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4K vs. 2Y, not much difference?



We broke the lights at 92mph on that last run, we're running a 3.67 /  
16v
gear set right now.  I had to shift to fourth.  In 3rd, that speed  
would have
been about 7000rpms, past the torque peak of the motor.  For optimum
acceleration, you should be shifting just before your torque peak so  
that
the next gear up is nicely positioned on a good part of your rising
torque slope.    I suspect that we'll never be able to run a 1/4  
using only 3rd.

Since this is sooo interesting for many people, I'll break out the old
Vehicle Dynamics Calculator which basically can compute much
of what's being discussed and show it in an objective discreet way.

==Brett


On Nov 2, 2006, at 7:04 AM, C Boyko wrote:

> Brett, just for curiosity, and to pull this a bit away from topic  
> ( hey'
> it's my role)...what gearset are you using on that GRM car? Denny's  
> often
> said he'd like to stay in third at the end of the track, and he  
> can't with
> the 4K.
> Cathy
>
> On 8:28 pm 11/01/06 Brett Van Sprewenburg <brett@ataxxia.com> wrote:
>>
>> Thanks Jeff...
>>
>> Let me reiterate in the plainest words possible again:
>>
>> 3.94 R&P and .75 or .80 5th:  Very good for powerful NA 16v motor.
>>
>> One of the best mods I ever did was when I rebuilt my 2Y with a 3.94
>> and a .75 (could _maybe_ have better used the .80, but no real big
>> deal). Feels great, pulls great, and you're not building a motor that
>> makes more power then mine, so go forth and enjoy ripping through the
>> gears with a huge smile and wild abandon.  :-)
>>
>> ==Brett
>>
>>
>> On Nov 1, 2006, at 8:09 PM, Jeff Toomasson wrote:
>>
>>>  I've missed virtually every post in this thread so far so forgive
>>>  me if I'm
>>>  missing some specifics, but the FN (or like 3.89 wide-ratio box)
>>>  is IMHO the
>>>  best setup for any N/A A1 VW; unless you're going to track it and
>>>  then all bets
>>>  are off.
>>>
>>>  If your goal is a higher R&P w/ a .75 5th setup, why not start w/
>>>  the 4K? One
>>>  thing I remember from my conversations w/ Ron is that the teeth on
>>>  the 3.89
>>>  are "less robust" than those on the 3.94 (at least I think that's
>>>  how it
>>>  went...)
>>>
>>>  Also, the designation "8v 020 box" can't be used in your context -
>>>  some A3
>>>  trannies, like my DFQ, came from an 8v but have the larger "16v-
>>>  style" input
>>>  shaft.
>>>
>>>  HTH, JT
>>>
>>>>  Dan, do you think I will have any complications with the R&P
>>>>  (3.89) from
>>>>  the FN and a 9A (close ratio 8v)?  From what you described I
>>>>  believe keeping it all from an 8v 020 box should work.  Also,
>>>>  just to add more
>>>>  information, I have a .75 fifth gear set to go in it too.
>>>>  Next, I am reading between the lines a little here and I get the
>>>>  idea that
>>>>  you think the stock 16V close ratio with the 3.67 R&P is a good
>>>>  match for a
>>>>  built NA 2.0l 16V.
>>>>  Thanks, Rick.
>>>>
>