Does anyone know how to adapt a gm manual to a cad 500? I know companies sell a billet flywheel and a bellhousing for about 750 but I think there has to be a cheap way. I know I can buy a cheap adapter to mount a chevy bell and I also know that the buick olds pontiac automatics will bolt up. So I should be able to use a manual bell from a muscle era pontiac. Cads have a 166 tooth ring gear and are internally balanced as are the pontiacs. if the flywheel from the pontiac does not bolt on to the cad I am guessing all I will have to do is redrill the cad bolt pattern into the pontiac flywheel and maybe do some machining on the indexing center hole. This is all late night theory that fell on the table so any solid info would be wicked! thanks
I too am interested in the answer to that question. Sounds like you have a good start with your theory.
you have to buy a standard flywheel for the cadillac,the pontiac will not bolt up. the pontiac bell housing will work,and you can buy the pilot bushing you need. this has been done lots of times. go to www.cadillacpower.com everything you ever need to know about cadillacs is there.
I did it for my '70 Edlo 500. The pics are on my work computer so I'd need to post them later, but I used a flywheel from Maximum Torque Specialties, www.500cid.com. When I opened the box it had a Mondello label on it, so they're just reselling a Mondello Interita flywheel for the Caddy 500. You could also try Mondello at www.mondellotwister.com. I originally tried to use the Olds/Poncho Lakewood SFI bellhousing I had for my Olds 455, but the starter on the Pontiac/Olds engine is on the driver-side, so your best bet is a Buick bellhousing since it's got the starter on the pass. side like the Caddy. Lakewood makes an SFI or you could find a factory one from a Buick muscle car or maybe even late '60s Jeep pickup or Wagoneer (not sure if the Jeep one will accept a GM tranny). A regular Centerforce 11-inch GM Dual Friction clutch & PP bolts right to the flywheel. One big thing - the Caddy crank isn't drilled for a pilot bushing. You've got 2 options - either yank the crank and have it drilled for a standard Chevy pilot bushing or turn one out of bronze that indexes the large ID in the back of the crank. I chose the latter from a chunk of oil impregnated bronze. Since my way put the bearing closer to the tranny I had to nibble off about 1/4-inch of the input shaft splines to keep them from bottoming on the pilot bushing. Also, you'll need to either drill the crank about 1/2-inch deep to keep the input shaft pilot tip from bottoming on the back of the crank or lop off a bit of the input shaft. I just used a Hole Shooter with a 3/4-inch bit (or maybe it was a little smaller - did it almost 8 years ago) to make room.
Thanks for the info guys. Dummys got the good stuff! I am going to see if my parts man will slide me a pontiac flywheel to inspect. I will see if it can be done with a little machining.
Good luck using the Pontiac flywheel. Hope it can be done. The one I got was specifically for a Caddy . Found a couple pics. One is the flywheel mounted with the custom pilot bushing. If memory serves the OD of the bushing was close to or the same as a Ford. Only the Ford input shaft pilot is larger than the GM tranny, so you can't just use the Ford bushing. The other is of drilling the crank so the input shaft doesn't bottom
I have a Caddy 500 backed with a chevy SM 465 4spd. I got tired of killing TH350's so i felt the swap was quite worth it. This is all in a 74 Chevy 4x4 this is the flywheel and bushing i got right here... http://www.cad500parts.com/catalog/page27.htm I used a dremal with a rasp to fit the pilot bushing in the crank and used the adapter plate i had i was using for the auto. Easy Swap and well worth it.
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