ABA Swap / Gearing Questions

[SlowGoing]

Hey Samba,

So I'm finalizing my plans for the build of my Westy (build thread to come!), but right now I'm stuck on two questions: First, what exhaust to use for the engine, and second, which transmission to use.

For context, I have a 1982 Westfalia that was originally a 1.6 Diesel. It was swapped with an OBDI RV code 1.8 I4 from a 1992 jetta. The transaxle is still the stock DZ unit. I actually like this combination a lot, since the DZ allows the 1.8 to stay on tap while cruising (I can climb a 5% grades in 4th gear at 60+ mph fairly easily). BUT, the lack of low end torque can be crippling when having to accelerate up a hill, for instance. So I've decided to swap in an early ABA block to give me a bit more low end punch, while retaining the 1.8 head for fitment and simplicity sake.

Thus my questions:
I plan on building a custom exhaust from the manifold back, but which manifold should I use? Should I retain the stock ABA exhaust manifold, or is there a better option with regard to fitment and performance?

I know the block for the ABA is a tad taller than the 1.8 Jetta block. Am I in for any surprises with fitment / alignment for things like hoses and belts?

Lastly, with more low end power, I could benefit from slightly taller gearing for better cruising abilities. Ideally I'd like to be around 3500rpm @ 65mph. (For more context, I have 15" wheels with 205 tires, approx. 767 revs / mile).

Most people swap in a DK gearbox, but with the 15" wheels this strikes me as being way too tall. I'd rather go with a DM gearbox from a non-Westy diesel, but those are hard to find and it'd still be geared a bit too low. A happy medium would be a WBX 4 speed, but I've heard fitment can be an issue with a diesel engine. Is it possible to rebuild my DZ transmission with a 4.86 r&p from a DU transmission, or the 4.83 r&p from another WBX transaxle? If I were to just swap in a later WBX transaxle, what kind of work would I be looking at to make it fit with the 50º ABA block?

Thanks as always, for the help!!

David

P.S. Just to pre-emptively put on my flame retardant suit, I have searched quite a bit, and read extensively through this thread: http://www.thesamba.com/vw/forum/viewtopic.php?t=2...mp;start=0
So I do apologize if I've missed something!

PPS. If anyone is selling (or is willing to sell) a DM or DX transaxle, please please PM me!

[Zeitgeist 13]

I can't help you with the ABA part, but I did recently get to drive and work on a 1.8L RV code engine coupled to a Syncro 094 w/4.86 gearing. Since the 094 is essentially a 091/1 with a granny gear, I would guess that a stock geared 091/1 is as tall as you want to go with an NA 1.8/2.0 engine. I think the RV code is roughly the same power as a WBX (~90hp) and the ABA is something like 115hp, so there's probably not enough top end torque to justify taller gearing.
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Casey--

'89 Bluestar ALH w/12mm Waldo pump, PP764 and GT2052
'01 Weekender --> full camper
y u rune klassik?

[SlowGoing]

Was the van originally a syncro, or a WBX that was converted to have the syncro tranny? Curious to hear about how the fitment worked.

[denwood]

Check the build site in my signature. My exhaust build is detailed there. You want an Audi 80 manifold. I used the Audi 3A block as it is same height as the 1.8. You will want this engine to spin up to realize best power around 5000 rpm. My setup is an auto trans, but with modified shift points it performs well with stock gearing. My site has performance numbers as tested pre and post swap. Basically with a mildly tuned engine (although technically a 2,1 due to the new pistons) I'm at around 140 hp, and 0-60 times are down to 13.3 seconds (bare Westy), vs stock at 20.5 seconds. It performs far better than the 2.1 WBX.

You may not like the results of re gearing, as even with more power, it's still underpowered with an i4 2.0.
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Cheers,
Dennis Wood
The Grape

[Vanagon Nut]

I retrofitted a WBX transmission to the air cooled (same as diesel if I recall) engine position. In part this involved flipping the WBX transmission mount within its' bracket. This moves the transaxle further forward to accommodate OEM diesel engine position. I think Andrew Libby came up with this idea. It may be possible to keep the front shift rod and just use the rear portion. It's been suggested here that repositioning the shifter cup at end of WBX rear shift rod is a better idea then cutting out a section as I did.

some images of how I did it

https://picasaweb.google.com/musomuso/WBXTransmissionInto81VanagonWasAirCooled#

[greggearhead]

[geodude]

I did the same basic conversion you are doing including upgrading from the 1.8 block I had for several years to a 2.0L block. I finally ended up with the following combination that worked very well and that I drove across the country and all over California for many years.

1. 1.8L RD code engine from Golf GT with 2.0L bottom end.
2. Aircooled transmission with diesel bellhousing.
3. 15 inch rims with about 27 inch diameter tires.

Exhaust was not the typical system most try to use. I finally ended up with an Audi 80/90 2.0L manifold and downpipe. That made the exhaust go forward and past the transmission mount. Put the cat in the space forward of the tranny mount followed by a ball joint, then forward to a 180 bend to a muffler and then piped back to the rear. Sounds more complicated than it was and it never cracked, was pretty quiet, and good torque.
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1988 GL Camper
1991 Multivan — the basket case

[SlowGoing]

Geodude, what was your assessment of the gearing for that combination? Was the aircooled transmission too tall, or did it seem to be well paired to the 2.0 bottom end?


Thanks everyone for the replies so far!

[danfromsyr]

the air cooled transmission will pair very nicely with the 2.0 torque. unless you live at high Mtns or do any spirited towing..

