Considering diesel conversion; what should I expect?

[Crunch]

Since purchasing my truck I've been toying with the idea of a diesel conversion on a 1960's era passenger car. I've been paying heavy on my `03, and am now at the point where I can start looking for a suitable candidate. My plan is to convert an old Chrysler Imperial (preferred), Caddy or Lincoln into a diesel "family limo".



I'm reasonably mechanical, but will probably farm out a lot of the body work, and perhaps some engine work. Money is not a big problem, and I am hoping for a very factory/professional look so I'm not concerned about doing all the work myself. But I don't know what to expect once I start, and am looking for input.



Here are the main questions I have:



* What modifications will I need to make in order to fit the Cummins in an older car? I already figure it will be taller, and am planning on modifying the hood to accomodate it.



* To what extent can the high-end electonic components of the engine be adapted to a low-tech vechicle?



* Will I be able to use the transmission/rear end from the car, or should I plan on a different transmission, drive shaft and rear end?



* To what extent will Cummins help me tune the engine for maximum performance? I'd drive up to Yankee territory if they would do it, but will settle for the performance boxes if they won't.



* Since the car will weigh about 40% less than the truck, what kind of fuel economy can I expect from this type of conversion?



* Is it a good idea to replace the existing suspension/hubs/brakes with modern equipment that performs better, or stick with the original equipment?



* What are the unexpected problems I might run in to?



* Am I crazy for even contemplating this?



Thanks for any help provided. There's just something about those old tuna boat cars that I love, and have always thought the luxury aspects of those cars are far better than what you get in pretty much any "luxury car" on the market today. Riding in the back of an 60s-era Imperial was just like sitting on a big, overstuffed couch.

 

[DPinkston]

I'm kinda new to all this diesel stuff, and I have just about reached mid point in my Ford Cummins conversion so I'm no expert, but I would consider a 4BT if I were you. It would be much easier to stuff into a car, and it would weigh about 25% less than the 6BT which would be easier on the suspension. Some of those big old barges will weigh close to 5,000 lbs. I don't think you'll have any problems finding adapters.

Danny

 

[DPelletier]

OK,



- motor mounts, firewall interference/rad issues (prob need to use elec. fan), hood clearance are your main modification issues



- You should be able to carry over any necessary elec. from a donor truck, but why not just use a 12V?



- If you get a big block car with a 727 transmission, it should handle the power though you may want a different converter and a shift kit to firm it up some. rear end should be OK on such a car too.



- Cummins offered an "uprate kit" for the earlier motors (605 ft lbs. )



- probably about 5 mpg more depending on axle ratio



- If the car doesn't have front disk brakes, you'll want to add them. You'll also need HD coils and good shocks.



- Yes, you will have unexpected problems!



- Yes, you are crazy, but crazy can be good sometimes



Dave

 

[Headshot zod]

here's some questions... .



how much taller is a cummins vs a big block?



how much heavier is a cummins vs a big block?



can the front end handle that much weight? I only say that since I think they have said 1st gens have weak front ends. I can't imagine torsion bars and a cummins.



I have often thought of cool diesel repowers.



A 1967 barracuda notchback with a circa 1985 5cyl turbo diesel benz motor would be pretty hot. Or with the new jeep liberty diesel would be even cooler. If you could find a mid 80's bmw turbo diesel motor that would rock to.



But with a cummins... ... maybe if you could find a 40-50's car that used leaf springs all around might be an easier start. At least you could beef up the front easier.



a 1970 imperial would rock with a cummins... ya know... there might be enough room to put a straight axle in the front. just run it w/o 4 wheel drive



jmho.

 

[Crunch]

here's some questions... .

how much taller is a cummins vs a big block?

how much heavier is a cummins vs a big block?

And good questions, they are. Does anyone know the specs on a Cummins diesel, and has it changed since the late 1990s? Specificly, how tall, how wide, how deep and how much does it weigh?

can the front end handle that much weight? I only say that since I think they have said 1st gens have weak front ends. I can't imagine torsion bars and a cummins.

I've already concluded that the suspension will have to be seriously beefed up, if for no other reason than handling. Others have also suggested bigger coil springs. If I go ahead with this I would do it with the intent of doing it right, and not just getting it to work. If it came to it, I could see using the hubs/rotors and suspension from a truck and raise the profile of the car a bit. I can live with 17" wheels on a diesel Lincoln or Imperial, if it drove well. My concern is that the weight of the engine and front end will really inhibit steering.

A 1967 barracuda notchback with a circa 1985 5cyl turbo diesel benz motor would be pretty hot. Or with the new jeep liberty diesel would be even cooler. If you could find a mid 80's bmw turbo diesel motor that would rock to.

Not a fan of the Liberty, but one of the standard fantasies my friends and I had in high school was dropping a V8 into a VW Bug. Looking back, I bet a Cummins would have worked just as well. Can't see getting the engine in the front half of the Cuda, though. I think the back half is just too light to handle it once it's moving.

But with a cummins... ... maybe if you could find a 40-50's car that used leaf springs all around might be an easier start. At least you could beef up the front easier.

If I went with a car that old I'd go with one of the top end luxury cars for sure. Too bad I can't afford a Dusenberg! That would be an awsome diesel.

 

[SAvery]

The 4BT with adapters is about 700lbs. The 6BT is about 950-1000lbs. The height is averaging 33" depending on configuration. The front end would be looking like a lowrider with a 6BT in it. Better beef up the rear end to a 9". I would almost seriously consider adding airbag suspension to help the front. If you could get that thing to bounce with a 6BT you'd be the man. YOu probably are going to have to cut a hole in the hood to fit a B series engine. I would (and I know this is blasphemy) suggest and old 6. 5 Chebby diesel because the V configuration would eliminate the height issue.

 

[towner]

Find the right car

Buy the vehicle where the engine will fit don't buy a car and make the engine fit... . I spent alot of time with tape measures at car shows,wrecking yards and anywhere I could find old rigs that I like... . I ended up with the dash and body from the original rig but you'd never know it just looking at it.

https://www.turbodieselregister.com/...ighlight=apache



remember you'll have to have a radiator,intercooler and A/C condensor out front..... try to find a vehicle body style that was also used as a Limo or Hearse thay will have heavier duty suspension systems... . seach around on Air Ride http://www.ridetech.com/ it will be easier to use an airbag assist than try and find the right spring rate... getting big disc brakes are easy there alot of companies out there.



As far as donor motors go stick with a 94-98 12 valve motor. too easy to modfy and the most reliable... plan on getting a good auto trans right away (ATS in SLC)they're the weak link with the cummins. The rear end I'd look at would be a semi-float dana 60 because there's so many axle manufacturers it would be easy to get an axle to match the pattern of the front.