I Have a built 454 that I'm wantin to put in my 1965 Cadillac. Came factory with a gm 429, anyone know if the motor mounts are the same? Posted using the Full Custom H.A.M.B. App!
Nope, everything is different. No interchange at all, except for the distributor cap, rotor, and points.
Plan on changing the bellhousing or transmission too, different bolt patterns there as well. Might just be easier and cheaper in the long run to sell the 454 to raise cash and rebuild the 429 properly. 340 Hp and 480 ft-lbs of torque from a stock 429 is nothing to look down at. A little compression bump, the right cam, and better flowing exhaust and intake, and those numbers could easily rise, with out much addition expense over the stock rebuild. Hard to imagine doing a 454 cheap enough to offset all the other costs involved with a motor swap and still match the 429 performance numbers.
Some time in 65 Cadillac changed to the BOP bellhouse pattern if you have the late pattern keeping the trans is easy and the 472 and 500 will bolt up.
Yeah, your right about that. I probably should have looked up the fact that the 429 was a 10.5:1 motor to start with. Still beats the hell out of 90% of the stock 454's out there. Very True, but even if it is the BOP style bellhousing, it is still different from the 454 he want's to drop in. It will still require an adaptor or a bellhousing / transmission change. The 472 / 500 is an interesting option though. People normally give those monsters away for little or nothing (at least when gas is closer to $4 /gal).
FrozenMerc, The later trannys came with a dual bolt pattern, BOP and Chevy/gmc. But the four lower bolts and dowel pins were the same on both transmissions anyway, and you could run 'em without the top bolts just fine. Something to think about is that one the 454 is built already and chevy transmissions are cheap, way cheaper than old Cadillac transmissions. The 472/500 option is always a way to go but all said and done if I had a big block chevy already built and sitting it would be my first choice.
The 200-4R was the only transmission that usually had a BOP and Chevy bolt pattern. None of the 400s did, a few of the 350s did, 700 was only chevy. The lower two bolts and the dowels are the same, the upper four bolt holes are different. Woudln't be a real difficult swap to put a 454 in there if you have one with a transmission already...but you'll need to treat it like most engine swaps, and be prepared to change everything.
Speed Yes but in the day of $500 adapters Speedway sells a BOP adapter for $40. I have replaced two 454s in 3/4 ton Chevy pickups with 472 or 500 cads and both truck got better milage after the swap.
Had a 79 Cad Coupe de Ville w/454 & Turbo 400......swap was a bolt-in and used Cad 4 bbl carb which already had all hook-ups......Cad was triple black & a great cruiser, even towed my 26 ft Wells Cargo with it, after putting air shocks in rear......
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