TDI YJ Build

[Turbos10]

Great new! I just finished rebuilding a tdi in a jetta and that thing ate my lunch...doing it in a transplant...can't imagine. Cool project!

[gavan]

Originally Posted by TDIJ

I have been getting a very consistent 27 mpg +-1. I did have one tank at 20 though. It started at about 4000 feet and ended at about 10000 feet. It had a good 120 miles or so of 80MPH cruising, on a gradual uphill, and then my normal trek up the mountains from Denver.

I would expect 80MPH to hurt my mpg in my jeep... it always has. Aside from that I feel I am geared too low. I have 4.88's with 35's and it is too low for high speed cruising. This jeep will likely see plenty of cross country treks and when the time comes to install selectable lockers I will definitely be regearing to 4.56, or maybe even 4.10. I have two 4.10 open thirds that came out of my original donor 4runner, I'm curious how they will work out. I think I'll probably hate them stock... but after I tune the TDI those actually might work well. I'll see come winter when I throw the 4.10s in(for the handling in the snow with open diffs)

Your Jeep is big and heavy, and the TDI is not a huge motor. In Europe, when they spec the TDI in bigger vehicles, they gear the snot out of them and have them running 2500-3000 RPM at highway speed. You need to be close to your peak HP to keep that HEEP cruising along at speed.

When I was thinking about using a TDI in my CJ-10, I had 37s and 4.88s and I was considering going to 5.38s. I ended up with a 4BT and 37s, and I still have 4.56s, and I think they are just about right. 2000-2100 at 70 MPH.

The 6bt+ guys can get away with cruising at 1600-1800 RPM at speed, but these smaller diesel engines just can not.

I think 4.10s are going to keep you out of overdrive much of the time, and I can not see spending the money to go from 4.88s to 4.56s for just a couple revs, unless you can work out some kind of a trade.


You can not really get too mad at 20 MPG at 80 - you need a certain amount of energy to propel your Jeep against the wind at that speed. I do not think your consumption numbers are going to change much with a gear ratio change - in fact, with 4.10s, working the motor at the wrong speed, they might go down.

[TDIJ]

My gear ratio data and thoughts.

I hear you on this Gavin... but the rpms still work at those ratios. I know I should rev my TDI higher than your 4bt but I am significantly higher than you if you are running 2000-2100 at 70.

.....................60mph..............70mph..... ...........80mph

4.88 5th..........2389.................2787............ ......3186
4.88 4th..........2811.................3279............ ......3748

4.56 5th..........2233.................2605............ ......2977
4.56 4th..........2627.................3064............ ......3502

4.10 5th..........2007.................2342............ ......2676
4.10 4th..........2362.................2755............ ......3149


Practical experience driving this tells me it likes to be in the range of 2300-3000 rpms. I can run well into the threes, but it doesn't really get me any additional power. 2500 seems to be right about the perfect place to cruise.

As it is now... I use fifth almost exclusively on the highway, as well as off the highway. I run 5th up the steepest passes, as I am still in a very acceptable rpm range for power. I can drop to 4th and gain a little extra but it's not significant. Running down the highway at 65 puts me at about 2500 rpms... PERFECT!

4.10's would put me at about 2500 rpms in 4th... and about 2600 rpms at 80 in 5th. Sweet spots at both my most common highway speeds. Also the ability to run 70-75 in either gear depending on the power needed.

4.10s would give me the ability to have a better cruising rpm, while still staying in the ideal rpms, with more power on hand if needed with a quick downshift while still staying in ideal range. It leaves me with more of a 4 speed off highway, however that is fine.

4.10's might be too significant of a jump, however I am confident that i would prefer 4.56 to my 4.88. Beauty of the 4.10 possibility is I get to try it out free of charge!

[TDIJ]

Originally Posted by Turbos10

Great new! I just finished rebuilding a tdi in a jetta and that thing ate my lunch...doing it in a transplant...can't imagine. Cool project!

It's a solid little engine with plenty of potential. I'm honestly surprised at how well it pushes my brick down the road in stock form.

[steve97tj]

Are you happy with your experience so far? Was it worth the swap? Any plans for performance gains?

