454 Big Block??

[Mastique]

Will a 454 Chevy Big Block fit in a 1959 Cadillac Eldorado??
Please send your answer to: [email protected]

[The ORIG. Dig. Oxy]

It has once been said that if you need to ask a question like that, then you will wmost likely not be able to afford it.

[kaskillah]

You must be joking. Sure it'll fit, but why go through the trouble.
The original 390 has plenty of power and there was a tri-power option all well. It would be a sacrilege to put a Chevy engine in a car as collectable as a '59 Cadillac. If you are set on doing some engine swap consider the Cadillac 472/500 c.i. engine. You'll be keeping the car all Cadillac.

[Firehazrd]

You have a point with the '59, but I've got a different situation. I have an '84 Caddy Deville Hearse (stretched). I pulled the motor for a basic rebuild and realized it was the 4.1 liter 250cid with a ht250 tranny. That is not a combo with enough attitude for a hot-rod hearse(or enough horsepower to move two devilles welded together with 6 people reliably cross country). I obtained a 454 out of an'80 GMC truck and got a th400 for next to nothing. now I get to figure out how to mount it. I have measured and it will fit,no problem, but the stock caddy mounts didn't line up so I removed them. The frame has holes for different options- I'm hoping GMC motor mounts will bolt to the other set of holes. If all else fails I can weld something in. the only thing I can find is this

http://dsc.discovery.com/fansites/mo...pisode_41.html

and they discuss "custom made motor mounts" so I'm a little nervous. Any advice would be welcomed and appreciated.
thanks,Robert

(I know this should be in "devilles" or "non specific", but I found this thread in a search and just replied- Hopefully It'll get the same attention as if it was posted properly!

[MagicRat]

I put an Olds 455 into an '81 Fleetwood. Your hearse has the same frame, at least the front half. The 400 trans was used in these cars through 1981. Find one of those to donate the transmission mount and driveshaft, if yours has the same wheelbase as a 4 door car.
With the 400 trans located properly, install the engine and bolt it up to the trans in the stock location. Use 454 car mounts (ie old Chevelle) and bolt them to the block. They should sit right on top of the frame cross member. Check for clearances and location, maybe shim the mounts if necessary and weld them to the frame. I did this procedure with the Olds 455 using '68 Toronado engine mounts and it worked fine.
The key here is, other than clearances, the driveline must maintain the same angle as the rear axle pinion shaft, in order for the driveshaft to function without vibration.

[Firehazrd]

Thanks for the advice- Part of my problem is the driveshaft. It is actualy 2 smaller driveshafts with an extra u-joint. I was thinking of replacing it with a custom long single one, but someone pointed out the reason it is split is probably for clearance issues. I'm hoping it will be strong enough (along with the stock rear end) for now. Maybe the split design will ease instalation(I hope).
I think I'll be able to mount the th400 no problem, since I've pulled them out of caddys before. I don't know if the yoke is the same for a th250 as a th400-probably not. I'll probably need some custom driveshaft work.
I was planning on getting GMC truck mounts, are chevelle or car mounts any different?