Motor mounts small block vs big block?

W

wickd

Active member
Joined
Aug 27, 2009
Messages
42
Got a question about motor mounts. My car came with a small block from the factory and years ago I put a big block in it. I used the same motor mounts and just bolted the big block in with no problems. I have seen posts about motor mounts and some people talk like there are different mounts for big blocks in vettes. Does anybody know about that? I am just starting on a c-4 suspension conversion for my 72 and the first thing I need to do is set the motor and the 4l80e trans in place and make the trans crossmember/trans mount mods before I do anything else and I want to make sure I am using the right mounts on the motor.

Thanks,
Mike
 
The motor mounts are the same SB & BB.

The originals are non locking and some use the locking mount, but phyically the BB and SB are the same.
 
I've seen this question asked several times in various forums. I think a contributor to confusion about motor mounts is that Chevrolet automobiles came with two designs of motor mounts. I ordered a set of new motor mounts when I was going to install my ZZ4 in my 68. I ordered them from a local performance store. I'm pretty sure the parts catalog said they were for a SB. They didn't fit. Anyhow, I ordered the next set from a Corvette vendor just to avoid any more hassle.

Where the motor mounts bolt up to the frame horns...the frame horns come in two widths, one wider and one narrower. I forget which width Corvette frame horns are.
 
Gentlemen & the Ladies present with regard to Corvette and only Corvette (I don't know a thing about other Bowties or other GM carlines)

1963-1969 originally used what is termed a non locking motor mount
1970-1982 originally used what is termed a locking motor mount

There are actually interchangeable & either can be used on any 1963-1982. The only restriction is as follows. If you use locking mounts on a 1963-1969 Corvette, the lower spark plug wire "V" shaped ignition shields need to be notched to clear the mount. Can be done with metal snips.

PS I never broke a Corvette motor mount but all my Corvettes have been stock 360, 390, 400 or 435 horsepower's, not the mega fat blocks with enhanced aspiration.
 
You must log in or register to reply here.
Top