Looking to Build a BHW/ALH Hybrid to put in a Mk1.. how do I find the right transmission?

TDISmokeGuzzler

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1981 Caddy
Hey! New here! I used to be a part of the S2000 community, now the Corvette/LS community, but I've recently found a love for the TDI one. The information and creativity that is within it is amazing and I wanted to be a part of it.

I recently bought a MK1 caddy that I plan to TDI swap, but I'm trying to find the right route for my power goals.

I wanted to go the full ALH route, I was able to find the 3 codes of transmissions that mate with it, but after learning about the strength of the BHW bottom end, I wanted to pursue that.

Now, I'm on the BHW/ALH hybrid train, there is a running BHW near me that I would like to pick up for 1k. The plan is to inspect the short block (and refurbish) and swap the head for a built ALH one. I understand that there will need to be mods, changes, and deletes that need to happen. I've been compiling information from forums abroad! My power goal is 240 bhp.. which I feel can be done with the above parts.

Now I'm stuck on the transmission question. What transmission should I opt for?

ALH has 3 codes that mate to it, will those work for a BHW? ...will it handle 240 bhp 300+ tq?

What about an 02J? Will that present problems with the MK1?

Looking forward to your replies, thanks!
 

TDIMeister

Phd of TDIClub Enthusiast, Moderator at Large
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Why not keep it as a full BHW if you're already buying? You can make big power, like 250+, much more easily with just injectors and turbo, whereas you'll need a lot more effort to achieve the same with the ALH and VE pump.
 

burpod

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82 rabbit vnt ahu, 98 jetta vnt ahu, 05 parts car, 88 scirocco.. :/
09a CTN from an mk3 is a very nice fit...
 

JELLOWSUBMARINE

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2011 Jetta Sportwagen, 6M, red/tan, navi, pano, 83 5m diesel pickup, 82 p/u trailer,.04 5.5 TDI Passat wagon (gone), 80,81,82 diesel p/u (gone), 80,82 sportruck (gone), 59 passthru bus (long gone), 79&87 westy (gone), 57 baja bug (long gone), 73 914
I'm in the same boat. Depending on your goals, ability and knowledge there's so Many directions. Speaking for Ca., you can engine swap a mk1 (pre 1996) diesel registered vehicle to whatever, bi annual smog check free... IF... the vehicle is already initially smogged and in your name.Many swaps are bought and the new owner is held dealing with it (or not). Just a thought/consideration.

I've owned a 04 bhw, that was literally trouble free. No cam or pump issues ever, Sold it running like new at 170k (mistake). It's ALL about past ownership history.
Good luck to you.
 
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TDIMeister

Phd of TDIClub Enthusiast, Moderator at Large
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09a CTN from an mk3 is a very nice fit...
Agreed, CTNs are plentiful Stateside in every TDI A3 Jetta / B4 Passat and offer the most straightforward swap into the A1. But these are designated 02A.

Again, though, I reiterate keeping the BHW whole rather than doing a BHW/ALH Frankenstein at your power goal. Turbo, nozzles and mapping are all you'll need.
 

burpod

teh stallionz!!1
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82 rabbit vnt ahu, 98 jetta vnt ahu, 05 parts car, 88 scirocco.. :/
OOOPS! 02a yes.

sometimes "09a" slips out since the wife has an 04 with the 09a auto.. big mistake!!! :0

the CTN is nice because of the slightly taller gearing - you just want to upgrade to the 02J shift tower + linkage.
 

oilhammer

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There are just too many to list....
I vote for an 010 box, with the 087 planetary case so you can attach a heat exchanger and have the bigger internals.
 

Mozambiquer

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I'm doing a tdi swap into one of my caddys (been in the process for too long now...)
I'm going with an ahu and o2a transmission, though just picked up another passat and thought about installing a BHW instead, or a hybrid.
I got the s&p mount kit with the cable clutch conversion.
 

TDIMeister

Phd of TDIClub Enthusiast, Moderator at Large
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OOOPS! 02a yes.

sometimes "09a" slips out since the wife has an 04 with the 09a auto.. big mistake!!! :0
Well, at least the 5-speed auto installed in the PDs were an improvement over the 01M in the ALH era - however slight! :)
I vote for an 010 box, with the 087 planetary case so you can attach a heat exchanger and have the bigger internals.
Isn't that the very first-gen, 3-speed (no overdrive) autotragic? Curious to understand your rationale. :)
 

oilhammer

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There are just too many to list....
Was mostly being funny, but actually those were not a bad transmission. Fairly durable, and very simple. They used the same 3sp autobox (the planetary case) in Transporters, Audi 5000 turbos, and the Porsche 944. We had a local guy here who drag raced his A1 GTI that used one for years.
 

