GM 6.2 diesel swap questions (10 Viewers)

[rchalmers3]

rchalmers3, I will do some research o the programmable 6.5. I was taught to work on modern cars and diagnose problems with obd systems, but it's been some time and many of those skills have left me. Are they as plug and play friendly as say the vortec system? If so I might just look into that at my #1 swap on the list.

To keep the cost within reason, I do not recommend starting with a 6.2L and trying to make it into a 6.5L by adding a turbo and the drive accessory pieces. Yes the 6.2L with the lower compression will readily accept a turbo, but why do all the expensive after rigging? Shoot, you practically have to buy 2 motors to make one! That is counter to your goals of dropping in an affordable, ready unit that is engineered to work as is.

Your specific questions about tweaking the 6.5L can be answered elsewhere: Diesel Place - Duramax Diesel Discussion Forums If you had training and experience in feedback, closed loop systems, you have everything you need to fully implement a 6.5L into your project. The players are the same as gassers, and performance technology exists to dial in the performance you desire.

Regarding the straight 6 Isuzu, I have driven a land cruiser with the 6bt. It may produce great torque and power, but it is also noisy. I cannot answer if it is too much motor, my buddy drives his tamely and it's holding together.

You and your wife will probably be best served if you swap in a diesel that does not detract from the daily experience of driving. If it is noisy or vibration prone, the project won't be a complete success. Maybe you should reach out to fellow mud members and drive a few different swaps for a comparison???

Rick

 

[rtarh2o]

Check out my thread on this topic if you haven't already.

https://forum.ih8mud.com/diesel-tech-...on-begins.html

This might answer some of your questions.
From what I have read the 6.2 with the banks turbo actually puts out more power than the 6.5 turbo, not sure how or why but that is what I read.
Also, there is a clearance problem with the shock tower with the 6.5 that I have heard about also.
The serpentine belt was also available on the 6.2's, if I were doing it again I would definitely go that route.

Feel free to ask any questions, I have sold the vehicle to buy a Mercedes G350 TD, one of only 3 in the country, I couldn't pass it up otherwise I would still be driving the 6.2 Cruiser.

Rusty

 

[Irish52084]

I'm definitely warming to the idea of the 6.5 turbo. Complete low mileage trucks are readily available in my area. I think I'll buy a complete truck when I decide to do the swap, that way I'll have the accessories, hydraboost system and larger master cylinder, serpentine belt system, a/c condenser and pump etc...

rtarh2o, you're build thread is a great resource and actually one of the major reasons I started thinking about the 6.2 Detroit. If I go with a 6.5 turbo in an 80, how hard is modifying the shock tower to make it fit?

I will definitely line the entire interior of the truck with dynamat extreme or something similar to keep road and engine noise down. I'm deep into a total frame of rebuild and custom fj40 with my dad at the moment so I'll get some real world idea of how lining the vehicle helps with noise and vibration in the near future.

 

[Irish52084]

torslinning, was your truck listed on craigslist? Did you have a few videos of it running as well? If that was your truck, it was very nice and if I knew what I know now I would have bought it in a heartbeat.

 

[Irish52084]

I currently drive one of the slowest vehicles ever as my work commuter. A 1993 Honda civic cx is hugely powerful, maybe 70 hp. I dont need my diesel commuter to be powerful or fast, I'm used to being passed everywhere I go. At least if I'm driving a cruiser every guy with a coffee can muffler and a honda wont pull up to me at a light and wanna race.

 

[rtarh2o]

Not sure about the shock tower mod I just remember talking with someone who did a 6.5 conversion (I think he is somewhere on my build thread) and said he had to modify the shock tower, may not be a big deal.
I think a lot of it will depend upon where you live, I live in the flatlands of east Texas so the 6.2 had plenty of power for me, more than the stock Toyota did, however at altitude you need the turbo or if you plan to tow anything, otherwise I say just stick with the simplicity of the N/A engine and enjoy it.

Rusty

 

[Irish52084]

I was wondering about running a non turbo at altitude. I live in western Washington and everything is on a hill, and I drive over mountain passes probably 10+ times a year. Looks like a6.5 turbo if the shock mount issue isn't a big deal. If the shock tower modifications seem like too much of a hassle, I guess I'll turbo the 6.2 or rethink my engine choices.

