Mitsubishi 4D34-2AT3B diesel swap into 96 FZJ80

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I thought you were using the Fuso mounts. The vibrations are really not that bad. It is a bit annoying but with the idle turned up a bit, it's quite liveable. It reminds me of my 3B powered BJ60.

The exhaust will work fine on the inside of the frame, mine fits well, 3 inches to past the transfer case. The rear section is still stock, but there is lots of room back there for my 3 inch rear section. Huge bonus of now having the exhaust protected and I have not really noticed an increase in heat through the floorboards.
 
I thought you were using the Fuso mounts. The vibrations are really not that bad. It is a bit annoying but with the idle turned up a bit, it's quite liveable. It reminds me of my 3B powered BJ60.

The exhaust will work fine on the inside of the frame, mine fits well, 3 inches to past the transfer case. The rear section is still stock, but there is lots of room back there for my 3 inch rear section. Huge bonus of now having the exhaust protected and I have not really noticed an increase in heat through the floorboards.

Well I've never owned a diesel powered anything, so the worst thing I'll be able to compare it to is a cam'd v8 with solid motor mounts, haha!

The only spot where I'm unsure if the 3" will fit is where it goes over the frame in the rear above the axle. The factory exhaust was crushed there for clearance. I haven't checked if 3" pipe will fit or not yet. We'll find out Friday! Stopped at the welding supply place today for the correct wire and gas for the stainless...
 
Hey, when you are into your wiring, can you note what number fuel rate resistor you have? I want to compare to see if they are both set up the same. I am thinking of putting a 15K pot. in the loop to mess with the rate. I figure I can hit the pre-set points pretty easily and at least see what happens. Imagine if this worked, a "fuel rate" knob on the dash!!! I wonder if the computer would be able to deal with the fuel rate value moving on the fly.
 
Hey, when you are into your wiring, can you note what number fuel rate resistor you have? I want to compare to see if they are both set up the same. I am thinking of putting a 15K pot. in the loop to mess with the rate. I figure I can hit the pre-set points pretty easily and at least see what happens. Imagine if this worked, a "fuel rate" knob on the dash!!! I wonder if the computer would be able to deal with the fuel rate value moving on the fly.

Ironically, I was going to ask you the same thing!

My resistor is a #3...
 
Mine is a #2!! I just hope more ohms means more fuel.

One of the interesting things I noted on mine was a tin seal around the resistor, similar to an anti-tamper seal on an injection pump. I am fairly certain that this will do what we hope it will.

I am putting the exhaust in tonight. Will advise on running over at rear axle, I think it will fit, but a few HDJ81 people have run it with a different routing so maybe it does not. Regardless it will be 3 inch to the end.

My advice is learn to tig. If you have the gear practice a bit, you will pick it up quick, especially stainless, it's by far the easiest to learn on. It's all about finding a rhythm and sticking to it, you will be amazed how it goes after it "clicks" and you start to get good at it.
 
Hey, when you are into your wiring, can you note what number fuel rate resistor you have? I want to compare to see if they are both set up the same. I am thinking of putting a 15K pot. in the loop to mess with the rate. I figure I can hit the pre-set points pretty easily and at least see what happens. Imagine if this worked, a "fuel rate" knob on the dash!!! I wonder if the computer would be able to deal with the fuel rate value moving on the fly.

On the fly adjustments are pointless. When would you ever turn it down?
Better to tune it for a safe maximum and then use the right pedal for control as you usually do.

Unlike a petrol there is no loss in economy when tuning for more power. The only loss in economy is from driving faster.
 
Mine is a #2!! I just hope more ohms means more fuel.

One of the interesting things I noted on mine was a tin seal around the resistor, similar to an anti-tamper seal on an injection pump. I am fairly certain that this will do what we hope it will.

I am putting the exhaust in tonight. Will advise on running over at rear axle, I think it will fit, but a few HDJ81 people have run it with a different routing so maybe it does not. Regardless it will be 3 inch to the end.

My advice is learn to tig. If you have the gear practice a bit, you will pick it up quick, especially stainless, it's by far the easiest to learn on. It's all about finding a rhythm and sticking to it, you will be amazed how it goes after it "clicks" and you start to get good at it.


Interesting that your truck has a different resistor. I wonder if it is a sort of calibration for the injector pump? I'm curious to see your results in changing the resistor!

I finished the exhaust... MIG'd the whole thing... TIG will have to wait for next time. I pre-heated the exhaust housing with a torch to promote good penetration, I think it came out quite ok.

I also did a little trick on the v-bands. I made one of every connection a "Male" by allowing the pipe to protrude past the flange'd part by a 1/4 inch. This allows easier alignment of the next piece when assembling as they hold each other together. Worked out well....

Anywho, on to the pics!!!
IMG_8335.webp
IMG_8336.webp
IMG_8338.webp
 
On the fly adjustments are pointless. When would you ever turn it down?
Better to tune it for a safe maximum and then use the right pedal for control as you usually do.

Unlike a petrol there is no loss in economy when tuning for more power. The only loss in economy is from driving faster.

:meh:

I'm tired... long day's work behind me. Tomorrow I finish the AC and fuel system, and if I have time I'll start the wiring.
 
Pointless? Hardly. I lend my truck out to a lot of people and I do not want to have to educate them on the pyro. It would be sweet to set it to max fuel when I am driving and then cool it down for someone else. Plus, just for tuning, it would be awesome. Just go full throttle up a long grade, and keep increasing the fuel until it's right on the money at max EGTs you are comfortable with.

Good work on the exhaust! I usually butt weld them with the tig but that looks a heck of a lot simpler and stronger with the expanded joints.

