Q: I need a set of Chevy small block motor mounts for my 1969 Camaro. I’ve been told there are two sizes available. How do I determine which size is correct?
A: In the early years, Chevy used two different motor mounts. The “short and wide” version measures 2⅝ inches between the ears, and 1¾ inches from the engine mount surface to the center of the mounting-bolt hole. The “tall and narrow” mount measures 2⅜ inches between the mount ears, and 2 3/16 inches from the engine mount surface to the center of mounting-bolt hole. Simply measure your old mounts to choose the correct replacement. If you don’t have the old mounts, measure the width of the chassis frame stands. Remember, proper engine angle and header fitment depend on choosing the correct mount.
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Good information here. I also learned that many guys opt to remove a 307 in favour of a 350, or 396, 427, 454, etc. The frame stands on the 307 car will not fit 350, 0r BB motor mounts. frame stands are too wide, engine will not rest on the frame the way it should. you can simply install 307 motor mounts on the new engine, however they are known to be weak in comparison to other mounts. ( a good option here is to get moroso solid mounts for the block, they offer the correct width to accept the 307 frame stands) but the proper thing to do is remove the frame stands, and get the correct, narrower frame stands and use the stock 350, or BB motor mounts. WHY GM did this, I’ll never know. the 307 engineer must have not had enough coffee on a given morning. my .02
yep