Diesel Swap questions (Gas mileage, not power)

[chevy72blu]

It would likely be cheaper to do an LSX swap to achieve your 20+ MPG goals. There is actually a section just for them on the forum in the Engine and Drivetrain section.

Of course, there is something to be said for doing things differently. If cool factor is what you are after, I love the 6.2. For economy, LSX all the way.

[Andrew S]

If you haven't already, spend some time over at www.4btswaps.com. They have more information than anywhere else I've found about diesel swaps of all kinds, not just the 4BT. 6BT, Isuzu, GM 6.5/6.2, you name it, it's probably been discussed there. Best of luck, whatever your decision ends up being.

[special-K]

How cheap can you get an LSX for? And,don't you need a computer,harness,special headers,mounts. What do guys spend on swaps? I think they are a great solution,but I have to admit I'd have to think long and hard about taking truck perfection and adding a computer to it. Simple is good in this modern world.

[Lemield]

Originally Posted by special-K

His name is Nathan Koch. I'm acquainted with him by setting up side by side at Carlisle Trucks these past two years. A very sharp and nice guy. His adapters are probably limited to later Jeep transmissions,but who knows? See what he says. My name is Tim.
EDIT: He does mention Willys
www.mercedesdiesel4x4.com

Thanks for the info Tim.

[BiggSixx1970]

An LS engine would be sweet, VERRY sweet.. But I just don't have the know how when it comes to all the computer controlled stuff, wiring harnesses, getting all new gauges, not to mention that would be FAR out of my price range. One of the reasons why I went back in time and bought this pickup to begin with is because I got tired of dickin' around with electronics going bad on my past few vehicles (Keep in mind I'm a poor college student in my early twenties, so all of the cars i bought were cars from the 90's off craigslist, those are just my experiences). To me, diesel engines have always looked to be WAAAAAY more reliable than gas (except for maybe starting it in the winter)

I also understand fuel injection and electronic ignition are a great, there is a reason why they switched from carburetors to EFI. An LS swap would be GREEEEEEAT, don't get me wrong. It will be considerably easier for me to get a hold of a 6.2 Diesel, than an LS. If i put an LS in, I'm going to be too busy burning the tires off to get decent MPG. I also cannot run an LS motor on vegetable oil if i choose to do so

The reason I started this thread were to determine if dropping a 6.2 Detroit in it would be as easy as say throwing a small block in during the weekend? What transmission would be ideal for gas mileage? and what rear end would be ideal for fuel economy? Would putting a 6.2 in it be as easy as pulling the old engine out, putting in new motor mounts, bolting the diesel to my existing transmission, connecting a battery, fuel lines, a few wires, and draining the gas out of my take and replacing it with diesel?

[special-K]

Yes,it's that easy...pretty much. You will need a proper fuel/water separator,which would come with the engine. You would need a big block radiator. If the diesel wasn't out of a manual truck you'd need the flywheel and clutch. The throttle is cable operated,you would need to get that from a donor or make something up using 71/72 peddle assembly. Naturally,it won't go like swapping out with what it came with,or even going to V8 gas. But,it will phsically drip right in,mate to your transmission,and just require some simple adaptations for things such as throttle,hooking up a wire to the I/P,and a way to control the glow plugs. The best way is to get a donor vehicle or just know you are getting everything involved with the engine,as with any swap.

If you're going to get into modern computerized stuff,might as well consider a DuraMax. The whole point of swapping a 6.2 into these trucks is pure simplicity and cheap to do. You "will" get your return on fuel savings considering you'll easily use "1/2" as much fuel. If it costs $75-80 to fill your truck you're saving $37.50-40 a tank by the use you get from it. That adds up fast.

[BiggSixx1970]

Aha! Yes, this is what I'm looking for special-K. A donor vehicle you say? so you're saying if I went to pick'n pull, found an old Chevy diesel I could snag all the wiring, gauges, and whatever controls a diesel and just mount it in my truck? Is there any way I can find out what sort of components I should be looking for?

I really appreciate the help, I am a total novice, the is my first project so I'm just diving in head first with a few bucks at a time, some wrenches, and a whole lot of internet at my disposal. I am pretty close with the O'Reilly's that's two blocks from where I live so rental tools are at my disposal and I got a buddy with a engine hoist.

I am trying to get everything I need hashed out before I go to buy an engine for transplant this upcoming spring.

In the mean time.. I did find this little cherry on craigslist lol. I'm a bartender, tomorrow is a game day.. If I make $200 cash in tips I might throw this baby in haha
http://kansascity.craigslist.org/pts/3225907399.html

(Pick'n pull is the name of a huge car scrap yard that's full of donor cars in my area)

[Edahall]

If you do end up going with the 6.2L diesel, there are several things you can do so that it gets very high fuel economy (like nearly 30 mpg).

1. 3.08 gears
2. Overdrive transmission. NV4500 would be the best choice.
3. 30x9.50 or 235/75/15 tires
4. Good set of injectors with equal pop pressures
5. Exhaust headers and free flowing exhaust
6. Heads with small precombustion chambers. Note: the older heads had smaller precombustion chambers.
7. J code intake manifold (no EGR pedestal)

Stay away from the 6.5L diesel or adding a turbo charger. A turbo is great for more pulling power but usually is a detriment to solo fuel economy.

[Pillow]

Subbed!

I will be picking up a 6.2 military repower tonight to go into the '71 to replace the tired stock 350. Right now the 350 is going into a T-5 which has IMO the perfect gearing for a 6.2 without over revving the motor... Since diesels do not like being revved much this is a big deal for highway cruising.

... More to come, but I have been pondering this for years! And yes the 6.2 can take alternative fuels. And probably an EMP attack as well! LOL

FWIW I have a '99 Suburban with the 6.5TD and really like it, modified. It gets 20 at an easy 55-60... Normal commuting is around 16. Towing 6000lbs is about 13.5. 3.73 gears.

More to come!

[Pillow]

Add: DBears installation since he was referred to earlier.

http://67-72chevytrucks.com/vboard/s...d.php?t=425168

[1972RedNeck]

I have looked into a lot of diesel swaps for my K20. My first preference would be a 12 valve Cummins for power. If I can ever get the money to do a swap though, I will go with a 4BD 1T Isuzu. From what I have read it is a superior engine to the 4BT Cummins and can get a little better mileage.

[69 4by]

My opinion if you have to have a diesel is find a wrecked 89-93 dodge cummins. Then you have an engine, trans, rear end and all the other good stuff you need for a swap. The old 12 valve can get up to 25mpg or so with some simple mods. Just my 2 cents, Good luck

[Edahall]

Originally Posted by 69 4by

My opinion if you have to have a diesel is find a wrecked 89-93 dodge cummins. Then you have an engine, trans, rear end and all the other good stuff you need for a swap. The old 12 valve can get up to 25mpg or so with some simple mods. Just my 2 cents, Good luck

I agree. I used to have a Suburban with a 6.2 diesel and it was alright. However, I upgraded to a Suburban with the 6bt Cummins and 6 speed manual and what a huge difference. The Cummins has much more power and gets just as good fuel mileage.