Author Topic: Calculating top speeds in any given gear  (Read 4941 times)

Offline kev-yorks

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Calculating top speeds in any given gear
« on: February 25, 2007, 07:28:58 AM »
I made this a sticky as its very useful for anyone wanting to play about with wheel sizes and see what difference the make.
http://www.f-body.org/gears/
Regards Kevin

Offline 20B_boy

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Calculating top speeds in any given gear
« Reply #1 on: February 25, 2007, 10:44:04 AM »
As per the other thread from a few days back, the stock FD box ratios are:

1st 3.483
2nd 2.015
3rd 1.391
4th 1.000
5th 0.719

FWIW, my setup with 265/35/18s gives 102mph @ 4000 rpm per the calculator; this compares to 91mph in car, assuming the tach (FC Commander/dash) is accurate and the GPS is on the money. So its a reasonable indicator.
R.

Offline kev-yorks

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Calculating top speeds in any given gear
« Reply #2 on: February 25, 2007, 09:50:22 PM »
Here\'s the results for a stock FD gearbox 20b diff which is 3.9:1 and 265/40R17\'s on the rear.
I was going to go bigger wheels this year but may not bother now!:wave
REVS 1st 2nd 3rd 4th 5th
500028486997134
510028497199137
5200295072101140
5300295174102143
5400305275104145
5500315376106148
5600315478108151
5700325579110153
5800325681112156
5900335782114159
6000335883116161
6100345985118164
6200345986120167
6300356088122169
6400366189124172
6500366290126175
6600376392128177
6700376493130180
6800386595131183
6900386696133186
7000396797135188
7100396899137191
72004069100139194
73004170101141196
74004171103143199
75004272104145202
76004273106147204
77004374107149207
78004375108151210
79004476110153212
80004477111155215
Regards Kevin

Offline sadgoth

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Calculating top speeds in any given gear
« Reply #3 on: February 26, 2007, 08:15:44 AM »
ok that\'s handy, anyone have the axel and gear ratios for the FC to hand?
Mark
89 Black FC3S Turbo II
1/2 Bridge port   Microtech LT10s   TII Conv Aluminium Bonnet & Leather seats   Koni Shocks Pi Springs   De-catted 3" exhaust  
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