Schober Motorsports

Hey,

Could anyone help me out on this one? My buddy is looking to get some more power out of his Cadillac. I noticed that they used to put 350 Olds Diesel engines in these cars, so is it possible to get the 350 mounts and a late 60's Toronado engine n' trans and put it in? Right now the car is equipped with a Th325-4L (Overdrive) and is it possible to put in the TH425? Losing the overdrive isn't really a big deal to him.

What is there, if there is any, the difference of the TH425, TH325, and the TH325-4L? Are the bell housings the same for Olds Diesel blocks vs gas blocks? Any input will be appreciated. I apologize in advance if I put this in the wrong folder!

Thanks,
Craig

joe_padavano

The TH425 is based on TH400 internal parts. The TH325 is based on TH200 parts, and the TH325-4L is based on 200-4R parts. The trans will need modifications to live behind the 455. You can't easily swap a TH425 into this car because the trans mounts are completely different.

The bellhousings are all the same and the 425 will bolt into the car using the Olds motor mounts. You'll need early Toro exhaust manifolds and a custom-bent exhaust system. I don't know about any clearance issues due to the taller deck height, but it's possible that you may have valve cover clearance issues.

Destructor

The Eldorado of that body style once used the 368 Caddy engine which is the same family as the 472, 500. 500's mount into 80's Caddy rear wheel drive cars which had the 368 engines, oil filter fitting had to be used from the 368. With work it seems like a big block Caddy 472, 500 engine could work in an 80's Eldorado. It would be a neat project. It seems that an olds big block may also be made to work. Those years were nice Eldorado’s while Caddy's other offerings were going down hill (fit and finish), it's too bad most of those Eldorados had the terrible 4100 engine.

nonhog

Always liked the looks of those. I wonder if the stock trans could be udgraded to handle the extra power?

svnt442

I saw a 79 or 80 with a 455 under the hood years ago in about 1991 when I worked at Super Shops. So i know it can be done, I just don't know the particulars.

Schober Motorsports

Great to hear! He wants to do something with the engine... Right now it has that 4100HT crap that is only putting out about 135 horsepower!!!
Come on GM!!

Destructor

Find a Toronado or Riviera of that similar style, they used Olds 307's and some of those type Eldorados also used olds 350 gas engines, be gentle on the 4100. They need to be pampered to survive.