I ran 205/70/15 tires on my 1.8 Digifant with an aircooled transmission and there were times it would've been best geared lower.. I tend to use my van for towing stuff.

you will have to watch the clearance with the drivers side frame member, the 1.8 intake hit it before the 2.0 block pushed it out another 3/4"

run most any muffler you like but I preferred to use the NA Diesel muffler mounts to keep the exhaust simple and hung securely. you can always make similar mounts on a vanagon 2.1 muffler or any other round muffler

you will need to modify the distributor in the 2.0 block if you plan to use the 1.8 digifant fuel injection. the block holes are different.
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[danfromsyr]

the air cooled transmission will pair very nicely with the 2.0 torque. unless you live at high Mtns or do any spirited towing..

I ran 205/70/15 tires on my 1.8 Digifant with an aircooled transmission and there were times it would've been best geared lower.. I tend to use my van for towing stuff.

you will have to watch the clearance with the drivers side frame member, the 1.8 intake hit it before the 2.0 block pushed it out another 3/4"

run most any muffler you like but I preferred to use the NA Diesel muffler mounts to keep the exhaust simple and hung securely. you can always make similar mounts on a vanagon 2.1 muffler or any other round muffler

you will need to modify the distributor in the 2.0 block if you plan to use the 1.8 digifant fuel injection. the block holes are different.
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[greggearhead]

[Vanagon Nut]

along with Dan's comments, would suggest that if you use a Vanagon muffler, try finding an Ernst. The one's I found have the extra bracing between in/outlets and body. These can't hurt. And, I ran my swap with an air cooled tranny for some time. I always thought the higher gearing + engine design itself were the cause for lack of torque down low but it turns out a faulty ECU was very likely causing this. (always felt like timing would intermittently retard). In other words, switching to a WBX tranny was not really needed beyond having a little fun adapting a tranny that *might* be a little more future proof.
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1981 Westy DIY 15º ABA

1988 West DIY 50º ABA

VE7TBN

[geodude]

I was very happy with the gearing and the 2.0. Cruised very well on the highway and I did plenty of mountain driving. I seemed to get 24 mpg no matter where I drove. But I also had the long double downpipe from the Audi which helps with low end torque.
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1988 GL Camper
1991 Multivan — the basket case

[geodude]

I was very happy with the gearing and the 2.0. Cruised very well on the highway and I did plenty of mountain driving. I seemed to get 24 mpg no matter where I drove. But I also had the long double downpipe from the Audi which helps with low end torque.
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1988 GL Camper
1991 Multivan — the basket case

[SlowGoing]

That's good to know for sure. I think I'm going to try to find a DM transmission first (already posted a wanted ad... but don't anticipate finding one given the rarity ), but if that fails I'll probably go for a DK.

There's an Audi 80 at a pick n pull near me, so I'm going to see if it still has the bottom end and exhaust manifold in there by any chance. I'd probably prefer an ABA, but might as well take a look. Fingers crossed!

[Mr. Unpopular]

I'm (hopefully) just finishing an ABA install into our 78 Westy.

Early in the build, I emailed Techtonics tuning about a decent exhaust setup. I was told by their exhaust guru (Colin I think?) that the Audi 80 manifold was the best option. I looked, and didn't see any for sale, but did see some references about them cracking "easily". I decided that wasn't a good combo for my project. I'm leaving the ABA's dual outlet manifold for now. I may build a header at a later date though.

Techtonics also told me a dual 1.75" downpipe 30" long would be best for mid range (3-6k RPM) power. I haven't built my exhaust yet so I'm not sure how easily this will be accomplished.

BTW, since I'm working on a Bay, I'm doing a 15 degree install. In this config, the ABA's stock downpipe points at the back of the drivers rear tire. In a 50 degree install, I think the stock ABA downpipe would be unusable (would point into the ground).
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"In any racing engine, the nearer you are to it disintegrating, the better it's performance will be"
-Keith Duckworth, creator of the Ford/Cosworth DFV

[SlowGoing]

Managed to pick up an exhaust manifold from an Audi 80, so the beginnings of the exhaust are in motion! The Audi at the pick n pull still had the block too, but with a 185k on the clock I figured it'd be best to pass.

Now just looking for a 3a or ABA block and the ever elusive DM or DX transmission... Don't suppose anyone has one lying around, eh?

[mellowslow]

done at 50 degrees with the later AEG 4 bolt exhaust manifold...super simple FAS bolt on. EGR blocked off.

a shot of the back during assemble...FAS kit goes together with the air cooled muffler.

I just did the fun part...spray bomb and bolt up.
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'87 WBWE FAS Gen V

[Vanagon Nut]

I was thinking about that manifold just the other day. My 4-1 "New Beetle" manifold also simplifies things.

I'm googling AEG exhaust manifold images but am only finding dual outlet types.

Is the AEG a 4-1 header type manifold?

[mellowslow]

[quote="Vanagon Nut"]I was thinking about that manifold just the other day. My 4-1 "New Beetle" manifold also simplifies things.

I'm googling AEG exhaust manifold images but am only finding dual outlet types.


Is the AEG a 4-1 header type manifold?[quote="Vanagon Nut"]

Sorry its a AEG block and BEV manifold. There is a split in the AEG production...the later AEG crosses with the BEV manifold. Very confusing but search BEV manifold. The earlier manifold is more like a header type and 6 bolt instead of 4.

http://www.ebay.com/itm/02-03-04-05-VOLKSWAGEN-VW-...35de991b90
the 4-1 makes for a much simpler piping.[url][url]
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'87 WBWE FAS Gen V