Hello all, This is not a thread to bash the 350 diesel but some rather honest questions from me.

I am a diesel nut and pro American. This limits my diesel choices fairly well. I want to put a 350 diesel in a older Cadillac and make the thing run off of vegetable oil. Ultimately I want a daily driver out of the deal. I am intimately familiar with the 350 diesel.

I recently stumbled across a cherry of a 1972 Cadillac Sedan with the 472. I was wondering what kind of and how much work will need to be done to drop a 350 diesel in?

The 350 gas and 350 diesel are relatively interchangeable.
Thanks!!

:thepan:

Sounds like a good idea. You will need custom engine mounts.
Turbo 400 uses engine vacuum signal for shift point control and the Diesel GM cars used a throttle detent cable. I've seen turbo 350 retrofits into diesel cars which used an engine mounted vacuum pump to supply a vac signal. Those cars were quite doggy though. The torque converter on the TH-400 is pretty tight compared to the ones on the 200 3 speed trans. Maybe a trans retrofit at the same time....Too much $$$$.
It would be neat to see what you land up with for fuel economy. I have a good friend who owns a '72 Hearse. That is one heavy beast and it uses plenty of gas. He uses it to haul heavy stuff also. The car sits around now in favor of a F*rd truck. This is obscene and needs to be stopped. A diesel conversion would be the ticket.
I won't do any bashing. Just a question. Can you get your hands on a turbodiesel? There are lots of good ones that will move that car. The 350 will be pretty s l o w.

adding a diesel engine , i thought about it too , my cad get terribled mpg , and its a 425 78 deville, and sometimes i wish it had a diesel engine, mine would be an easyer swap because that year car had a diesel engine as an option ? it think?

hey go to ebay there are some nos glow plugs for sale heres the link
http://cgi.ebay.com/ebaymotors/1978-79-350-OLDSMOBILE-DIESEL-AC-DELCO-7G-GLOW-PLUGS_W0QQcmdZViewItemQQcategoryZ33693QQitemZ80575 44538QQrdZ1

Sounds like a very heavy car for this engine in stock form. Would you modify this engine for more power (port/polish heads, headers/exhaust, timing gear, turned up pump and possibly turbo)? A stock 350 diesel engine has about 105 hp and 200 lbs.-ft. torque while the 472 in your Deville came with 220 hp and 365 lbs.-ft torque. This is more than twice the hp and almost twice the torque of a 350 diesel. You would also need to change out the rear end for something with lower gear ratios such as (3.08 or 3.73). Even a modified 350 diesel is going to have a hard time pulling this car with anything less than a 3.08 rear end.

Well the whole reason behind using the 350 Diesel, is the fact that I have three of them setting in my garage and one running (very well I might at) in my 81 GMC 1500.

I bought most engines for about 25-50 bucks and are collecting parts, mostly stuff people have and no longer want. Two of the engines are very rebuildable the third is parts only.
I would most likely couple the engine to a 700R4 Transmission for this project.

As far as modifications go, I plan on building the engine up, toss on a set of headers and maybe open up the intake. The intake on Diesels is pretty unrestricted as it is. There will be no EGR on this ride. I plan on installing an electric vacuum pump to handle the vacuum load so that should not be an issue.

I just need to find someone to do the welding for me, that is one skill I have yet to acquire.

Down the road I may drop in a 6.5 or 6.6 turbo, I have the wife's blessing, I just have to spread it out so the money thing isn't an issue.
Thanks, please let me know if you have anymore information.

:alchi:

I'm looking for a 472/500 and you want to replace one with a diesel :(

Keep the EGR. It improves fuel economy during part throttle cruise. Injection timing is calculated assuming a working EGR.

Keep the EGR. It improves fuel economy during part throttle cruise. Injection timing is calculated assuming a working EGR.

I believe what you're saying applies to gas engines. With the older GM diesels, injection timing was all mechanical. On these diesels, EGR did clean up the exhaust a little, but it didn't take long for it to clog up the intake and make it run dirtier than not having it in the first place. I didn't notice any fuel economy difference when I removed the EGR on my '82 6.2L diesel and it sure smoked less after removing it and cleaning all the gunk that had restricted the intake.

As far as modifications go, I plan on building the engine up, toss on a set of headers and maybe open up the intake. The intake on Diesels is pretty unrestricted as it is. There will be no EGR on this ride. I plan on installing an electric vacuum pump to handle the vacuum load so that should not be an issue.



You can also increase power by matching the runners on the intake manifold to the heads. Diesels need to breath and anything you can do to help it increases power. With the modifications I mentioned in the last several posts as well as this one, it shouldn't be too hard to make 170 hp (about 80% of what you would get from a turbo at sea level).

With proper gearing (3.08 or 3.54) and a 700-R4 transmission, you can expect 25 mpg on the highway at speeds under 65 mph.

IMO you'd be better off finding a smaller car or a bigger diesel.

A little transmission fluid in the right places can help keep things clean. Injection pump timing is extremely critical and I'd worry about scuffing the piston skirts without the factory designed EGR. Plenty of the 350 diesels met the end with oval shaped cylinder bores. Maybe they also experienced gummed up EGR systems and were not cleaned out in a timely manner.

Back at the ranch. I dunno if there was ever a long tail 700R4. Something to check into. If not, you will somehow need a longer driveshaft. Maybe a 2 piece from a commercial chassis limo or hearse would work. You would need a place to mount the center bearing and could cut the front drivechaft to fit. The TH-400 uses a different yoke than the 700R4 so you would need a fabricated front shaft.
IIRC those cars has either 2.93 or 3.15 axle ratios. Either would be in the low 2's with the overdrive.