Questions about a Gas to Diesel conversion for a '72

[Gadoozle]

Hi Everyone,

I'm looking at converting my '72 Chevy with a 350 to a diesel for the sake of fuel economy and because the sound of a diesel is amazing. I'm not overly interested in power, but don't want a weak engine either. So, I have several questions I was hoping you fellows here on the forum could help me with.

-What kind of engine would be good for a simpler conversion?

-About how much would such a conversion cost?

-What would be the steps to converting to diesel?

Thanks!

[67_C-30]

The cheapest, easiest conversion would be a 6.2 or 6.5 diesel. Without a turbo, they are not the all that powerful, but with a turbo they'll run similiar your 350 but will get 20+ MPG in a 1/2 ton pickup. I put a 6.5 turbo on a low mileage miltary takeout (they came in HumVee's, M1008, M1009 miltary Chevy trucks) a '67 C-30 dually. Low mileage Miltary HumVee takeout engines range between $400 - $1000, and it will bolt your existing transmission. You will need big block motor mounts, but otherwise they are direct bolt in. The only thing you have to do with the fuel system is run a return line to the tank. Your '72 probably already has one, but my '67 didn't. Best of all,there is no computer, or electronics. They have mechanical injection pumps and it is as simple as running your coil wire to the IP, and it will run. Here's my build thread and some pics.

http://67-72chevytrucks.com/vboard/s...d.php?t=254096

[67_C-30]

Oh, and I think you'll find that it sounds awesome!

YouTube - ‪IT LIVES! 6.2L Turbo...

[Gadoozle]

Thanks for all of your information! I will look into your build thread and will learn a lot from it!

[cucvzuz]

4bt cummins all the way. 20+ mpg and plenty of power they came in bread trucks with a th400 behind them. I have a 4l80e behind mine i can do 90+ on the highway at 20mpg. with the 4bt there is no cutting of anything, mine just dropped in, all i had to do is build motor mounts.

[1972RedNeck]

This is a very bad idea. Do not use it.

I think a 5.7 Oldsmobile diesel would bolt in. It would be a gutless wonder. The one my ant had got 12 MPG.

[1972RedNeck]

I meant aunt.

[The Youngen]

I am literally getting ready to start this conversation in a week or two. We will hopefully be picking up a 85 military blazer next week. I decided to do a 6.2 conversation. From my research, as previously stated, all you really have to do is use big block mounts and your good. After tearing apart my 71, i found it already had a unused return line so you should be good there. Im planning on mating it with a manual 5 speed. the military trucks were 4wd with 3.08 gears, turbo 400 and the 6.2. they got around 20 on the highway. i figure with a od and a manual, i can get 25 solid. Plus as stated, they are cheap to get. Problem with the cummins is that they cost alot and, at least in my area, finding those exact bread trucks is hard. 6.2 is cheap, efficient and easy. Just my 2 cents. Upfront im looking at $2,000 for the swap but thats assuming i dont do anything with remains of the blazer.

Sorry for the long explanation but i tried to do my research and i decided on the 6.2.

http://67-72chevytrucks.com/vboard/s...d.php?t=469045
A thread i started a couple weeks ago.

[mr48chev]

That should make a good rig to hit the road with and not break the bank in the process.

I bid on a couple of bread trucks with the 4 bt in them and good ones go higher than my budget allows for.

[67_C-30]

I always wanted to put a 4BT in one of these trucks until I helped a friend put on in a Jeep. The 4BT was too loud, crude, and vibrated way too bad for my taste. The 6.2 is quieter and has a way smoother power delivery. The 6.2 is OK in stock, form but is really a fun engine to drive with a turbo. Even with a turbo, the HP numbers aren't that high at around 200, they will make a legitimate 400 ft lbs RWTQ with just a little tweaking. The 6.2/6.5 weighs less than a BBC and will get 20+ MPG easily. My Miltary Blazer gets around 21 in town with 33 X 12.50's and weighs 5200#, much more than a 2WD 67-72 truck.

I'm not knocking the 4BT. It is great engine, and will take more abuse than a 6.2 ever will. It just wasn't my cup of tea.

[Heavy Evy]

hmmm this thread has me thinking....
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[Gadoozle]

I know doesn't it?

[The Youngen]

Simply,
6.2= cheap conversation, simple conversation, simple way to get 25 mpg, can have most 6.5 parts bolted on for more power, stock hp and torque equals a stock 305.

[Heavy Evy]

im thinking 6.2/6.5 swap in my 71 c20 making it the tow/long haul rig i always wanted it to be. everyone tells me to go with a 24v cummins but im not a fan of half breeds. keep your gm all gm right ?
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[67_C-30]

Originally Posted by Heavy Evy

im thinking 6.2/6.5 swap in my 71 c20 making it the tow/long haul rig i always wanted it to be. everyone tells me to go with a 24v cummins but im not a fan of half breeds. keep your gm all gm right ?
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As much of a fan as I am of the 6.2, I would go with the 5.9 Cummins in a long haul truck. The 6.2/6.5 are efficient engines, but they really need a turbo to do any pulling. If you are going to be a single car trailer or something like that, they'll do fine, but if you are going to be pulling heavy loads the Cummins is a much better option.

If did go with a Cummins, it would be a 12V though. They are mechanical engines with no computers or electronics, and are simple like the 6.2's.

[Heavy Evy]

sorry i meant long haul as in road trips. i wont be towing anything bigger than a single car or boat trailer but thats only if i do tow. i need to get some prices on 6.2/6.5's in my neck of the woods to see what im up against.
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[ZombieWeinerDog]

7.3l powerstroke! best diesel ever made

[1968CHEVYC10]

Yeah if you don't need huge power I def recommend the 6.2, I picked one up off craigs for $200, and should be finished with the swap on monday.

