SBC Engine Mount, Which Clam Shell?

[aotte1]

Upgrading my engine to a SBC 350 from a V6. Trying to select correct clam shell,engine mount. Have a set with the following part number 3993722. They may be from a 1972, Big Block??
Will they work for 1986, C10 short bed?

Can you use BB clam shells, with out problems, on a SBC 350.

thanks,
Les

[KrazyRay]

There are many different variations of clams, but any will most likely work. There can be a slight height difference in the holes for the long bolt. Some are more shallow to make up for the thickness of brace rod brackets. I posted a thread a long time ago about the differences between 72 big block and 73 up big block clams. The 72 clams have added resale value.

[aotte1]

Ray,
Thanks, installing engine tomorrow.

thanks,
Les

[craig113]

I am currently working on my BB engine also, after I pulled the engine I found a broken engine mount. Having mounts laying around in the shop, all SB, they are different by .25 inch in length and don't line up right.

84 K30, 454, Turbo 400, 205 transfer

[v30crewcab]

car ones are shallower than truck ones as well.

[aotte1]

photo of clam shell I found today, that maybe 1972??

[KrazyRay]

Here's a link to the clams: http://67-72chevytrucks.com/vboard/s...ht=clam+shells

[craig113]

Found the info for you...
the mount #'s you are showing fit a p20 or g1500 series for a 5.0L / 305 they should work fine

pg 0-93 of the 85-91 parts illustration parts catalog

1985-1991 292,305,350,...........pn 459021
1985-1991 454........................ 357717
1985-1991 6.2......................... 14071939