[TDIJ]

Originally Posted by steve97tj

Are you happy with your experience so far? Was it worth the swap? Any plans for performance gains?

Definitely happy so far. I feel like I haven't lost anything in the way of power, and gained a ton of mileage.

I will give the computer a tune, an likely some larger fuel injector nozzles at the same time. I am not in any hurry to do that though. Power is good enough for the time being, I just really want to get everything dialed in and cleaned up before I do anything else. It runs and drives, but I still have a ton of work to tie up all my loose ends.

[TDIJ]

Time for some catch up. I've been crazy busy, but I'm in something of a lull at the moment... before a surely hectic summer.

Last real build update was the front axle. All of the hub and brake modifications seem to be working as they should. The only downside I see about this configuration is that new pads might be a little of a challenge... as the rotor seems to be slightly off center in the caliper. Other than that I am completely happy with it!

That and I would have used larger rims... the calipers required excessive shaving for my 15" rims. 16" would have made an immense difference, although some shaving might still be required.

I used 1.5" diameter .25" wall and heims for my steering linkage.

gusseted the outer balls to the main axle tube.

pumpkin armor was added front and rear.

[TDIJ]

Because my engine is so high up, clearances with the hood are extremely tight. I really didn't want to cut and cowl my hood to make room, so I trimmed the hood supports to clear the timing cover and oil cap. The only other issue was the intake manifold. No trimming would solve that problem. It was also pointing towards the back of the engine, where I ideally wanted it pointing in the direction of my intercooler... towards the front of the Jeep.

I have a TIG welder now however have absolutely no experience with it. I considered modifying it myself but ultimately went on a search for someone else to make a custom manifold. When it came to costs of getting a(or several) replacement manifold after I undoubtedly destroyed the first one I figured it would be in my best interest to learn the skill on something less expensive.

I came across Matt with Whitbread Performance Innovations over on TDICLUB.COM and decided to go with him. In hindsight another person actually recommended him earlier in this thread.

I sent him pics of my engine bay, and he drew in a pic of a proposed manifold meeting my needs. We critiqued it a little and I sent him my manifold. Due to my lack of the stock turbo intake hose we were able to run a very simple and straight pipe forward, pushed out just far enough to clear the timing cover protrusion. He modified it and sent it back to me in a very reasonable period of time. He kept in close contact with me while he had it, and responded to my emails remarkably quickly.

I was happy with the price he charged as well... money well spent.

I was really interested to see the result, and all I can say is when I first saw the manifold I was impressed. The professional quality welding on this thing is beyond my wildest expectations. It fit perfectly where it should. I'm proud to have this be one of the main things people see when showing them my engine bay. Everyone that sees it instantly comments on it.

I am extremely happy I happened across Matt and will surely be using him again in the future for other things.

[TDIJ]

Wrapped the exhaust, it's cool enough to hold onto even after driving it hard.

[TDIJ]

Cooling system has been a pita! Ultimately tried routing the hoses in several ways.

1. Heater core off of the oil cooler, which provided lack of heat unless engine was revving high, so likely was not cooling the oil enough either. I think it was just too much to ask of a line that was off a T and had another path of less resistance.

2. Heater core right off the back of the head as it is in the Jetta... ignoring the restriction issues. overheating issues like crazy... then underheating issues as well as evident by temp sensor. Theory is that the thermostat is after the restriction, so it is naturally hotter, and the temp sensor is on the other outlet of the engine, so by the time the heater core closed I was reading 130 temps off of the other outlet of the engine. Clearly both lines leaving the engine were at vastly different temps.

3. As I have it now... T'd right off the back of the head, one going to the heater core and one going to the t'stat. This allowed the flow not be restricted leaving the engine, however sent coolant through the heater core right there, instead of trying to push it up from the lower part of the other side of the engine where the oil cooler is. Result is consistent heat and no fears about hot spots in the engine.

[TDIJ]

Matt with Whitbread Performance Innovations came though huge for me.

I called him up about 1pm one day, 2pm his time asking for a coolant fitting to get a sensor in my line. It was to replace a huge amount of brass picked up from the local hardware store to get me by temporarily. Hoses clamped to pipe thread like to leak in case you ever had any doubt.