[special-K]

Originally Posted by Heavy Evy

...everyone tells me to go with a 24v cummins but im not a fan of half breeds. keep your gm all gm right ?

Then,I guess Dodges are half breeds cuz it ain't their motor either . Same with Fords. Ford don't make no diesel. They run Internationals (Navistar).I look at it like big trucks when it comes to diesel power. You could have a Ford L-type with a Detroit Diesel built by GM. Allison transmissions are all across the board. You custom order a drivetrain to suit yourself.

I've seen some Isuzu NPR conversions and I wonder why these aren't popular. Lord knows those trucks are all over the place and aging.

I put a 3" exhaust with 6" round Magnaflows on my 6.2 Suburban and I felt a noticeable increase in power. I want to built a double stacked air cleaner with dual fresh air intakes on my 6.2 Jimmy,along with 3" pipes.

[67_C-30]

Originally Posted by special-K

Then,I guess Dodges are half breeds cuz it ain't their motor either . Same with Fords. Ford don't make no diesel. They run Internationals (Navistar).I look at it like big trucks when it comes to diesel power. You could have a Ford L-type with a Detroit Diesel built by GM. Allison transmissions are all across the board. You custom order a drivetrain to suit yourself.

I've seen some Isuzu NPR conversions and I wonder why these aren't popular. Lord knows those trucks are all over the place and aging.

I put a 3" exhaust with 6" round Magnaflows on my 6.2 Suburban and I felt a noticeable increase in power. I want to built a double stacked air cleaner with dual fresh air intakes on my 6.2 Jimmy,along with 3" pipes.

If you are going to stay naaturally aspirated, Hummer headers are a nice addition. They are tight fit on a truck, but they will work. It would be cool t see some of them on a 67-72 too.

[ZombieWeinerDog]

Originally Posted by special-K

Then,I guess Dodges are half breeds cuz it ain't their motor either . Same with Fords. Ford don't make no diesel. They run Internationals (Navistar).I look at it like big trucks when it comes to diesel power. You could have a Ford L-type with a Detroit Diesel built by GM. Allison transmissions are all across the board. You custom order a drivetrain to suit yourself.

I've seen some Isuzu NPR conversions and I wonder why these aren't popular. Lord knows those trucks are all over the place and aging.

I put a 3" exhaust with 6" round Magnaflows on my 6.2 Suburban and I felt a noticeable increase in power. I want to built a double stacked air cleaner with dual fresh air intakes on my 6.2 Jimmy,along with 3" pipes.

the new ford 6.7 is made in house.

if i was doing a diesel conversion today, i would do either a 12 valve or a new 6.7 iron-graphite block thats nice and light. matched to a powerglide from a 6.0 ford, it can handle more power than the allison.(allisons are very overrated.)

[C-10 simplex]

Originally Posted by 67_C-30

The cheapest, easiest conversion would be a 6.2 or 6.5 diesel. Without a turbo, they are not the all that powerful, but with a turbo they'll run similiar your 350 but will get 20+ MPG in a 1/2 ton pickup. I put a 6.5 turbo on a low mileage miltary takeout (they came in HumVee's, M1008, M1009 miltary Chevy trucks) a '67 C-30 dually. Low mileage Miltary HumVee takeout engines range between $400 - $1000, and it will bolt your existing transmission. You will need big block motor mounts, but otherwise they are direct bolt in. The only thing you have to do with the fuel system is run a return line to the tank. Your '72 probably already has one, but my '67 didn't. Best of all,there is no computer, or electronics. They have mechanical injection pumps and it is as simple as running your coil wire to the IP, and it will run. Here's my build thread and some pics.

http://67-72chevytrucks.com/vboard/s...d.php?t=254096

That's great; But where do you get these takeout engines?

Also if you have stock exhaust on the truck, will the manifolds from the diesel bolt right up?

[67_C-30]

Originally Posted by C-10 simplex

That's great; But where do you get these takeout engines?

Also if you have stock exhaust on the truck, will the manifolds from the diesel bolt right up?

Ted's Trucks n Stuff has them. He has sold hundreds on them. They are a little higher now than a couple of years ago, but the good thing is that he puts every engine on a test stand, checks compression, runs them up to temperature and makes sure they are good running engines. This eliminates the possibilty of getting a bad one with a blown head gasket, cracked head, knocking, smoking, broke off starter bolts, etc. Sometimes other guys buy a bunch from miltary auctions, and sell them for $300 - $500 each. There show on ebay a lot. I bought mine from someone that had a video of it running for $400.

The exhaust would needs a little modifying to fit I would think. I put a turbo on mine with single exhaust replacing a 292 L6 with exhaust on the other side of the truck, so I knew I was going to being changing my whole exhaust system anyway.

http://cgi.ebay.com/ebaymotors/ws/eB...m=&refid=store

[Heavy Evy]

Originally Posted by special-K

Then,I guess Dodges are half breeds cuz it ain't their motor either . Same with Fords. Ford don't make no diesel. They run Internationals (Navistar).I look at it like big trucks when it comes to diesel power. You could have a Ford L-type with a Detroit Diesel built by GM. Allison transmissions are all across the board. You custom order a drivetrain to suit yourself.

I've seen some Isuzu NPR conversions and I wonder why these aren't popular. Lord knows those trucks are all over the place and aging.

I put a 3" exhaust with 6" round Magnaflows on my 6.2 Suburban and I felt a noticeable increase in power. I want to built a double stacked air cleaner with dual fresh air intakes on my 6.2 Jimmy,along with 3" pipes.

Too each there own but I'll keep my chev all chev. I love how that 6.2 sounds in your 67 C30 man! Defenitly got me thinking about a swap.

[1972K20]

Is there much difference between a 6.2 and 6.5?