78 omega 468

I need the frame mounts to put a 403 in my 78 Omega that was originally a V/6 car. I was told if I could find the frame mounts I could buy the motor mounts from a parts house.

svnt442

The frame mounts are the same as the Chevy mounts and are very common. Joe told you that in the other thread.

The harder part to come by are the conversion mounts used in the T/As on the 403. They can be found used and I think there are even some new ones being produced but I don't remember where I saw them.

78 omega 468

http://transamcountry.com/community/...1668#msg191668

78 omega 468

https://classicoldsmobile.com/forums/197023-post3.html these are mounts I want to find. Dave Chandler home 318-635-8972 cell 318-344-5983

RATCHETMASTER

Randy
the mounts are not the same as the chevy.

IF you can find a 77=79 cadillac seville, they have an olds 350 in them with the correct mounts.

joe_padavano

OK, this has become WAAAAY more confusing the more I look into it. First, keep in mind that we said the FRAME side mounts were the same between the Olds and Chevy motors. Obviously the metal block-side brackets are different, and we've discussed this in the original thread.

HOWEVER, it turns out that the frame side brackets have different part numbers, though they appear to be dimensionally interchangeable.

Anchor 2387 is listed for the 403 F-body:



Anchor 2292 is listed for the SBC F-body:



You will note that the mounting bolt holes and cross bolt hole appear to be in exactly the same places. I'm betting that the difference between the two mounts is related to the hardness of the rubber or some other second-order effect.

Even more interesting is the fact that the Seville mentioned above uses the 2292 mount which IS the SBC mount, so obviously the Olds block brackets will fit either 2292 or 2387 frame mounts.

78 omega 468

Probably nothing but comparing the 2 the lower mount is crowned above the cross bolt hole, the other counter sunk.

joe_padavano

Yeah, that's kind of obvious. The important dimensions are the location of the holes that bolt to the crossmember, the location of the hole for the cross bolt, and the overall dimensions of the part. The engine side brackets are the same, so it's a high probability that either mount fits in either application. Keep in mind that the factories regularly tuned motor mounts to reduce vibrations in certain cars.