Has nobody considered a diesel swap?

[jwreding]

I was just curious if anybody has done or has maybe thought about swapping a diesel engine into their Clipper.  This summer I plan to start my conversion to a 6.5TD GM motor.  Whoever decided to put the 400sbc in these was not having their best engineering day.  A small block engine should never be asked to push any 9,000lb. vehicle down the road and through the mountains.  I first considered a 454 big block chevy but although I would have much better torque for hill climbing and such, I'd still only be getting 5-6 mpg at best.  The diesel just seems like the obvious choice.  6.5 engines in vans and trucks can get almost 25mpg highway unloaded, so I figure a fully loaded Clipper might manage 15-17 with the proper cruising RPMs.  Plus, I'd have the chance to run on biodiesel whenever possible, and maybe someday start making my own free veggie diesel.

The concept doesn't seem to hard, it's the sweat equity that will be the major drawback.  First of all, it's going to be extremely hard to find a 6.5 drivetrain out of a Chevy van of the proper year.  They were only available from 1994 to I think 1998 in the vans.  If I can't find one out of a van I'll have to still find the top-mounted turbo since the regular truck turbo would definitely not squeeze into the tiny engine compartment.  From there it's on to fuel plumbing and installing the millions of sensors and wires that a diesel engine requires.  I'll either find a replacement tank or give the existing one an extremely good flush and just use it.  I'll have to separate the generator fuel supply, or maybe just find a diesel generator that will fit.  The final hurdle would be figuring out how to reduce the final gear ratio to keep it from turning such high RPM on the highway that gas motors require.  I'm not sure what ratio of rear end mine has, but I'm going to assume 4.10, which would put me at well over 3,000 RPM at 65MPH, which is insanely high for a diesel and not good for it in general.  I'm debating as to whether I should regear the axle, install a Gear Vendors OD unit, or (as a last resort) cross my fingers and swap in an overdrive transmission, hoping that it will last for more than 1000 miles.

This seems like such a good idea on paper but we'll see how things actually go.  I plan on doing a full writeup with many pictures in case anyone else has been wanting to do this and is interested in how it goes along.

[Horst]

Have you thought/calculated how many miles you'll have to drive before you get your money back on this investment?
What about staying with the 400 and simply installing a Gear Vendors unit? You may get as much as 2 miles per gallon more, and have that 2.5 gear for the hills, and that 1.5 for the steep stuff
Seems to me you'll have to drive MANY miles to cover the cost and energy spent doing  a diesel conversion - and 15-17?? - I'm not sure I'd belive that.......maybe with a gear splitter in addition to the diesel - but now you are talking some serious money and work.........

Might even (gasp!!) be worth looking into selling the Clipper and buying a diesel motorhome, or a small bus and build your own RV.

I did this cost assessment a few years ago when considering simply installing a Gear Vendors unit - and decided against it - and that was only a $3000 investment.
If gas goes to $5/gal - well then, that's another story..................

[jwreding]

Well mileage isn't the #1 main reason for doing the swap, and I can't just keep the 400 because I don't have one.  It threw a rod 12 years ago and had to be replaced with a 350 (I was only 9 years old at the time so I couldn't really do anything about it nor did I know what a 350 or 400 even was).  Now, the 350 is pretty much junk after all these years of sitting.  I just think it would be interesting to try to accomplish this and will be really proud when it's finally done.  It would truly be a unique vehicle, being as Clippers are already rare and none that I know of have a diesel engine.  No way would I sell the Clipper, if it weren't for her then we wouldn't even have a motor home.  We don't really have a need or use for one but they're so neat I can't bear to get rid of it.  Plus, not having a dire need to use it would allow for plenty of time to work on this project.

I know it will take years upon years of driving to make up for the cost and sweat factor of doing this, but it seems like such a neat idea I can't bear to give it the boot, especially when a new engine is in order already.

[jeffphilbrook]

I've got a '77 dodge with 440 and think a cummins 5.9 would be a real performer--and get better than 6 mpg. How did your GM swap go? Jeff Philbrook

[Rodney]

intresing idea.
one concern I would want to have solved before spending the money is cooling. would a large enough radiator fit in the limited area?
and if the engine you are considering has inter-cooler for a turbo is there room for all of that?
add a trans cooler and if you are planning on A/C the small space is getting smaller and smaller.
then the limited area under the dog house?
just thinking out loud.
keep us posted in this project.
Rodney

[JerryT]

The 5.9 cummins has a little brother the 3.9, same engine minus two holes, bread and chip trucks use them, the 2006 motors are rated at 170 hp and 410 torque. I was told that the older ones can have the power turned up also. The measurements seem to be very close to the dodge engine compartment, the 5.9 would be too long. I may start collecting parts for this kind of swap if I can confirm that the 3.9 will tote the load ok. I have the 440 now and it's like driving a sports car with a bathroom, lots of power, I like that just not the mpg.
Jerry