4K vs. 2Y, not much difference?

[jdbubb at verizon.net (Dan Bubb)]

The difference in length of the pinion shafts is only due to the fact that VW at some point used a needle bearing on the end of the pinion shaft.
The needle bearing is no longer available although any other part in the tranny is (to my knowledge).
Some pinion shafts weren't designed for the bearing, some 5th gear housings didn't have the bearing or even a protrusion to house it.
Apparently it's superfluous.
All other linear spacing along the pinion shaft of bearing surfaces and splines is identical.
If it matters you can get a 3.67 FD that will assemble with the "8V" gear sets, but you cannot get a 3.94FD that will assemble with "16V" gear sets. ("16V" being defined as the large input shaft trannies)
As far as Klaus, I'd suggest you hold off on modifying the tranny until you've realized your power dreams. ;^)
I know two guys that have the power level you aspire to and have the tallest gearing you can build in an 020 box that never feel the need for tighter gearing.
Dan 

 From: "C Boyko" <roccit_53@scirocco.cs.uoguelph.ca>
Sent: Tuesday, October 31, 2006 10:12 PM
Subject: RE: 4K vs. 2Y, not much difference?
 
> On 8:41 pm 10/31/06 "Rick Kellner" <rfkellner@snet.net> wrote:
>> Cathy, if you swapped out the R&P on the AGB (same gear ratios as the
>> 2Y) you must have swapped out the fourth gear drive too, correct?
>>
>> I have a FN with the 3.89 R&P and a 9A (again, same close ratio gears
>> as 4k, 2Y, AGB) that I might try to make a 4K-like as you describe.  I
>> figure any 4K (or any 020 box) I pick up is going to need to be torn
>> down since the ones I seem to find have 150k miles on them.  They are
>> probably nearing SMS time...
>> Rick.
>
> Yep, I had my neighbour do the build, he's a professional tranny guy. But
> fourth got swapped, the AGB fourth just does not fit the 3.94 pinion 
> (which
> I got from Peter, new). And fifth got swapped because it will drive you
> insane otherwise, I'd like to do Klaus' too. (and may as well do the diff
> too while you're there, hell, it's only money). I have pictures of the two
> pinions, they don't look at all alike, the AGB one's longer (and I think
> skinnier, IIRC, the .org gear chart would confirm that). It's a
> frankentranny, just like all my stuff ends up, it seems. Appropriate for
> Oct 31, no? :)
> Cathy