Hey guys im looking for some help with motor mounts. I sold my original motor (85 305) and left the block mounts on it but i still have the frame mounts. Is there anywhere i can find just the block mounts or do i have to buy both the frame and block mounts? I looked on summit and didnt find much other than solid mounts and they wont work with the original frame mounts. Anybody have any part numbers for the block mounts?

 

GM part numbers:

10213125 LH
14039436 RH

A lot of different applications used them. You could probably find them in a junk yard.

You can get them new from gmpartsdirect.com for about $40 for the pair.

 

Thanks for the part numbers, would it be wise to install solid mounts or poly mounts? or will the original stock mounts work fine? Btw the motor going in is a 383 with around 450hp.

 

*Chanting*
poly.
.......poly.
..............poly.
A big motor is going to wrench & pound the snot out of whatever is trying to hold it down. You can save money if it is a "track-only" car and use solids.
If it is going to have humans riding in it and a CD player on the street don't use solids. Everything in the car will be like a chainsaw idling on concrete, just wandering around with the vibration.

 

Poly mounts, the normal block mounts (the funny stamped pieces with the 3 holes) should be fine as is (stock ones that is).
Make sure you put them on the correct sides, otherwise you'll have a heck of a time lining up your engine

 

So i crawled under the car and took a look at the frame mounts and im thinking " man, these dont look very fun to replace". Is it really worth the hassle or will the original mounts work fine? This isnt a track only car, actually it will be mainly a street car, so solid mounts are out of the picture.

 

You can use rubber mounts, but if these are original, they're probably worn out.
I used new rubber ones on my car, FWIW. Also a rubber trans mount.

If you think you'll be replacing A-arm inner bushings, or front springs anytime in the future (at all foreseeable future), do them now, and once the a-arms are out for either (or both) of those components being fixed, the motor mounts become EASY AS PIE to replace.

 

On the other hand, if you do them with the A-arms in place (like I did), buy some "disposable" long 15mm box end wrenches that you can bend to match the nut head inside the box beam of the front crossmember.
It's a labor of love but rubber "ages" and most folks just say "the heck with it" and have an engine that flops around on 20 year old rubber.
Here's mine after about 2 hours of toil: