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VW TDI Swap info/guide

277K views 138 replies 29 participants last post by  Motohead1 
#1 · (Edited by Moderator)
Ok, so there seems to be a ton of misinformation out there regarding the TDI motors and swapping them. I'm here to set this straight! I own a TDI specialty shop and have been working/modifying/swapping them for 7 years now. I've been there and done that with just about every avenue regarding them and will try to share my knowledge. I'm not going to discuss the IDIs are I feel they're barely adequate for a lawnmower on a good day with a hurricane tailwind.


List of basic motors that are out there that are good for swapping.
  • AHU/1Z - These are found in 96-98 Jettas and Passats. These are the old-style blocks with an intermediate shaft and external water pump that are basically the same from the mid-'70s till 98. Easy to recognize by stamped steel valve cover with 3 bolts in the center holding it down. They come with a wastegate turbo that's the size of a pop can. The wiring harness is very simple and the ECU doesn't have an immobilizer. However, to tune the ECU it needs to be socketed and burned chips installed. Not a huge deal for any tuner, just an added annoyance IMO. They can be converted for VNT turbo operation by a vent-specific ECU tune and a 00-03 N75 turbo solenoid valve. Extremely worthwhile if you insist on using this motor. The main drawbacks to these motors are: slightly poorer flowing heads than later motors, the tendency for oil leaks, 80kmi timing belt intervals, accessory bracketing sucks, and the ECU is rather dumb (think dos vs windows 98). If you're not planning on much over 150hp and you get one for cheap, they'll serve you well enough. If you want lots of power, skip to the next options.
  • ALH - Found in 00-03 Jettas, golfs, and beetles. Technically ALH's were available in beetles from 98-03, but the 98-99 beetle ECU/harnesses are bastard child and totally unique. Trust me when I say stay away unless you get them for free, in that case, sell them for a 00-03 ECU/harnesses. You'll thank me later.

This is my personal favorite, basically the 4bt of the VW world. Simple and best bang for the buck to modify. Can be brought up to a reliable 200hp/350tq with bolt-ons, 275hp/450tq if you want to delve inside. ALH was the first diesel of the new engine block design that did away with the intermediate shaft and external water pump. Uses many fewer gaskets so generally much lower tendency to leak oil. Easy to recognize by cast aluminum valve cover held with 5mm Allen perimeter bolts. If you can, get the motor (or at least the injection pump) off of an automatic car. Auto cars had 11mm plunger pumps, manuals had 10mm plungers. These motors have VNT turbos that are mounted on a turbo-fold. Kind of a pain for starter clearance on passenger side starter swaps. The easy solution is to get a 04-05 Passat TDI manifold & turbo (small upgrade from stock ALH turbo) or any of the aftermarket 8 valve 4 cylinder exhaust manifolds on e bay and put on a bigger turbo (you know you want more power). Either of those manifold options will pick the turbo up and away from the motor giving you more clearance for starters.

The wiring on these may look somewhat intimidating at first to those that aren't electrical friendly, but once you get it, it's extremely simple. The ECU for these is also much smarter than the older ones and is OBD flashable with a loader. Once the immobilizer is deleted by a tuner, there is no need to use OEM key, cluster, or any of that crap. I can't even say how many people I've seen go through the hassle of trying to hide an OEM key and cluster because so and so told them there was no way around it. Total BS there.

  • BEW - These are found in 04-05.5 Golfs, Jettas, and beetles. These are unit injections, with no external injection pump. Same short block as an ALH, just a different head. ECU/harness on these is very similar to the ALH once stripped for swap use and immobilizer deleted. The only major issue with these (and any of the unit injection motors) is that the cams are ground wrong from the factory with incorrect geometry. Somewhere between 50K and 150K, the cam and lifters will need replacing. The good news is a few years back I worked directly with Colt Cams to develop fixed profile cams that don't eat themselves. The bad news is because the cam is billet steel, it isn't a cheap job. A cam kit with cam/lifters/bearings/gaskets is $920. However, these motors are very quiet and smooth compared to the AHU/ALH. Power potential with these is just as good as the ALH, just more expensive to upgrade injectors on these vs the earlier rotary injected motors.
  • BHW - Found in 04-05 Passats. These are the most powerful factory TDI motor offered in the US at 135hp/236tq. With just a tune these jump to 170/325. Also the only factory longitudinal motor so accessories and oil pan are much more suited for longitudinal swaps. They also have a more traditional turbo/manifold setup that puts the turbo up much higher than any of the first 3 motors talked about. The turbo is also 3mm larger, and will make about 20hp more than stock ALH/BEW turbo. These are basically the same as a BEW with slightly larger injectors, 81mm vs 79.5mm bore (these are a 2.0L instead of a 1.9L), 2mm larger rod journals, and 1 point lower CR. With the bigger rods, these will hold 240whp on stock internals without ever taking the head off (~275hp with a ported head), just a $200 set of arp studs for cheap insurance. The downside with these is they have the same cam issues as BEWs. One other unique item these have that must be addressed is a chain-driven balance shaft module that bolts to the bottom of the block. It's a piece of epic fail that you need to toss in the scrap bin. The normal oil pump and chain drive from an ALH/BEW bolts right on and fixes that clusterfook. I'll post PN's for that later on.
  • BRM - Found in 05.5-06 Jetta and beetle. VW's next block architecture design with a $120 rear main seal. It's basically a slightly updated BEW with a high mount turbo and more EGR bs. I would suggest avoiding it unless you get it dirt cheap as it is a unique wiring harness/sensors. The ALH/BHW/BEW share many of the common maintenance items that are much cheaper. These also are unit injections and have the same cam issues.
  • CBEA - Found in 09-12 jetta and golfs. These are the latest and greatest common rail, DOHC motors chocked full of emissions garbage courtesy of uncle sam. Great platform for power once "fixed", but still too expensive/complex for mainstream swaps just yet. I'd suggest sticking with one of the older motors for a few more years. I'm putting one right now into a race car at work, but the budget is of no concern when the customer is some hedge fund manager. Must be nice :eek:

Many more updates will be added over the next few days. sleepy time now. Stay tuned.
 
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#4 ·
thanks for that info. i am new to the turbo diesel world, and this forum. i have a 98 tdi that runs great but the car is very rusty. is there a tranny that would bolt up to this engine to convert to rear wheel drive? i am into rat rods and would love to use this engine for a cheap daily driver.
 
#6 ·
Easiest route for rear wheel drive is an acme adapter kit for a toyota 2wd or 4wd trans setup.

Thanks for this! I have a 99.5 jetta which I am about to part out. I am planning to use the alh in a volvo 122 swap one day. I have heard that the ecu for these is wierd, too as it was an early model. Anything I should be aware of?
Yeah, 98-99 beetle and 99.5 jetta/golf are goofy ecu's. As you already have it, just send it to a tuner (TDTuning is my preferred choice) for socket job, immo delete, and set of tuned up chips. The 00+ ECU's are flashable and don't require burning chips to change the tune.
 
#5 ·
Thanks for this! I have a 99.5 jetta which I am about to part out. I am planning to use the alh in a volvo 122 swap one day. I have heard that the ecu for these is wierd, too as it was an early model. Anything I should be aware of?
 
#12 · (Edited by Moderator)
Damn, I knew the K car motors had VW bell patterns, but I had no idea the early Dakota 2.5's were the same. I'm a chevy guy so I never really dug into it much as I had no desire to tdi swap a K car haha. That's awesome to know! Here's a neat page I found on a quick search showing the early 2.5L Dakota bell and what transmissions it will bolt to.
Vehicle brake Automotive tire Locking hubs Rim Gas
 
#13 ·
Clarification; I am confused. If the ALH motors stopped in 2003, why do I always see the parts listing extended to 2006? Like for my timing tool set, its for "99.5 - 06 Golf TDI ALH and 99.5 - 06 Jetta TDI ALH"?

