2blu442

Hi All
I've got a 1974 455 that I picked up somewhere along the way. I'd not looked at it closely, but today I wanted to pull the motor mount heat shield off the passengerside. When I started to do that I realized it had these thick metal spacers on each bolt. The drivers side doesn't have them, only the passengerside. Has anyone seen these before, and if so are they factory? Do you know what the application was? John

toymobile

I think the spacers were used only on the big body cars, with the spacer only one set of mounts needed to be made to fit the complete line. JMO.

Johnny

Run to Rund

I also have some of those spacers, from early to mid-70s big cars, iirc.

joe_padavano

As shown in the Chassis Service Manual for the 1971-76 full size cars, 455 only. I suspect this has more to do with slightly increasing clearance to the HVAC box than anything else (the drawing says RH only). By the way, note the slightly different lettering on the callout for these spacers. This was clearly a last minute addition after this illustration was drawn.

dav45

Got a set on a 75 455 . all I needed to drop it in my 82 C-10 using Chevy frame mounts. Also used a set on RS on 74 455 in my 83 88 Royal. Used to gain clearance between RS exhaust manifold flange and frame.

olds 307 and 403

I also had to use spacers(big nuts) to make Trans Am mounts work where the Chebby Clamshell's were on my 94 Z71. Interesting they can be used in a few places. I wonder if they might help on a G body for HVAC clearance?