I am copying your rear muffler hanger! Good idea. Also glad you got the 3 inch above the frame. How much free play is there? With your hanger setup it should be rigid enough not to move. Mine has a rattle on the floor that I will need to address tomorrow morning.

I don't want to mess with the fuel until I have a pyro in there... Might steal the one from the Land-Rover...
 
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Pointless? Hardly. I lend my truck out to a lot of people and I do not want to have to educate them on the pyro. It would be sweet to set it to max fuel when I am driving and then cool it down for someone else.

A valet switch (usually hidden) is no problem. But otherwise more boost is the answer. I get sick of watching the pyro too.
 
Good work on the exhaust! I usually butt weld them with the tig but that looks a heck of a lot simpler and stronger with the expanded joints.

Yea, I woukd have butt welded them, but I wamted to keep it simple. A couple joints are butt welded out of necessity though.

I am copying your rear muffler hanger! Good idea. Also glad you got the 3 inch above the frame. How much free play is there? With your hanger setup it should be rigid enough not to move. Mine has a rattle on the floor that I will need to address tomorrow morning.

There is about 3/8" above and below the pipe. I also clearanced the pipe in some areas with strategic hits from a hammer, again out of necessity. I'm anxious to hear how your truck is with the full 3" exhaust!
 
Super build and detail, thank you.
I'm sorry you rushed through the trans stuff tho, I lost you at the parking paul.... and your end result. How did it all come together?
Also, any clearance issues with this trans in the later FZJ body?
Did you mod the trans cross member in any way?
Cheers,
 
Super build and detail, thank you.
I'm sorry you rushed through the trans stuff tho, I lost you at the parking paul.... and your end result. How did it all come together?
Also, any clearance issues with this trans in the later FZJ body?
Did you mod the trans cross member in any way?
Cheers,

Thank you...

The park lock pawl went like this...

The park rod, which connects to the shift actuator in the front of the trans, runs through the case next to the valvebody, and out the back of the case is the same length between both transmissions. The end of the rod that ends up in the extension housing is larger in diameter on the AW450-43LE than on the A442F. There is a small guide that bolts inside of the extension housing that the park rod slides in. The groove in this guide is also larger on the AW450-43LE than on the A442F. As a result, the bolt spacing is slightly wider on the AW450-43LE guide. Wider by enough of a margin that the AW450-43LE guide will not bolt into the A442F extension housing.

This was a problem, since I already reassembled my transmission with the AW450-43LE rod in it. Changing it meant taking a whole lot of stuff apart that I had no desire to do. Instead, I modified the guide by enlarging the holes so it would bolt into the A442F extension housing. However, this guide (Like the rod end) is HARDENED steel. No drill bit I had would even make a scratch in it. I ended up using my plasma cutter!!! My advice, use the park rod from the A442F when you build your trans.



The second problem with the park rod is that it is not long enough to engage the pawl when the spacer is installed between the extension housing and the transmission. I took some pictures out of Fromage's and Astr's threads to try to illustate the problem and my solution.

The first picture is a look into the A442F extension housing, you can see that the guide is bolted in on the bottom right with two bolts. It is hard to see, but behind the park pawl arm, you can see two arm sticking up. The skinny end of the park arm slides between these two arms. This is what is wider on the AW450-43LE than on the A442F. I tried bending them apart to make the room and they just snapped since they're hardened steel.

In the second picture you can see the park rod protruding from the back of the transmission.

In the last picture I added some letters/colors/arrows and I'll try to explain what I did. The top of the third picture has colored letters over parts of the park rod. The shaft labeled green "A" is what slides between the forks on the guide, it is a hardened steel tube, slid over the park rod, and welded at the end.

The part labeled pink "B" is what actually ENGAGES the park arm. When you put the trans in park, the entire arm slides to the rear, and this fat portion pushed the park arm up into the park gear to lock the trans into park. This park freely slides over the park shaft, the spring labeled blue "C" keeps it pushed against shaft "A", but it can be pushed forward compressing spring "C" when the trans is put into park. This is to soften the impact when "B" hits the park arm if the park arm is not in alignment with the park gear.

When my extension housing was installed and I put the trans in park, the entire park rod assembly would not move back far enough for "B" to engage the park arm seen in the top picture.

Astr removed sleeve "A", component "B", and spring "C", put a spacer under spring "C", reinstalled "C", "B", and "A", and welded "A" in place further down the shaft, essentially lengthening the whole assembly by the distance of the spacer.

Since I did not want to tear my whole trans apart, I took a different approach. I stuffed/covered the whole rear of the trans with rags and used a small cutoff tool to cut "A" down by 3/8" on the end closest to "B", as seen in the bottom of the third picture. I DID NOT CUT THROUGH THE ENTIRE ROD!!!! I worked my way around and ONLY cut through the Sleeve, then split it off of the rod!!! DO NOT CUT THE WHOLE PARK ROD!!! I was banking on the fact that spring "C" would extend far enough to push "B" further down the park rod and into sleeve "A" in a new position. It worked!!! Since "B" was in a new position further down the shaft, it would now engage the park arm, putting the transmission into park.




I know this entire description was very wordy, but it was the best I could do. Clear as mud?
IMG_7753.webp
IMG_8061.webp
park rod 1.webp
 
Also, any clearance issues with this trans in the later FZJ body?
Did you mod the trans cross member in any way?
Cheers,

Sorry, forgot to answer your last two questions.

No clearance issues at all.

Trans crossmember is unmodified and bolted right in. It should... they're the same part number regardless of trans that came in the truck.
 
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