Or is it that, between 2004 and 2006, you could have EITHER engine in those cars; you'd need to look for an IP or not to know for sure?
 
#14 ·
I hope you will provide accurate and reliable information about m-TDI injection pumps.I have read everything I can find on the and it's confusing as hell.Also power numbers are 130hp to 280hp with just an m-TDI pump tuned properly.I'm planning to attempt to build two m-TDI pumps for my 1.9TDI I'll be putting in my boat when I get it built.I'd rather stay away from a dyno but I may have to go away and find one.I don't think there's an engine dyno within 500 miles of me.
 
#21 ·
All watercooled 4 cyl VW/Audi motors share the same bolt pattern, gas or diesel. So yes, you can directly swap a 4 cyl gasser to a 4 cyl diesel. If you're swapping a longitudinal engined Audi or making a mid engine vehicle with an Audi transaxle, they will bolt to any 4, 5, 6, or 8 cyl VW/Audi engine. The transverse VW/Audi transmissions are 4 or 6 cyl specific.
 
#137 ·
Sorry to post in reply to an old post. I tried to private message you, but couldn’t find a link to do that. I’m going tomorrow to pick up an ‘04 BEW engine and ECM to swap into my ‘96 Geo Tracker. I saw in another post that you do harnesses. Would you be interested in trimming down the BEW harness to be standalone for me?
 
#24 ·
Whitbread, you said that you were putting a CBEA engine in a race car. I would like to know what you did for the ECM. I have a customer here that has put a CBEA in a Superlite Car but is having problems with the ECM letting the car go over 50 MPH do to the ECM not seeing the information over the gateway for the ABS module, VSS signal, etc. He has had a Malone Tune put into it to try and work around that, but with no success. Can you give me any hint on how I can get this thing to run right other then putting in a gateway module and ABS module?

Thank you,
Todd
 
#25 ·
If this thread is still monitored, I have a 98 Jetta donor and am wanting to put the TDI in a 62 Jeep truck. Preferred would be to keep the original T90 trans with the Spencer overdrive. (It's a lot of fun to have it valet parked with 4 shifters on the floor and two of them will disengage the drive!) I'm not having much luck locating the bits to mate those two together, so getting something like a toyota 5 speed is not out of the question. The best part is there is LOTS of room in the engine compartment to play around with!
 
#27 ·
HI, I have a BRM TDI that i put in my rat rod and im trying to get it to fire up i have the vehicle the engine came out have and i pulled the harness out and had the immobilizer delete, I got a wiring diagram and followed it to a T and i still must be missing something. Wondering on any tips on what the computer needs to see to start up.
 
#28 ·
HI, I have a BRM TDI that i put in my rat rod and im trying to get it to fire up i have the vehicle the engine came out have and i pulled the harness out and had the immobilizer delete, I got a wiring diagram and followed it to a T and i still must be missing something. Wondering on any tips on what the computer needs to see to start up.
Check out the forum here. https://www.tdiclub.com/
 
#31 · (Edited by Moderator)
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#33 ·
I used the TDI compressor so new lines with the mating TDI ends were built.
Its usually easiest to use the TDI accessories since they are already on the engine with all the correct brackets and belt.
I looked at using the Ford compressor but more work that changing the lines.
 
#36 ·
Mating to a Velvet drive souldn't be a problem. You just need to figure out how to mount a drive puck to the flywheel and make an adapter plate to mount the drive to the engine. I would use a heavy flywheel to prevent the engine from stalling when idling in gear.

A couple guys on boatdesign.net and on tdiclub.com have marinized 1.9 and 2.0 TDIs for some fairly substantial boats, replacing the old V6s and V8s. The 1.6 and 1.6T were marinized by Pathfinder marine until they closed up in the 90's, IIRC. There is a company that is currently using VW and Mercedes diesel engines in their diesel engine packages. I can't remeber which company it is tho. I'm out of touch. I had considered marinizing a 1.9TDI for a boat I want to build and out it in front of an Alpha I Mercruiser sterndrive.
 
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