05-07-04, 05:09 PM
I am new to the site, and have a few questions about these torque making motors. I have my set on a 72 coupe de ville for a couple hundred, the man selling it says it ran a couple years ago before he parked it, befor that it was his daily driver. It has the 472 in it and the body is shot. I want to put this motor in my truck (77 Chev short box 4x4) I know abot the need for a BOP tranny, and the motor mounts, are there any other surprises that I should be on the watch for? I was figuring on building a custom crossmember for the motor mounts, so I don't think the oil pan will be an issue? I was wondering about the ignition, is there an easy and cheap way to get HEI on there or will I have to go with MDS or somthing similar? I have a friend that is a machiniest and love to make snow mobiles go fast for a hobie, He does the porting on his and his friends heads, Would this be a good thing to get him to do on mine? His sled currently makes 240+hp and does the 1/4mile pavement at over 140 mph. I don't want top end power, I want low end grunt. Any sugestions? I can't wait till I can start playing with my new motor...:D
05-07-04, 05:41 PM
Don't port heads without using a camshaft that can make use of it. Porting and cam will increase top end power anyway. Petronix makes a points to HEI conversion kit for the distributor. I believe Crane does also. They both work very well....There are some cam grinds out there that will increase low end torque without raising the RPM's of the engine. They are usually used for towing applications. Hope that helps some... :) Caddy flexplate doesn't bolt up to Chevy torque converter and motor doesn't bolt up to Chevy tranny. Flexplate can be drilled to fit converter . There are adapter kits available to.
05-09-04, 06:46 PM
A cross member isn't needed for the motor mounts. You just need to either fab frame mounts, use the 77-79 deville engine mounts and frame mounts or contact one of the Caddy vendors.......they have universal motor mount kits. Allante North* may be able to shed a little more light on this. He ordered the mount kit from CAD Co. for the 500 swap into his El Camino........Don?
05-17-04, 04:50 PM
So if I use the caddy torque converter, will I be Ok assuming that I'm using the BOP tranny? Also, the 77-79 deville motor mounts, are they the easiest to use for this swap, if so why? Cooling, will my rad from my 350 be able to keep this motor cool, or will I need something larger?:hmm:
05-17-04, 05:39 PM
I'm changing my radiator in my Chevy (with 350 engine) for the 425 Caddy engine because the 350 rad is 3 row and the Caddy rad is 4. The 425 always ran hotter in the old '79 Caddy it came out of than the 350 in the Caprice does and I feel better with the extra cooling. Besides being 4 row, I believe it is a little bigger in width also and I think it's made to run with a little more pressure than the Chevy. The Chevy system is 15lbs. and the Caddy is 18lbs.Which also brings up the question of the heater core being able to withstand the extra 3 lbs. of pressure.I haven't crossed that bridge yet so I'm not sure what I'm going to do about that.(Probably wait for the heater to blow then curse and kick the car as I'm brokedown on the side of the highway :crying2: )
05-17-04, 06:31 PM
If the motor is stock, the stock converter should work fine. The Caddy flexplate has the large bolt pattern.....just make sure your converter bolt holes line up.
I was told the 77-79 Deville mounts work well in Chevy trucks.......I don't know from experience. I believe Al from MTS (Maximum Torque Specialties) has done this swap in his own truck (not exactly sure what year). You might give him a call to see what he has to say.
07-28-04, 08:22 PM
The Cadalliac motor mounts will work just fine on the Chevy Truck frame mounts. This is a mount that will have to be slid forward 2 to 3 inches to allow the Big block engine to set down in the engine compartment. There will have to be one extra hole drilled in the truck mount for the Cadalliac motor mount to line up for the four bolt holes. Use the Cadallic motor and transmission instead of trying to bolt back to the Chevy transmission. You may have to change the end of the drive shaft to fit the Cadallic 400 Transmission, but is will be a heavier duty spline that will help with the additional torque from the Cadillac engine. Do it & you will be amazed of the power to accelerate with a load on your truck. I put a 425 Big block in my Chevy truck & love it. You will need all the cooling from a good radiator, so use the Cadillac radiator, even if you have to modify the fan shroud area.
07-29-04, 09:05 PM
I did the 500 thing in my 73 1-ton, and had good success with an adapter to the Chevy TH400. One problem I did encounter was firewall clearance on the drivers side because the cyl. banks are offset the opposite way. I ended up using the universal mount kit from MTS with the old style stock mounts,it was pretty straightforward. Whatever route you go,you need that rear sump pan for sure. That 500 has more sack than the old 454 ever thought of. Pulling a heavy car trailer up a hill is effortless. It's well worth the time to do it.