My car was originally a 327/glide. The motor mounts are not the original 327, but the frame mounts are. I would call these frame mounts "tall". I looked at Pozzi's web site, but I haven't had a chance to measure my motor mounts to see what I have. According to his site, I should have the 1 3/4" tall x 2 1/8" wide mount for 67, 68. These motor mounts are solid, but I don't know the dimensions. His site also says the height is different between LH and RH sides. Can a motor mount be on the wrong side? My car is a 68 btw.
When I bolt up the headers, the collector is literally snug against the passenger floor pan. The reducer won't even fit flat against the collector face because it (and the extension pipe on the exhaust) hits the bottom of the crossmember. I'm pretty sure the crossmember is the original for the car.
It has to be the motor mounts. I don't think anything else is different.
Thanks for your help.
Which bolts are you having trouble tightening? The reducer bolts or the header bolts at the head? I have a straight plug headed 350 and M20. Is yours the original combo? It wasn't by chance orginally a TH400 car, was it (the crossmember is different than all the others)? Is the reducer too high to clear the crossmember?
It sounds like you might possibly have a motor mount issue. There are two sets of frame/motor mount combos. Mine initially had the correct frame mounts and incorrect motor mounts so the engine sat too low. It sounds like yours is the opposite, a tall and a tall, although if they are factory mounts the tall motor mount shouldn't be able to slide over the tall frame mount. The 350 should have a "short" frame mount and a "tall" motor mount, at least on a '69. I have the correct original 350 frame mounts and the Anchor brand 2238 stock type motor mounts for a 396, which are the same as a 350 and 302. However, their parts application is wrong and they list the short mounts for a 350.
Here is a link to David Pozzi's site about motor mounts. There's no whay I would've figured my problem out without it:
As for the flex pipe, I bought two off eBay. They have a 4" flex section welded between two pieces of 2.5" ID pipe. My exhaust is 2.5" OD. I bought a set of 3" collectors from Summit with a 2.5" ID reducer, cut off a section of the flex pipe and a section of the reducer, and welded the flex and reducer together to make it as short as possible. I now have to see how much of the head pipe on my exhaust needs to come off and I will trim it, then slip the flex/reducer combo over the headpipe.
Here is a link to the ones I bought and a pic of mine: