6.5 TD Rear Mount Turbo Question (1 Viewer)

[Arm Auto]

Good day folks, I've got a line on very affordable low mile 6.5TD optimizer that I plan to drop in my 97 Fzj80. I really don't want to commit any space or time discussing the merits of the 6.5. My only question is; do any of you have experience with a swap of the 6.5 with the rear mount turbo? Not the version that has the turbo coming off the side. I'm wondering how much mod is needed to the firewall to accommodate the rear turbo, or if its even possible. Maybe I have to convert to side mount turbo?? Any experience here would be much appreciated. Below is a pic of the rear mount turbo 6.5 that i pulled off another website. Thank you in advance for your real world feedback.

 

[BEE-JAY42]

I really don't want to commit any space or time discussing the merits of the 6.5.

Then you have come to the wrong place my friend . But seriously, I can't offer any help other than to suggest also posting in the 80 series forum as someone there may know. Goodluck.

 

[handcannon]

If you think you may swap the turbo to the right side exhaust manifold you will need to be able to do a lot of modification to be able to do so. There is a difference in manifolds and heads between the center mount turbo and side mount turbo. The center mount turbo heads have the manifold bolts machined into the head at a different angle than the side mount turbo heads, so the intake manifolds do not interchange.

The intake manifold for the side mount turbo will not bolt down to the center mount heads. You can swap the heads from a side mount turbo motor over to the center mount turbo block in order to put the turbo on the side. Also, the block for the center mount turbo has the turbo oil supply machined into the block. If you permanently remove the center mount turbo you will have to figure out a way to cap that oil supply, or figure out how to use it for the side mount turbo supply.

I have no experience with swapping a center mount turbo over to any vehicle. I just know that heads will have to be swapped to change from center to side mount turbo.

Don

 

[Arm Auto]

If you think you may swap the turbo to the right side exhaust manifold you will need to be able to do a lot of modification to be able to do so. There is a difference in manifolds and heads between the center mount turbo and side mount turbo. The center mount turbo heads have the manifold bolts machined into the head at a different angle than the side mount turbo heads, so the intake manifolds do not interchange.

The intake manifold for the side mount turbo will not bolt down to the center mount heads. You can swap the heads from a side mount turbo motor over to the center mount turbo block in order to put the turbo on the side. Also, the block for the center mount turbo has the turbo oil supply machined into the block. If you permanently remove the center mount turbo you will have to figure out a way to cap that oil supply, or figure out how to use it for the side mount turbo supply.

I have no experience with swapping a center mount turbo over to any vehicle. I just know that heads will have to be swapped to change from center to side mount turbo.

Don

Thanks Don,
That helps tremendously and is what i was thinking would need to be done. It almost sounds like trying to convert an 6.5 Optimizer to side mount turbo isn't worth the hassle? But the jury is still out for me on that and I haven't given up hope yet. I'm hoping to dig around on this forum more later to see if I can find anyone with specific experience with the rear mount turbo 6.5 swaps. Hopefully someone will stumble upon this thread that has experience
For what it is worth, I am midway through a similar conversion on a 60 series. On that rig I'm hoping to just do some firewall mods and slip the same type motor in there.
I'll be sure to document with pics and post when it is done. It would be great to have a nice answer to this as the 6.5 rear mount turbos are good motors and plentiful.
Cheers!

 

[handcannon]

Using a center mount turbo depends a lot on how much space in the engine compartment you have. I'm not at all familiar with the FZJ80. Did it come originally with an inline 6? If so, it might have enough of a stock indent in the firewall for the I-6 to be able to use the center mount turbo. But, that is pure speculation on my part.

The GM side mount turbo's are known for not being the best match for the 6.5, using today's technology. I'm guessing the center mount is the same. With the center mount you are stuck with the GM turbo. With the side mount several other turbo's have been proven to be better. Which turbo to use depends on what your end use will be, towing, hotrodding, fuel mileage, etc.

Go to this web site for GM diesels and read/search the forums for the "GM 6.5 Diesel Engines", and the "6.5 Performance". http://www.thetruckstop.us/forum/

You will find lots of info pertaining to the 6.2 and 6.5 motors, and how to mod them, and properly care for them.

Don

 

[Arm Auto]

Using a center mount turbo depends a lot on how much space in the engine compartment you have. I'm not at all familiar with the FZJ80. Did it come originally with an inline 6? If so, it might have enough of a stock indent in the firewall for the I-6 to be able to use the center mount turbo. But, that is pure speculation on my part.

The GM side mount turbo's are known for not being the best match for the 6.5, using today's technology. I'm guessing the center mount is the same. With the center mount you are stuck with the GM turbo. With the side mount several other turbo's have been proven to be better. Which turbo to use depends on what your end use will be, towing, hotrodding, fuel mileage, etc.

Go to this web site for GM diesels and read/search the forums for the "GM 6.5 Diesel Engines", and the "6.5 Performance". http://www.thetruckstop.us/forum/

You will find lots of info pertaining to the 6.2 and 6.5 motors, and how to mod them, and properly care for them.

Don

Thanks again Don,
You're a good man!
I've been doing a lot of reading on thetruckstop and a few other diesel specific forums. from everything I have read, the late model 6.5 is a really good option for a LC diesel swap. It was never designed to be the power house cummins 6bt or as modern as the duramax. but it gets good mileage in a LC (~18mpg to 22mpg is pretty common), parts are easy to come by, they will last if you treat them well (i owned a 3500HD) AND you can convert them to fully mechanical operation. The 4bt is way too noisy for DD and all the other "small" diesel either don't have enough power or require too much mods to make work in a LC, IMHO. Yes, they have all been done, but I see this as the "best" option for me. I really appreciate the feedback and I will continue to go "to the well" for more info as I go through my swap adventures.
I am currently doing two swaps simultaneously, a 85 fj60 to 6.5TD / NV4500 (this one got put on hold for a few months due to some family demands) and a 97 fzj 40th anniversary to a 6.5TD / 4L80e (controlled by Compushift EastShift). As we uncover "pearls" on the swap, I will be sure to share them with the mud community.
Lastly, if anyone else is interested, I ended up buying three good running 6.5 TD motors because I was able to get them much cheaper if I bought all 3 at one time. I'm planning on using the Optimizer in the 97 and was going to hold the others for a buddies swap but he decided to do his Ford f250/cummins swap first. To that end, I will have the following for sale:
2002 6.5 TD with 23,000 miles on it for $3500
2003 6.5 TD with 52,000 miles on it for $2500
Both motors are good strong running motors that are still in the rigs for the next ~2 wks) and I can send a video running to any serious buyers. The best part is these DID NOT come out of work trucks that were used and abused. They came out of the ultimate grocery getter, the civilian hummer. The motors will come with everything you need; alternator, starter, serpentine belt, intake, valve covers, oil pan, everything. They literally look like the pic above (THAT IS A PIC I PULLED OFF THE INTERNET, NOT THE ACTUAL MOTOR). If you want to do the same swap I am doing (6.5TD to mechanical injection with compushift controlled 4L80e) I can add the 4L80e for $500 more each.
If I am making a major Mud faux pas by mentioning this here, please let me know. I'll post in the Mud classifies as well as a few other "diesel" forums.

 

[dirtyboots]

Interesting...other than the rear turbo clearance are there any other fitment concerns with the 6.5? This question definitely doesn't follow your specific request, however, it doesn't seem like you can get much more info than @handcannon provided. On that note I apologize for asking off topic if that's an issue.

And on a complete derail, planning on doing anything with the glow plugs like Mercedes swap? It seems like a great engine, I had an H1 pull me out in the dunes and it sounded great and ran smooth. Is the 4L80e you're offering original to the motors you're selling?

I really like the idea. I have been reading and reading and have wondered how viable this swap would be. Looks like you took the extra step and threw down on some motors, I like. May help to provide more info on how you came across 3 motors?

 

[Arm Auto]

May or may not be some exhaust mods. I know others have had to do with side mount turbo. We will see with rear mount
This swap has been done many many times and you can find a lot on this forum as well as other diesel or swap specific forums. Although I have better luck starting my search on Google and ending up on Mud than when I start the search in Mud. Additionally, this swap seems to be very popular in Australia as well. In regards to the glow plugs, I already threw in new ones for the motor I am using but I am thinking you meant injectors? To that point, if it ain't broke, don't mess with it. But if I get bored and have some extra $$, who knows?
Lastly, the 4L80e is original to this motor. I can leave it bolted to the motor exactly as it came out, or if you don't want, I can pull it off. Please PM me if you are interested and want to talk live. Thanks!

 

[PAToyota]

Good day folks, I've got a line on very affordable low mile 6.5TD optimizer that I plan to drop in my 97 Fzj80. I really don't want to commit any space or time discussing the merits of the 6.5.

I’ve got two 6.5TDs (see signature), so I won’t argue the merits of them. As has been mentioned, if you’re looking for mileage over power they can be a decent option.

The center mount turbos were in the Hummers as well as the civilian vans. The naturally aspirated or side-mount turbo applications have bolts that are at 90 degrees to the intake manifold surface. Intake bolts that are at 60 degrees to the intakemanifold mounting face are found on the center-mount turbo manifold. Changing over to the side mount setup should not be insurmountable.

You might want to check out The Diesel Page - they’re all GM diesel aficionados, so you don’t have to wade through the “it’s junk” comments from them.

 

[handcannon]

Sounds interesting to me. I'm interested in the 6.5 in any vehicle, so please keep us informed. If I understand you correctly these motors are out of Hummers, if so they have different shaped pans than what was used in the pickups and burbs. The hummer pan has to be changed out to be able to fit the motor in GM vehicles, but I don't know about in the swap you are wanting to do. I'm interested in knowing about this for your situation also.

Looking forward to hearing how things go for you.

Don

 

[Arm Auto]

I’ve got two 6.5TDs (see signature), so I won’t argue the merits of them. As has been mentioned, if you’re looking for mileage over power they can be a decent option.

The center mount turbos were in the Hummers as well as the civilian vans. The naturally aspirated or side-mount turbo applications have bolts that are at 90 degrees to the intake manifold surface. Intake bolts that are at 60 degrees to the intakemanifold mounting face are found on the center-mount turbo manifold. Changing over to the side mount setup should not be insurmountable.

You might want to check out The Diesel Page - they’re all GM diesel aficionados, so you don’t have to wade through the “it’s junk” comments from them.

Thanks PAToyota!
I do subscribe to a couple GM diesel specific forums. And yes, there are plenty of folks out there that like the 6.5 for what it is
Also - I have PA roots too! Spent most of my youth in NW PA.

 

[Arm Auto]

Update:
We got in the garage a bit today working on the fj60 project. Today entailed marrying the NV4500 - TC Adapter - Toy TC. Almost got it done but realized we didn't have a gasket to put the TC back together. However, when I was there I took some measurements of the rear mount turbo & took some pics I will attach below. It was actually very encouraging...at least for now. The rear mount turbo only extends ~4" beyond the furthest point back on the block. And as I recall, the distributor on a 350 SBC gasser sticks back a couple inches as well and we see that swap is done all the time. Sooooo, as I see it, I am only adding an inch or two to the distance of the back of the motor. Basically I think its a little more than the SBC. I hope that makes sense. Here are some pics to clarify my point and give you a better idea of what comes with the 6.5 TD that I have.

Looking down at the back of the 6.5. Notice rear turbo at top of pic. Clutch below.

Same. Looking down but from passenger side. Notice exhaust taped off behind valve cover.

Side view of 6.5TD rear turbo (with extra fuel line because we had it running on jack stands). Notice engine stands on backwards to accommodate starter.

Front of motor with all accessories (and lift chain); alt, AC comp, power steering pump (not visible), etc. Hope that helps. Will update when I have relevant progress. Please be patient as I am doing a lot of the "minor" work on the 80 series with my 14 year old son at the same time

 

[handcannon]

Keep the pics and info coming as I'm very interested in how the center mount turbo works out for firewall clearances.

When you get a chance I would be interested in some detailed pics of how the turbo interfaces with the intake manifold, and the oiling system for the turbo. Just wondering if it may be possible to do an upgrade to a larger turbo than what GM put on there.

Don

 

[Arm Auto]

IMHO, the 6.5 TD center mount turbo is well designed system. The side mount, regardless of quality, isn't "ideal" because of the "imbalance" on the motor, exhaust, etc. Again, IMHO, I would leave this system as is and that is exactly what I plan to do with mine (both of them). They seriously run very well. I'm not looking to pull a 20,000 lb trailer up mount Whitney or drag race in Pomona
These are late model motors, not the earlier versions plagued with issues. Sure, there is always room for improvement, but at what cost & what is desired outcome & perceived/real benefit? Also, why spend money if it's not a serious issue or problem? "if it ain't broke, don't fix it". Making too many mods & upgrades starts to dig into the reason why these motors are such good options in the first place. Everything is there except the mechanical injection set-up which can be costly in of itself (4911/5088 IP, new lines, etc). Lastly, and maybe most importantly, I think (and pray to God) that this center mount turbo will require less mods than the side mount turbo. I know that with the side mount you have to do exhaust &/or shock mount mods. But I have been wrong before...once
I will get some close up pics of the setup next time I am up at the garage (about 20 mins from home).
Just my humble opinion.

 

[Tapage]

I'm pretty curious to see this engine drop onto 80 series engine bay ..

 

[45Kevin]

Make sure you relocate the PMD to a cooler (not so hot) position than under the intake manifold.

Sounds like a cool build. I love the 6.5T.

 

[Arm Auto]

Well, I got a video of the 2002 6.5TD with 23K miles running in the H1 before it is pulled, but I couldn't get the video to load to Mud. It's 60MB, 41 seconds. Is it too big? Any help is much appreciated. Thanks guys!

 

[Arm Auto]

Make sure you relocate the PMD to a cooler (not so hot) position than under the intake manifold.

Sounds like a cool build. I love the 6.5T.

Well, I could relocate the PMD, but it won't make much of a difference, I am converting the motors to mechanical injection

 

[Arm Auto]

OK, so no luck trying to upload video's. If you are seriouly interested, please PM & I can email or text then to you.
Cheers!

 

[Arm Auto]

Sorry guys, long time no update. My buddy the genius behind all this coaches football so all projects were put on hold for a while. But been back at it some so I will try to update as much as possible. As it turns out the NV4500 may not work with the 6.5 rear turbo in the fj60. The NV setup is a little short and the rear turbo extends back a little extra. Not a good combo. We did a mock fit and its either start cutting firewall or come up with a new plan. That new plan is, same motor to a 700r4. its a little longer and the measurements seem to work (I know, famous last words). I kinda like the idea of the auto anyway. We'll have to get a new TC adapter (so i will have an AA NV4500 to fj60 TC adapter available for that great Christmas gift idea ). The 700r4 came behind the 6.2 in the suburbans and we will have ours built to handle any additional torque from the 6.5T. We mocked this fit up with a 700r4 shell and the rear mount turbo fits fine now but the exhaust exits on passenger side and runs into breaklines etc. Go figure, I had a 50/50 chance and its the "bad side". So we either reroute breaklines or gain a little room by modifying the rear turbo to exit on the drivers side which is wide open as you will see from the pics below. And looks to be much better for routing exhaust.

Empty engine bay. Tons of room right?

Squeezing the 6.5 in.

plenty of room for a V8 but take note of pesky brake lines

close up of drivers side where exhaust exits

view from drivers side. removing back half of rear exhaust with waste gate. Will fab new piece to exit roomy drivers side