 

[torfab]

torslinning, was your truck listed on craigslist? Did you have a few videos of it running as well? If that was your truck, it was very nice and if I knew what I know now I would have bought it in a heartbeat.

Yep, that was mine. I sold it to a guy in Colorado just 2 weeks ago, and I miss it to pieces. I run a little Toyota shop out of my house in Lynnwood, and I've been thinking about building another one.

10K and I can build one for anyone, I'll even provide the car AND engine, etc.

 

[Irish52084]

torslinning, I would definitely consider having you do a swap. I'd kinda like to do it myself, I hope you wouldn't mind me asking questions on the specifics of your swap.

I was reading another thread here where a fj55 might fit onto an older k5 blazer frame with little modification. if that turns out to be true i might see if a 60 or 80 series could be adapted as well. If the blazer frame and drive train swap is straightforward it seems like the most cost efficient way to swap a 6.2 or 6.5 turbo diesel. The availability of military k5 blazers with rear lockers and low miles is intriguing. I know of a low mileage, 63k miles, military blazer nearby for less than $2000, if mating an fj60/80 body is possible I will almost have to try this out.

 

[jcj_78FJ40]

I have also been looking at swapping in a 6.2 in my 91 FJ80.

Just a note, another difference between the 6.2 and the 6.5 is that the 6.2 injector pumps are $300 compared to $1000 bucks.

I have been looking for a 90-92 DOT truck. I seem them for sale frequently with ~120K to 150K miles on them. They have the updated rocker arms, serpentine belts and a OD transmission (I’m guessing the 460LE). With the 80 series 4.11 gears, an OD transmission is a must.

Although my latest thought is to swap in the entire engine and drive train from a military truck or blazer. These come stock with the turbo 400 (a great transmission but will never work with the 80’s 4.11 gears), NP208 TC, Dana 60 front and a 14 bolt FF rear. The gears are 3.08. Of course I would have to fab and weld the spring buckets and brackets to the military axels.

At this point it’s just an idea that popped into my head. I have no idea if this is feasible or what the width of the military axels are compared with the 80 axels.

Any thoughts comments on this??

 

[Irish52084]

jcj_78FJ40, The military blazers had 3.08 gears, but the trucks had 4.56's or 4.88's if I remember correctly, just something else to consider. If you can find a dot truck with updated rocker arms and serpentine belt it would be the way to go.

As far as overdrive transmissions, I would guess that the 4L60, 4L60E or 700r4 would be the most likely swaps for overdrive transmissions. The 700r4 and 4L60 transmissions are essentially the same transmission, except the 4L60E is electronically controlled.

If you decide to go with the military blazer frame swap, the 700r4 is an easy replacement for the turbo 400. You could probably sell the turbo 400 and buy a 700r for pretty much nothing. If you had the extra cash, an nv4500 or even better, an nv5600 would be pretty easy to install and you would have a 27% over drive and be able to shift your own gears.

 

[Irish52084]

jcj_78FJ40, I almost forgot to mention that there is another thread about an fj55 possibly fitting to a blazer frame with little modification. I'm going to try and get some measurements to see if a 60 or 80 series could also be swapped onto a blazer frame. If this turns out to be a reasonable option I think it is the route I'll take. If I do swap to a blazer frame, I think I will also swap the 6.2 for a 6.5 turbo and change out the turbo 400 for a 700r4 or nv4500. The military blazers had heavier springs and frames as well, a plus for those who like to wheel harder.

 

[Dougal]

Any thoughts comments on this??

Just do a body swap.

 

[jcj_78FJ40]

Thanks for the gearing info on the trucks. That’s pretty high gearing for 6.2/turbo 400.

Also, good point on the swapping the turbo400 for the 700R4. A low mileage turbo 400 probably would be an easy sell.

I will probably keep looking for a later model. I would also like to find a donor vehicle with AC and Cruise Control.

I hope you start a thread if you do the body swap. That is an interesting approach. Good luck on finding an fj55 donor. Maybe a 60 series will also be close.

 

[jhwood]

torslinning swaps...

I'm the guy in CO with Tor's 6.2L swap.

