Hi,

I've had a number of people ask about the Audi 6 speed Type 01E gearbox, 
with the thought of fitting it with a V8 engine in various home built 
or mid engined cars.  My answer is basically, "It's not strong enough 
to last".

There is a GT40 web site that covers a lot of this.  

People have also asked about Audi automatic transmissions fitted to
a V8 engine.  In my opinion, they are an even worse choice.

My recommendation for a gearbox to use with a V8 engine is either
a later Porsche gearbox or a special made race gearbox such as a
Hewland or similar.

The various Audi and Porsche gearbox descriptive numbers (or names)
are as follows:

    Audi 01E    -    Produced in 5 and 6 speed form.  Most are Quattro
                     All Wheel Drive.  A very few IN EUROPE were 2WD.
    Audi 016    -    Earlier 5 speed Quattro gearbox.  
    Audi 012 & 01A - Small car & engine 5 speed gearbox.
    Porsche 901    - Early 5 speed, 1964 -> 1971 in 911, until 1976 in 914 [*]
    Porsche 915    - Somewhat stronger 5 speed, 1972 -> 198? in 911 [*]
                     [*] both occasionally found in 4 speed form.  See my 
                         comments below about what breaks in these.
    Porsche 930    - 4 and 5 speed found in 930 Turbo.
    Porsche G50    - Later 5 and 6 speed gearbox.  Very strong.

The Audi gearboxes are located behind the engine in front engined cars.
Audi Quattro drives the front wheels through halfshafts from a differential
between the engine and the gearbox, and has a driveshaft flange on the rear
of the gearbox to turn a driveshaft to a differential in the rear of the car.
Quattro gearboxes have a (third) differential located in the rear of the
transmission between the transmission output shaft and the driveshaft flange
on the back of the transmission.  On various models this could either be 
locked or was a torsen differential.  If you were going to use a Quattro
gearbox in a 2WD car, the center differential (in the rear of the gearbox)
would have to be welded solid.

The Porsche gearboxes are located in front of the engine in rear engined 
cars, except that the 914 was mid engined with the gearbox behind the engine.

For starters, people have put V8 engines, Chevy LT1 and others, in 
lightened Audi cars, and the transmissions eventually fail.  In the 
Audi car, the Quattro system is used to drive all 4 wheels all the 
time, so only half the total driving torque goes through the front 
differential / wheels (the other half of the torque goes to the back 
differential / wheels).

Even with only half the total torque, the front ring gear or pinion 
bearing fails.  If you weld up the center differential and only take 
drive output through the front differential, you are then putting
ALL of the torque through the front ring & pinion, which will certainly
make it will fail MUCH faster.

Yeah, a Porsche G50 or Turbo gearbox will be expensive - but if you
do it right it's probably going to last.

As far as gear ratios in the Audi 01E gearbox, those are pretty well 
covered on my 01E web pages:
    http://www.elektro.com/~audi/01E/

The stock ring and pinion ratio is the only one commonly available.
The late Audi Allroad uses a shorter R&P, that's noted on the web page.

If you want different ratios, you will probably have to go to one of 
the German specialty shops, such as MTM.  This will cost a LOT of money.
I've seen price tags over $10,000 for special ratio'ed rally gearboxes.

Going with a Porsche 6 speed gearbox and using Porsche special ratio
gearsets will be much less expensive.  Check with a Porsche dealer
like Chuck Stoddard in Mentor Ohio.

    Charlie Smith


Here's some questions people have asked, and the answers I've given.
This is pulled out of my email archives.

Question:
---------------------
> if you could tell me the year and model Audi that had the 01E 2 wheel 
> drive trans in it.  Each time I ask the salvage yards about the trans 
> they always ask what make, model and year car the trans was in.  I'm 
> sure that they used the trans over several models and years.  The 
> gear ratios are not too important as the car will be used for cruzing 
> not racing.  Any help would be appreciated.
>  
> Thanks
> George

The 2WD 6 speed cars were the V8's and A8's in Europe, around '92 
to maybe '97.  They were never imported into the US or Canada.

I would suggest a late Porsche gearbox, it's available and also is 
stronger.  If you are planning on a healthy V8 in your car, the 
transmission may not take that much torque.


Question:
---------------------
> Charlie: I think I wrote you before! Can you advise me to which Audi 
> auto-transaxle to use with my Ford 351C eng. This is the only transaxle 
> I am aware of that might work! I was told I should use the v/8 trans 
> because it is the strongest ! If this is true what year should I be 
> looking for?  I want to use a autotrans becouse, my wife was saverly 
> injured in a bad auto accident and was told by our doctor that she 
> can no longer drive a stick-shift!

I seriously doubt that an Audi automatic transmission would take
the torque and last very long.  The RS6 uses an altogether different 
auto transmission, and Audi has detuned the RS6 V8tt to only 450 HP
to keep the drivetrain together..

The autoboxes in the 90 - 95 V8's are definitely not strong enough.   
The later V8's in the A8 and S8 are stronger, but remember that's a 
nonturbo 4.2L engine.


Question from New Zealand:
--------------------------
> Charlie
> thanks for all that information it has been most helpful. The car is in
> planning stages at the moment hence the need to research transmissions and
> my subsequent questions. I was hoping the with the light weight and
> relatively limited traction that transmission loads would not be an issue.
> It seems that I am wrong. We are planning around the 250-350 BHP mark, so
> perhaps either of the transmissions will do and we can make a choice on
> price. 
>
> The other things we have considered were the renault (eagle in usa?)
> UN1 transmission which is cheap but possibly fragile, and of course the
> porsche transmissions. The porsche G50 and later boxes are good, but the
> increase in cost means cheap dampers on the car, and I would prefer a good
> set of koni 8212's to an extra 30BHP.
>
> Is there a particular reason why the prices change so much between suppliers
> for the same audi box?
> regards Neil

Hi Neil,

The problem you will encounter is due to torque rather than horsepower.
Running a lower HP engine may actually be worse because it will develop
more low end horsepower.   As soon as you put on a beefy clutch to allow
high rpm starts to overcome lack of low end in a tweaked engine you
are right back to the torque problem.

