gear box selection swap or not.

[mark kibort <mkibort@xxxxxxxxxxxxxx>]

Message text written by INTERNET:bmw@domain.elided
>  Been there done it a few times. Its why most racers and hot rod junkie=
s
swap
>out there final drive gear sets(diffs in a BMW)...goes for Mustangs,
BMW's,
>Honda's, etc....
>
>Ggray
>87 535is turbo, 3.73 diff
>88 M3 Club racer, soon to have a 4.45 gear set.
<

I understand your points, but you are being way too general. If this was
the instant solution, nascars and GT1 cars would just get the lowest rati=
o
and go with that at the track.   you have to examine what speeds you will=

operate at most of the time.
haveing a great 1st and second gear that are real low,  but max speed is =
40
mph , wont do you any good if on the road course you are at a min 45mph a=
nd
top speed 110.    Now, close ratio gear boxes make sense as well as more
speeds.  =


Take Laguna for example,   top speed is 110 mph up the hill for most E30
wana be Group As.   so , if your at the very top of 4th, at the top of th=
e
hill, that transmission is good for the course,   if you went to a 3:73 ,=

you would have to shift and be at a    greater torque disadvvantage for
several seconds say 30%   (ie difference between  4th and 5th)   but for =
5
seconds earlier ,  you may have only had the 15 % difference of the lower=

rear end.  .   plus you have a .5 second or so disadvantage in the fact o=
f
you shifting.

See, Laguna may mean , wow, keep your gear box stock.   At Thunder hill o=
r
Willow where you need to get into 5th either way, the lower rear end woul=
d
make sense.  now you shift earlier, but both cars would have to shift,
giving the lower gear box the advantage.

This is the question each indy , nascar and other road guys go thru every=

single race.  Just going lower isnt the answer.  you have to see how you
will generally use the car.   if you only visit Laguna and sears point,
then run your car stock to the top of 4th gear.  if you are traveiing to
more longer tracks, swap it out  for the 4:11 or 4:45!!!!!

GEARing doesnt give you HP, just more efficient use of the engines torque=

and HP.

the science of racing.

mark

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