Picked it up from him in Seattle in mid-November. Within 4 hours of seeing the truck, I started the 1500 mile trek back to Denver. Hit a snow storm 20 miles out of Seattle and caught up with it in Wyoming the next night. But old Smokey plowed right through it all with no problems-- and started up (without the block heater, I should add) at ~20 degrees the next morning.

If anyone is considering having Tor do a swap for them, I would highly recommend him. In fact, a friend of mine is thinking of ordering a Torfab Cruiser sometime soon.

As for the 6.2L swap-- I am no expert, but it seems to have plenty of power (with the Banks Turbo) and the mileage is as Tor said -- 18-22 mpg depending on the type of miles.

If anyone in the Denver area wants to see Tor's work -- or even check out the 6.2L conversion for your own project-- feel free to get in touch with me.

 

[Mikesta]

Yep, that was mine. I sold it to a guy in Colorado just 2 weeks ago, and I miss it to pieces. I run a little Toyota shop out of my house in Lynnwood, and I've been thinking about building another one.

10K and I can build one for anyone, I'll even provide the car AND engine, etc.

10K? Thats it? Wow. I guess if you have friends like me to help you do body swaps... its not all that tough.

 

[torfab]

Thanks for the kind words Jim, I really believe the 6.2 or 6.5 is the perfect application for the Cruiser. I'm glad you're happy, and I hope to see it again someday. Will you go to cruise Moab in April/May?

 

[Comet]

Gone to Heaven.

I have been driving an '84 GMC 6.2 Diesel N/A C1500 for the past three years and I love it. The simplicity of ONE wire running the entire works is timeless. I get anywhere from 24-28 mpg. Make sure you use a good lubricity additive because most of the seals in these oil burners don't hold up well to the ultra low sulfur offered today. I have purchased a 1997 LC with 300K on the odometer with the intention of converting the LC as soon as the engine gives up the ghost. I thought the Isuzu was the preferred swap but I am now so happy to know the venerable 6.2 will work. IMHO The diesel page is by far the most informative and suppportive community on the web related to the Detroit Diesel oil burners. Robyn and the gang are truely one of a kind. Best of luck in your conversion.

 

[Dougal]

I found a research paper on the optimser 6500 which measured it's fuel economy.
At best point it used 262g of diesel to produce each kw of shaft power.
This compares with 215g of diesel to produce each kw of shaft power on the Isuzu 4BD1T.

The optimiser is claimed to be 15% more efficient than the old 6.5. That would mean the 6.5 needs around 300g of diesel to produce each kw of shaft power.

Most good petrol engines are more efficient than that.

The research paper is SAE #2007-01-0235 by Tatur, Laermann, Koehler, Tomazic, Holland, Robinson, Dowell and Price.
It looks at ways to make the optimiser 6500 meet future emissions standards.

 

[Thaddeus]

6.2L GM diesel into FJ80 / Turbo crossover pipe

Hello Everyone! I'm a newbie and I hope I am not highjacking the thread. I've been lurking on your site for about 6 months now and I was so impressed I decided I had to join.

I am working on a long-term project, which is now at the mid-point of completion. I have a 1991 FJ80 Land Cruiser, which I plan to convert over to a GM 6.2L diesel in June. Working on it part time, I have rebuilt the diesel engine and converted the Land Cruiser over to hydraulic brakes.

The engine is sitting in a jig I built representing the FJ80’s frame to make it easier to fit, check clearances, and fabricate custom parts if necessary. I modified the output manifold of the turbo to clear the shock tower, and now I am trying to determine the best method to fabricate the crossover for the exhaust.

To avoid suspension and driveline components, I see two options; I can either run the crossover around the front of the engine by the oil pan, similar to the early Banks turbo system, or run it over the adaptor housing between the engine and firewall, similar to the configuration used with the rear mounted turbo.

I am using the Marks adaptor so that I can continue to use the A440F transmission, and I will be relocating it 20mm forward as recommended, so the top of the cylinder heads will clear the firewall.

Any of you who converted an FJ80 to accept a GM 6.2L diesel using the Marks adaptor might know what the clearances are around the lower firewall over the transmission and adaptor housing. The transmission appears to be almost vertically inline with the firewall, and the adaptor would extend it about 72 mm, or 3 in into the engine compartment.

Does this provide enough clearance for a 2 in crossover pipe, or would it require too much modification of the firewall to safely clear the area?

Thanks.