I'll forward to you a couple of other sections of email with the other 
fellow who is considering this.  First, Scott Justusson commented on his
experience and thoughts, and then some comments I made about my experiences
with Porsche transmission failures in my 2400 lb Porsche 911 which was 
running 2.7L and 3.2L carburetted engines with very radical cams.

I remember 30 years ago a fellow was running a Chevy V8 in a Posrche 914.
The 914 uses a type 901 transmission.  He ended up using a short stroke 
crank and a radical cam to cut low RPM torque, and still had transmission 
problems.  That car was probably lighter than my 911, closer to 2100 lbs.

I'd find the money to put in a later Porsche gearbox, then you can put some
more serious power through it  :-)  No matter which gearbox, I'd definitely
run a transmission oil cooler with an external pump to circulate the oil.
That will give you more gearbox life.

I have no idea on the price differences, other than perhaps availability
and the seller not having any demand for them.


Here's Scott's comments:
>-------------------------------
> I'm presuming in fwd application not awd application?  Either will 
> work well, the 016 is good for about 400hp, the 01E probably another 
> 100hp.  The 01E has been known to have 1st gear problems (resolved 
> as of 95 with a wider first gear), the 016 weak link is 3rd gear 
> high torque blows.   Both have "issues" with small ring gear and 
> high torque, the 01E probably better than the 016 in this respect, 
> but cooling the diff oil is a big factor.
>
> For a small block ford, I'd suggest the 01E since it can take the 
> SB torque a bit better than the 016.  My buddy and I installed a 016 
> with an LT1 into a 5000 quattro chassis, and we ate a couple ring 
> gears in the trans (never experienced the "known" third gear problems).
>
> G50's are pricey, but by the time you are done here, it may prove 
> the cheapest in the long run.  You shouldn't find too much difference 
> in the O1E and 016 transmissions in terms of "adapting", in fact either 
> should share the same bolt pattern at the bellhousing, and flywheels 
> are interchangeable, the main differences are in the travel of the 
> clutch/TOB and flywheel thickness.
> HTH
>
> Scott Justusson
>-------------------------------

The next inclusion is comments I made regarding Porsche transmission 
experiences I've had in the past:

>-------------------------------
> > He wrote:
> > I'm considering a mid-engined application using the 016 5 speed 
> > behind a SBC (no more than 350HP). Several GT40 kitcars use this 
> > transaxle behind 350HP SB Fords, though there's no data yet on how 
> > long they'll last. @ 2300 lbs, they're lighter than an Audi so 
> > perhaps this may help. Some are looking at producing adapters to 
> > couple the 01E as well.
> >
> > An opinion given me by a transaxle rebuilder suggests that even the 901
> > Porsche transaxle is stronger for this application (sans 1st gear). Other
> > options are of course the 915, which takes some mod's to flip the R&P, and
> > the ratio's aren't particularly good for the V8. The G50 is pricey!
>
> Hi again Andy -
>
> I would forget the Porsche 901 transmission.  And I believe the 915 is
> questionable.  I ran a Porsche 911 for some years in speed events, and
> have a good bit of experience with 901 and 915 failures.  The engines
> were pulling enough power to take an occasional fast time of day.
>
> First, I built a 2.7L 11:1CR engine in about 1973 running through a 901
> gearbox.  The double row ball bearing on the mainshaft would go out
> about every 5000 miles like clockwork.  I got very quick at changing
> these and recognizing the symptoms.  I tore out the differential spider
> gears a couple of times, and once broke off the side carrier bearing
> neck on the differential housing.
>
> In 1978, I built a 3.2L engine, 10:1CR.  Both of these engines had 906
> cams BTW, which have NO low end torque.  This engine would cause enough
> distortion inside the 901 that I couldn't get it out of 1st gear sometimes!
> I never figured out what was distorting, and that transmission is still
> laying in the corner of the garage I think.
>
> I put a regeared & reworked 915 Mag case box in the car, and only had a few
> failures.  One failure ruined the mainshaft, as the fixed second gear was
> shoved against the end of the mainshaft splines hard enough to break off
> the tips of the splines that locate the gear.
>
> In a 915 gearbox, there's no question that you need to use a ZF limited
> slip differential.  It gets around the spider gear and diff housing
> weakness problems.  The 915 uses essentially the same differential as
> the mag case 901s.  Differentials are different for the 7:31 and 8:31
> R&P.  The flange that locates the ring gear is in a different place.
> You can machine a 8:31 ring gear to use it on a 7:31 carrier.
>
> This 911 weighed right at 2400 lbs, so you can figure how that relates
> to your intended project.  On the plus side, both the 901 and 915 can
> have the ring gear flipped to the other side of the differential case
> to cover the transmission being behind the engine.  Look at 914 shift
> conversions for the 915, it was done back when.
>
> I'd strongly recommend looking at a later Porsche turbo or 6 speed
> gearbox.  Don't run the pinion gear backwards, the tooth loading will
> be all wrong for any life.  I'd run the engine backwards if need be;
> look at marine kits to let you do this.
>-------------------------------