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installing OS Giken Close Ratio Gearset question

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installing OS Giken Close Ratio Gearset question

Old 04-03-06, 03:40 AM
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installing OS Giken Close Ratio Gearset question

OS Giken Close Ratio Gearset. Never installed, brand new. The information on gear ratios is on the OS Giken website and can be found here:
http://www.enonvativforce.com/close_gear.htm

The gears are straight replacements for what's in the stock transmission. 1,2,3,and 5 are different ratios. 1,2, and 3 are taller (more speed per gear), 4 is stock, and 5 is a little shorter(less speed, more acceleration). The gears go in stock transmissions and include output and half shafts. On your synchro problem, you have to replace the synchro. If you want these gears, you'd have your whole tranny pulled apart and rebuilt so obviously your synchro problem would be fixed if the reassembly is done with new parts. And yes, it works with Exedy clutches. It only changes the ratios of individual gears, so the clutch is not effected.

my car is an Infini IV and it has the 4.3 rear end which make gear feel short already.

before I got the trouble of pulling the tranny and installing this.

how can I calc the speed vs RPM before install. To see it makes the gears too short with 4.3 rear end.

I want to make sure I calc it correct. I have never had to calc the number of teeth on a gear to figure out speed, if some of you guys can shed some light on it.


Thanks





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Old 04-03-06, 04:03 AM
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If I dig some info from book in the mean time , here are the link www.lancer-evolution.com/asso/regist.html
you should get most of thing from there.

I dont think you will have top speed problem on okinawa
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Old 04-03-06, 08:23 AM
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Link does not work...

Andrew
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Old 04-03-06, 09:41 PM
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Originally Posted by diyman25
If I dig some info from book in the mean time , here are the link www.lancer-evolution.com/asso/regist.html
you should get most of thing from there.

I dont think you will have top speed problem on okinawa

yeah right about top speed.

thanks for the link.
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Old 04-03-06, 09:45 PM
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Originally Posted by andrewb70
Link does not work...

Andrew

dang their website is gone.

oh well, I was just try to post what the new gear ratios are.
FC3S
1 2.578
2 1.772
3 1.289
4 1.000
5 0.821

http://www.intecracing.com/OSGikenGearPricelist.htm
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Old 04-03-06, 09:48 PM
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what I would like to do is verifiy the ratios of the gear set I have. How do you calc the ratio of the gears? before I pull the tranny and install them I want to make sure they are the correct.
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Old 04-04-06, 10:37 AM
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why don't you pay me for the money you owe me instead of using people's money to buy stuff for yourself!



Originally Posted by 87GTR
what I would like to do is verifiy the ratios of the gear set I have. How do you calc the ratio of the gears? before I pull the tranny and install them I want to make sure they are the correct.
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Old 04-04-06, 10:28 PM
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You mean a gear calculator like this???

http://www.race-technology.com/WebPa...lculation.html
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Old 04-08-06, 07:41 AM
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To calculate the ratios, count the teeth and divide.

There are 3 reductions in the stock drivetrain:
1) input shaft to countershaft
2) countershaft to gear (1st,2nd,3rd,5th)
3) final differential reduction.

4th gear skips 1 and 2 and is therefore cannot be changed from the stock 1.0.

I assume 1) is the same since OS didn't include a new input shaft, which is necessary to change that ratio. Therefore it comes down to the ratio of the individual drive gears.
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