Quote from: x66 714 on September 12, 2026, 12:45:21 PMThey may be more concerned about the original high dollar mounts & not see the bolts...Joe
Hoping this is the correct spot to ask some follow-up questions.
The engine mount FAQ www.camaros.org/engine.shtml#EngineMounting says 1969 302 and 350s used the "special" frame stands 507/508. Many posts discussing the ZL2 hood seal fitment on 302's need to have the correct stands, mounts, intake and carb for the seal to have the correct gap to work properly. Mismatch those parts and you have seals that are too tight or too loose. OK so far?
But the FAQ also says 507/508 were used on 350s. I can see 350s for Pace Cars needing those stands as they all had ZL2 hoods. But what about L65 350s? And a non ZL2 SS350's? Did they all receive the 507/508 stands? Or did they get the "standard" V8 183/184 stands?
While my SS350 (non ZL2 and Van Nuys June 69 strike build) may not be a valid data point, it did come with 183/184 stands.
Now back to bolts (which are not in the FAQ or in the judging book). 183/184 bolts are 3980716. Pretty sure this is a 3 7/8" length grade 5 bolt originally, even though you cannot get this anymore. AMK and other catalogs lists 3980716 as a grade 8 7/16-14 x 3 7/8 bolt (which really is a steering box bolt doing double duty).
But the AIM calls out bolt 3977984 as the bolt for the 507/508 stands. No reliable info on this bolt that I could find.
But recently I researched motor mounts that fit the stands. Anchor 2285 mounts fit the 183/184 stands with the 3980716 bolts. Anchor 2283 mounts fit the 507/508 stands (listed on sites as applicable for 69 396) used in 302 and 350 small blocks. But the 3980716 bolt was too long IMO. I found 7/16-14 grade 5 bolts in my boxes that are 3 1/2" and fit much better.
Not sure if 3977984 bolt is longer than the 3980716 bolt, or shorter (there would have to be some difference hence the different part #s and the Z28/A4 AIM page shows a spacer.
Anyone know?
ps: the BB mount bolt is 3977980 which specs on it is also MIA. 7/16-14, but length is not showing and is not sold. It also has a spacer with no length shown. What do BB owners use?
Thanks
You are better off with having your questions in your own thread. I split your post out.
From Dave Pozzi.
I'd really try for a stock bolt because the end is pointed and the head has a washer built into it.
GM# all bolts are 7/16 X 14 threads/inch
3840748 4" 1969 early
3977984 4 7/8" 1969 late
3980716 3 7/8" 8 cyl engine 1969/8
3977980 4 5/8" BB engine
Probably more information if you look on his site. He knows a lot about suspension stuff.
https://www.pozziracing.com/
Engine stand stuff.
https://www.pozziracing.com/camaro_engine.htm