. bolt - NOS 3782560 bolt, 3 3/4" O.L., 1.00" head dia.
What confuses me is that the bolts listed in Gr. 8.085 in my vintage Chevrolet parts catalogs are as follows:
61-67 Corvette - 3782560 (1/2"-20 X 3 3/4" w/cone point) - service bolt
68-69 Corvette - 3915814 (2 11/64" O.L.)
69-76 Corvette - 3966625 (2 1/2" O.L.)
Paragon sell reproduction bolts as follows:
63-67 - 1" head dia.
68-69 - 3/4" head dia.
69-76 - 15/16" head dia.
Are the top 2 bolts in my photo GM # 3685619 or GM # 3966626?
Dave
https://www.forums.ncrs.org/showthre...=1298#poststop
Pictured below are 3 hood bolts. I believe that the top two bolts (from a swap meet back in the 1980's) are GM # 3685619 as shown in the 1963-1967 AIM's. These bolts measure 2 1/2" in O.L. with a 15/16" head dia. As best as I can remember they are the same as my original 1966 hood bolts.
top bolt - When the bolt is assembled with the retainer, spring, and seat the measurement shown in my 1966 AIM (UPC 11-13, sheet B5) is 1.42" which leaves about 0.48" of thread length to install in the hood.
btm. bolt - NOS 3782560 bolt, 3 3/4" O.L., 1.00" head dia.
What confuses me is that the bolts listed in Gr. 8.085 in my vintage Chevrolet parts catalogs are as follows:
61-67 Corvette - 3782560 (1/2"-20 X 3 3/4" w/cone point) - service bolt
68-69 Corvette - 3915814 (2 11/64" O.L.)
69-76 Corvette - 3966625 (2 1/2" O.L.)
Paragon sell reproduction bolts as follows:
63-67 - 1" head dia.
68-69 - 3/4" head dia.
69-76 - 15/16" head dia.
Are the top 2 bolts in my photo GM # 3685619 or GM # 3966626?
Dave
https://www.forums.ncrs.org/showthre...=1298#poststop