TDISmokeGuzzler

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Wow! Tons of useful info! Thank you!

Alright, I will stick to a whole BHW. I just figured that people run ALH because of the accessibility of parts..

The engine I'll be picking up will have 200k miles on it.. something tells me I should be replacing internal pieces before putting more power through it. Finding BHW parts seems difficult but maybe I'm just not looking in the right places.. that's why I opted for ALH. I'll definitely be going BHW full now.

I'll definitely look into buying one of those transmissions listed above!
 

Mozambiquer

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Wow! Tons of useful info! Thank you!

Alright, I will stick to a whole BHW. I just figured that people run ALH because of the accessibility of parts..

The engine I'll be picking up will have 200k miles on it.. something tells me I should be replacing internal pieces before putting more power through it. Finding BHW parts seems difficult but maybe I'm just not looking in the right places.. that's why I opted for ALH. I'll definitely be going BHW full now.

I'll definitely look into buying one of those transmissions listed above!
A balance shaft delete and tune.
May want a Franko6 cam if the cam is worn.
 

oilhammer

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There are just too many to list....
You won't be able to put a BHW in that car, at least, not in its entirety as it was in the B5.

The B5 has its engine longitidinal, the A1 has its engine transverse. So, in order to make a BHW work, you'd have to strip everything off the outside, and use transverse parts.... what you would end up with, is some sort of frankenstein engine. Possibly part BHW, part BEW. However, once you realize that it is more difficult to make an EDC16 PD engine work in your car, you'll probably go back to the much simpler EDC15 VE engine (an ALH). You can build an ALH with bigger pistons if you want.... the BHW's main difference is just that, 100cc more displacement due to larger pistons. It has a bunch of other things different than the BEW, but all of those are easily mix 'n matched.

But the turbo, the manifolds, all of the plumbing, the oil pan, the belt driven accessory bracket, etc. is all going to be unusable from the BHW.
 

TDISmokeGuzzler

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You won't be able to put a BHW in that car, at least, not in its entirety as it was in the B5.

The B5 has its engine longitidinal, the A1 has its engine transverse. So, in order to make a BHW work, you'd have to strip everything off the outside, and use transverse parts.... what you would end up with, is some sort of frankenstein engine. Possibly part BHW, part BEW. However, once you realize that it is more difficult to make an EDC16 PD engine work in your car, you'll probably go back to the much simpler EDC15 VE engine (an ALH). You can build an ALH with bigger pistons if you want.... the BHW's main difference is just that, 100cc more displacement due to larger pistons. It has a bunch of other things different than the BEW, but all of those are easily mix 'n matched.

But the turbo, the manifolds, all of the plumbing, the oil pan, the belt driven accessory bracket, etc. is all going to be unusable from the BHW.
Thanks for the info! My concern is if I were to go ALH.. what kind of cost and effort would I have to go through in order to make 240 bhp reliably..?
 

oilhammer

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There are just too many to list....
240hp diesel in a transverse FWD car like the lightweight A1 is going to be an awful car to drive, and will likely turn the transmission innards into silvery goo and rip the cheesy mounts right through the unibody. Set your goal to a more realistic one. A 150hp TDI in that little truck with proper gears will be a handful. You have to understand what torque does.

Given you have some knowledge of the opposite end of the spectrum, the Honda S2000, with its angry chainsaw engine under the hood, that provides a good example. That engine (the early ones, anyway) makes LESS torque than a completely stock 90hp ALH. And it needs to spin up past 7000 RPM to do it, the ALH manages it at a meager 1900 RPM. Horsepower may spin the tires, but torque is what breaks things. So, a 90hp TDI makes 155tq. A 240hp example (which isn't realistic for a streetable machine, in my opinion) would be cranking out something in the neighborhood of 400tq, and you are well beyond the zone of axle snapping places and such. Darkside Developments in the UK has done a lot to these engines, probably made more "peak" numbers than many. You can read up on what all they've done, but there are limits to what you can do before it just becomes fragile and absurd. I've ridden in a twin-turbo 2.0L ALH 6sp monster in a B4 Passat, and it wasn't something that was realistic to drive in my opinion. It was awesome, to be sure, but with the CR set so low, it could not even be driven until it warmed up some, and even then it was a bit slow to get going... then once it was warmed up, and the smoke subsided, and running well, mashing down on the go pedal resulted in such serious dangerous torque steer that the owner ultimately had to pursue an AWD conversion, because simply getting that much power to the ground through two front wheels was a fruitless endeavor. And this was in a B4, that is probably about 1000 pounds heavier than your pickup, and has a better engine/transmission mounting setup, can more easily accommodate larger front axles/hubs/bearings/carriers/brakes and was probably not making much more than 200hp.
 

