tony1784

finally dropping in the 383 and the motor mounts are about a half inch 2 far apart. what i mean is that i can get one side on but the other side then is about a half inch to far to the outside. if anyone has ran into this problem please let me know. i wanna get this in quick so it can see some track time before sumemrs over. thanks

Damon

SBC motor mount holes are basically all the same, unless you're using a really old block. Did you reuse the engine-side mounts off the old block? And did you reuse the stock frame-mounted engine mounts? In other words, was anything replaced when you swapped in the new motor?

Even getting the original mounts swapped left-to-right can sometimes cause problems.

johnsjj2

Make sure you use the clamshells off the original engine. The 350, and 305 clamshells are different. I have no idea why. I learned this after 3 hours of wrestling with a 355 going in a Monte SS, where a 305 formerly lived. If you have already done this, then I am of no help!!

FSTFBDY

iTrader: (33)

305/350 shells are the same...

Ive used em both befor... This last time I used clam shells out of a full size chevy truck.

tony1784

I'm lost here, i tried forcing the bolts through the mounts to see if i can "pursuade" them into place and all i did was tear the poly. So i went to exchange them and now i have a new pair to try with.

johnsjj2

I'm telling ya, the 305/350 clamshells are different. They are about 1/2" different. My Camaro had the same deal. I had to use the 305 shells as the 350 ones wouldn't fit.

tony1784

Thats what I'm using is the old clamshells off the 305

five7kid

iTrader: (14)

Baloney.

Different between f-body & Monte, but not between 305 & 350.

I'm using 350 mounts on the 396, for what that's worth. The blocks do not change, only the chassis into which they mount change. Only way this could be happening is if the mounts are for the wrong chassis.

johnsjj2

Then the wrong chassis it is. What I am referring to is the frame mounts with the rubber, and the shells are different, or have been different the 3 times I have taken part in the swap of a 305 to a 350. The 305 frame mounts have been about 1/2" wider, thus needing a 1/2" wider clam shell. A friend of mine back in high school even ran into this. His father and him took a 305 out of a 91 RS and put it into an 84 Capri. After their custom fabrication was done, all was well. When the 305 was ousted in favor of a 350, they had to use the 305 shells as the ones on the 350 would not go over the frame mounts. This very well could have been a freak of GM manufacturing, but it was just something to look at. But I don't think this is tony's problem if he is using the original ones.

TexasLT1

n/m

tony1784

i just used a 3/8 inch metal plate under the bottom edge of the mount to bring it closer i havent dropped the motor in yet but i took some measurements and it looks like it it will work

level

if it helps 305/350 motor mounts are the exact same. when I switched from a 305 to a 350 block, I went to autozone and 305/350 motor mount had the same part number.
the motor mounts didn't line up tho, because some idiot put the wrong mounts in the box. so when I returnd them I got the right ones. mounted no problem.
it's a PITA replacing the mounts with out the right extensions to..