I was in a hurry due to trying to prepare to move as well as several large events at the time, so I asked him to overnight it when he shipped it. He said sure and whipped this little fitting up for me out of some pipe and sent it. I had it the next day. I never would have expected him to have made it instantly and shipped it out within what could have only been an hour or so. I expected at least another day considering the time of day I asked for the custom made part. Props to him for that. Huge thanks, as that was a big help in my time crunch.

[TDIJ]

After close to 1500 miles I decided I should finally close in the tunnel.

I made this bolt on cover to enclose the open section of the tunnel, around all the shifters.

My smittybilt console fit perfectly behind this tunnel, after cutting the worthless cup holders off of it.

Huge thanks to my friend Digits who delayed his 2nd trip to Moab this April by a day to help me do this. He was also the artistic mind behind the bare metal "TDIj" left un-herculined and then clear coated.

I'm not a showy guy, and this jeep will probably not have any exterior badges or logos eluding to the engine, however this was a kind of nice subtle interior touch that I am happy with.

Digits also installed all my switches in my new dash panel/gauge cluster. That was awesome cause I wouldn't have gotten to it for a while... and I really needed a manual fan switch, and I also enjoy my heated seats again!

[TDIJ]

Couple poser flex shots... I still need to modify the front fenders significantly, as if I turn the wheel while flexing I am fully into the back of the fender, enough to limit travel quite a bit.

[TDIJ]

Took it to Chinaman Gulch for it's first wheeling trip this past Tuesday with a group of my regular wheeling buddies. It was nice to get to show them all the jeep before the move, especially as a few of them had put some hard labor of their own into it.

I told myself I was going to take it easy on it, particularly with the lack of a skid plate, but I just don't like to wheel easy! I even hung it up high centering on my transfer case crossmember once

It drove out on it's own power, and seemingly in as good of condition as it went in... successful first run in my world!

My main issue on the trail was my leaf spring hangers. They were my nemesis before I lowered them 4 or 5 inches, so now they are really in the way. Ultimately I want to french them or inboard them up inside the frame. Maybe inboard and raise, along with a spring over in the rear... keeping stock springs and near stock height but getting the springs and the obtrusive spring hangers out of the way. I'll find a solution eventually... but still have much to do to wrap up the current project as it sits now first.

[TDIJ]

I moved the day after running Chinaman Gulch and sadly the Jeep was left behind. It sits in the impound yard waiting for me to come back for it.

Plenty left to do still as part of this project:

-Front shocks... clearances are tight, top will have to be right below the hood to allow for full travel, and the steering shaft having been moved outboard of the frame will cause clearance challenges as well.

-Need to address the significant oil leak... going to do oil pan gasket and rear main seal again... but that is going to be a Massive project. I think the best way will be to pull the engine.

-New radiator with a traditional cap to help with the air issues(radiator is highest point in the system)

-Skid plate

-rework front fenders completely, probably starting from scratch, with a variation of a tube fender with flares, done in aluminum

-Rear fender armor and flares to match front, also aluminum.

-Winch install

-Many Many Many little things to do tying up loose ends and cleaning stuff up... and many more little things to redo. The list really goes on and on!

-eventual major project involving reworking of the rear suspension, custom tank, custom rear crossmember/bumper/tire carrier/hitch, and possibly outboard the rear shocks.

-Maybe I'll lift it a couple inches and throw on some 40's


Other unrelated goals:

-Cage it better, adding to stock cage most likely

-Harness seats

-Wheel it!!!!!!!

[Mieser]

If I read right your moving down to Durango? We have lived in Durango for a few years now. I just got done building this....

/forum/jeep-willys/1000503-rango-1942-willys-mb.html



If you see either rig running around town stop by and say hi. Anyone that installs a VW TDI engine in a Jeep is cool in my book! I really enjoyed your project and it sparked some possible future ideas for me. I hope I get to see it driving around town.

[TDIJ]

Durango is indeed home again... I will keep an eye out for your rigs. I'll have the jeep down here sooner or later... Need to find a place to live first!

[logs]

How did you fix the larger diesel pump nozzle problem? Back in the states again and first time filling it up at the pump and yep won't fit lol. Slight mistake in my design I guess. Finishing the exhaust today and mine will be fully road worthy...kinda.


