Possible Gear Change?

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dustin9187
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Re: Possible Gear Change?

Post by dustin9187 »

So I drove the cobra today and recorded this info:

4th gear - 40mph - 1600rpm
5th gear - 55mph - 1500rpm
5th gear - 70mph - 1900rpm

Can anyone with the stock 3.08 confirm that mine is not 3.08?
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NV93Cobra
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Re: Possible Gear Change?

Post by NV93Cobra »

Based on this website and assuming stock tires you have 3.08 gears.

http://www.bgsoflex.com/rpmmph.html
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buddha
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Re: Possible Gear Change?

Post by buddha »

From what I recall, if your just under 2k at 70mph, that would be a 3.08 rear.
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93N8
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Re: Possible Gear Change?

Post by 93N8 »

I know for a fact I have a 3:55. I never knew if the speedo was correct. But today at 55mph in 5th gear I was at 1750rpm. Then I got lucky and I was driving thru my neighborhood and there was radar parked on the road and it was telling me I was going 25mph and my speedo showed 28/29mph. So now I know the gear was never changed. So I hope this helps
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jstanley55
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Re: Possible Gear Change?

Post by jstanley55 »

Jack the rear of your car up, mark the driveshaft and a point on the tire, sping your tire 10 full revolutions and count the number of driveshaft rotations while you spin the rear tire. Then divide the number of driveshaft rotations by the number of tire rotations (10). This will give your your ratio. Then buy the appropriate speedo gear and you should be good to go.
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93N8
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Re: Possible Gear Change?

Post by 93N8 »

jstanley55 wrote:Jack the rear of your car up, mark the driveshaft and a point on the tire, sping your tire 10 full revolutions and count the number of driveshaft rotations while you spin the rear tire. Then divide the number of driveshaft rotations by the number of tire rotations (10). This will give your your ratio. Then buy the appropriate speedo gear and you should be good to go.

Cool! Thx man!
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dustin9187
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Re: Possible Gear Change?

Post by dustin9187 »

OK well then according to the rpm / speed info, my gears ARE stock. So why do i have the odometer differences?
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