TDIMeister

Phd of TDIClub Enthusiast, Moderator at Large
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You're going to have challenges any way you slice it to adapt the MK1's ancient fuse box system to something more modern first. Most people who attempt such a swap update the whole electric system at the same time anyway.

EDC16 is not such a mystery anymore and a number of companies sell harness kits. Alternatively, some European PD ECUs were EDC15.
 

TDISmokeGuzzler

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Thank you for taking the time to write out this wisdom as well as giving realistic examples Oilhammer. I am taking it in and will be dropping my power expectations. I drive a C6 Z06 on its edge and it feels slow for me-- just to give an example of where my head is.. it isn't screwed on all that tight. :rolleyes:

The idea of having a small truck that looks dinky to the giant American made trucks around me that can blow them away as well as have better MPG sounds like so much fun!!!

Though one thing I noticed is that you are giving torque numbers for 240 whp (400+ tq). I am only desiring 240 crank. 240 crank, that's assuming 15% powerloss.. 204 wheel.

Reading around what people make on ALH safely at 180whp/300ft-lbs, 212hp crank I think that's a realistic number to go by and probably a much easier project to stick to ALH!

And boy, I'll start my research journey with the electrical system. So far I have reached out to Fast Forward Automotive. They seem to have full conversion kits..
 

TDIMeister

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The ALH, like the BHW, is not a straight drop-in to Mk1. Engine mounting brackets will have to be swapped from an A3/B4 1Z/AHU, possibly some holes drilled and tapped on the block. Either way you go, the physical swap will be the easy part.
 

burpod

teh stallionz!!1
Joined
Nov 27, 2004
Location
cape cod, ma
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82 rabbit vnt ahu, 98 jetta vnt ahu, 05 parts car, 88 scirocco.. :/
i also suggest an ALH (or BEW) with more moderate goals. i have an AHU (stock headbolts) with an older gen vnt 1856 + 11mm pump + .260 nozzles, stage 2cam + some other little goodies, peloquin LSD + 6spd. it's an absolute dream to drive (*cough* with my own tune that is). i'd really like to put in stronger rods + ASV pistons, but don't have the time or money, and then have to deal with clearancing the intermediate shaft, which ended up being a big problem in my mk3 when that snapped :( but an ALH doesn't have that problem. upgrading the rods + pistons and doing a nice ported head isn't really that big of a deal as far as overall cost goes compared to doing another engine setup and everything else you need to do to the car.

i believe going beyond that is a waste of time and money, and you'll also start losing efficiency and drivability and cost goes up exponentially for the gains. i can tell you that with my setup, my mk1 absolutely rips, very little smoke. and i haven't even maxed out the .260 nozzles yet, it also still is perfectly smooth and drivable even puttering around at 1200rpm in 4th or 5th if you want. i haven't been able to really get a full tank of driving like a normal person, but based on my mpg's i've been getting, i don't doubt i would get 55+ without any trouble.

defintely want to re-wire the car nice while you're at it. edc15 (alh) tuning is a little easier than edc16 (bew). edc15p would be nice but you'd have to source edc15p ecu and some connectors i believe.

the motor mounts aren't a big deal, you only need a couple of them and people make them. for my ahu at least, i only needed to get the rear trans mount adapter and driver side mount.
 

adamss24

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audi a4 2.5 tdi 98 quatrro 6speed
As above, stick to the Ve engine, while the pd is easier to make power the ve is a lot smoother and revs nicer. I have 2 cars golf mk2 with 1.9 tdi VE/5 speed gearbox and the other is a 2 door mk2 fitted with a pd tuned engine. The ve is a lot, lot nicer to drive and much more forgiving !
 
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