=Jason-

[TDIJ]

Originally Posted by logs

How did you fix the larger diesel pump nozzle problem? Back in the states again and first time filling it up at the pump and yep won't fit lol. Slight mistake in my design I guess. Finishing the exhaust today and mine will be fully road worthy...kinda.


=Jason-

Welcome back!

Fixed it with a fuel cell in the back of the tub. Because of the suspension stretch in the rear I pulled the tank out. I am going to make a custom tank eventually to go in the stock location but stay flat with the frame rails. Probably only in the 10-12 gallon range if I maximize the space well!

I already gave my filler to a TJ guy, my plan when I make my tank to go under the floor is to just pick up a commercial truck filler... should be able to get one roughly the same size and shape as the YJ one.

Sweet man... It's kind of crazy to be one step ahead of you and driving it... considering you were making me drool over yours at the beginning of the winter.

Put some miles on it, I want to hear your MPG's and your opinions on how it drives.

[BCzuk]

Found this thread while searching tdi's and just wanted to say nice build. I have been throwing around the idea of a swap into my zuk forever and have always been scared of the wiring part of it. I know the manual pump is an option but nice seeing it done with success

[TDIJ]

Originally Posted by BCzuk

Found this thread while searching tdi's and just wanted to say nice build. I have been throwing around the idea of a swap into my zuk forever and have always been scared of the wiring part of it. I know the manual pump is an option but nice seeing it done with success

Thanks...

It wasn't as bad as I expected. You have to spend some serious quality time with a wiring diagram... And I made a diagram of my own as I did it, so that I had one poster board with all the wires I needed in one place. That is what helped me really "see" it. Ultimately, the wiring you need, at least for an ahu, is pretty self contained. The engine harness is all grouped together for the most part.

I considered a manual pump... For the simplicity and cleanliness of it. I figured I'd start with the electronics as it would always be really simple to manual pump it down the road if I wanted to. I definately can't say I will never change it over to a manual setup. There is just something appealing about just how clean, simple, and reliable that would be.

I am, however, really looking forward to the tunability of the computer! Ultimately no regrets thus far. Couldn't be happier with the tdi... But it's still really early.

[TDIJ]

Trip to the DMV... they said all I need to do is write a statement of fact declaring that I changed it from gas to diesel. They gave me the form and I wrote one sentence stating I changed it. It then took 20-30 minutes and 3 people to figure out how to change the fuel type. After that they said they wouldn't be able to print the new title in house because it would error based on an incorrect fuel type. They said the state will mail it to me.... we'll see?

I don't live in a part of the state that has to comply with emissions testing, so no issue there for me at this point in time.

The sate of Colorado has no safety inspections.

Ultimately, if all goes well and I receive a new title in the mail... it took 30 minutes, filling out one paper and less then $8 to make it legal.

[TDIJ]

Hit a dear in the car the day before the move... Insurance is totaling it so I went and picked up my jeep yesterday.

The jeep is officially my DD again.

Replaced the oil pan gasket... Again. Now the only substantial leak I have is the power steering hose... It is a rigged hose... Need to find someplace that can make me a real one.

[logs]

Originally Posted by TDIJ

Hit a dear in the car the day before the move... Insurance is totaling it so I went and picked up my jeep yesterday.

The jeep is officially my DD again.

Replaced the oil pan gasket... Again. Now the only substantial leak I have is the power steering hose... It is a rigged hose... Need to find someplace that can make me a real one.

I just went to a OReilly's that was local to me that made hydraulic hoses, even had the fittings I needed. Used the VW PS reservoir and works perfectly. How are your brakes btw? Mine are pretty spongy and I don't know if I need to bleed them more or go hydroboost which means new PS lines again for me.

=Jason-

[TDIJ]

Hmm... My local stores laugh at me when I ask them if they can make a hydraulic line with a banjo on one end(vw pump) and a metric fitting on the other(Toyota box)

Brakes are good. But keep in mind they are Toyota. I would think using all jeep stuff you should be fine. Only aspect you changed was the source of the vacuum right? I would bleed and make sure you don't have a vacuum leak.