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  #16 (permalink)  
Old 05-11-2007, 02:33 PM
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So does anyone know of anything I need to look for with doing the install or have any tips/pointers that might help me get it done?

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Old 05-11-2007, 03:23 PM
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I think we pretty much bashed this idea into few options for you.

The limiting factor is the old Dual Range Hydro-Matic transmission. It only bolts to pre-1964 engines. The new 64 up BOP-C bolt pattern on the block doesn't accept the older bell-housing. The Chevy bolt pattern is different again and while it possible to purchase Chevy/BOP-C adapters; the only source of 64 and up BOP-C or Chevy to Hydro-Matic transmission adapters has long ago dried up.

This limits you to using a pre-64 Caddy engine, there's worse things in life, if you want to retain the DR Hydro-Matic. Or:

1, You get lucky and find an old B&M adapter Chev to DR Hydro-Matic at a swap meet, Hemmings, e-bay, something like those places. Or you stumble into a 64-up adapter for BOP-C which would let you use the more modern Caddy V-8s.

2, You change to a TH-350/400, 700R4/4L60, 4L60E/4L80E gearbox which will let you run any modern GM V8. Once again this is simpler as Chevy to Chevy; but Chevy can be commercially adapted to 64-up BOP-C and some of these came with both bolt patterns.

Lastly you need to realize that the Cad's value to collectors goes way down with any non numbers matching engine and a non-original type transmission. So I guess before breaking the numbers matching stream you have with the 390, it would have to be a basket case before I go down that road.

If you don't care about numbers matching and want to be in a world where parts are available at reasonable prices, my modern response would be a BBC with a TH-400 or if wanting more recent technology, still a BBC with a 4L80E. The latter gear box will give an overdrive 4th combined with a lock up converter for really efficient, slow RPM cruising. Plus it has a really deep low, like your DR Hydro-Matic, to launch this heavy car. If you went for a fuel injected BBC this would be a super set up.

You could do a 350 or even a 383, but from where my experience has been, when you talk a car that's as heavy as a modern 3/4 ton pick up, you'll be happier, longer with the engine and transmission from the 5000 pound truck. It's not that you can't get power out of a SBC, but asking it to that and move 5000 pounds of vehicle really reduces its life span. Besides a 350 just wouldn't have the torque to launch the Caddy, espacailly with a TH-350 transmission. which has almost a ratio higher low gear and no OD. Getting the Caddy launched takes a lot of torque, this really takes some cubic inches from the engine where a long stroke is better at torque on the bottom end where it's needed with this rig; and it takes some steep gears to help get it launched. I think an SBC with a TH-350/700R4/4L60/4L60E is in over their structural head. I' mean they'll do, but it just won't last.


Last edited by oldbogie; 05-11-2007 at 03:37 PM.
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Old 05-11-2007, 04:19 PM
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Originally Posted by 62cadillac
well my main concern was to find something that anybody can work on for cheap. I've already purchased a 350 Chevy Engine and 350 Turbo Trans to do the swap. I'm not trying to build a Race Car or anything, just a Daily Driver that I can depend on.
If you want something to work on for cheap a 62 Cad might not be it, even with a chevy motor. In my opinion you are just ruining a good old car putting a cheap engine in it. Good running cad engines can be had for cheap. I have had 425/th400s given to me just to haul them off. A caddy deservs a caddy engine.
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Old 08-16-2012, 03:49 AM
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did 62cadillac ever fit the 350 chev into the caddy. we are also doing the same conversion with 350 crate motor and new turbo 400 trans and twin 4 barrel tunnel coming as well. costs in new zealand to rebuild our tired old 390 caddy deemed it over the top. the 350 chevy will blitz the caddy be reliable and parts easy to get. our caddy can be seen on youtube under pink cadillac lowrider its a 1962 coupe deville
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