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Discussion Starter #1
Does anyone have some close ratio gears or gearbox for 105 spider gtv berlina for sale that won't break the bank?
I'm getting tired of being beaten by MG's
Thanks
 

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Richard Jemison
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Close Ratio transmission

I have a modified GTA CR/lightened gearbox with the following ratios:
1st: 2.0
2nd: 1.52
3rd: 1.25
4th: 1.0
5th: .86

Can swap out 5th for a .92 or sell with trans as option...

$5,000.00 $5,500 with both 5th gearsets.
 

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Depends on the size of your bank! There was a Schwitters dog box for sale on an SCCA forum recently for $4000. Don't know what ratios were in it, but you could always swap out Hewland gear pairs to get what you wanted.
 

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cose ratio transmission

Richard do you have the gear teeth count for the transmission with the ratios

1st: 2.0
2nd: 1.59
3rd: 1.25
4th: 1.0
5th: .86
5th: .92
 

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Richard Jemison
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7,697 Posts
Gear count

Richard do you have the gear teeth count for the transmission with the ratios

1st: 2.0
2nd: 1.52
3rd: 1.25
4th: 1.0
5th: .86
5th: .92
Yes, I do.
32/21
21/32
26/27
23/30
21/32
22/31
 

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I'm just interested, how modified is the car? Several thousand dollars for a close ratio gearbox that may only make a few tenths of a second difference at best. A more cost effective way to chase time may be with diff ratio and especially an LSD or locked diff, or even with better/stickier tyres. If we work together we can beat those pesky poms.
 

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Foe what it is worth, when I put a close ratio box- 2.54 through .85 -into my 1300 Veloce FP car, it was worth approximately 2 seconds a lap. Sears, Laguna, etc.
 

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Foe what it is worth, when I put a close ratio box- 2.54 through .85 -into my 1300 Veloce FP car, it was worth approximately 2 seconds a lap. Sears, Laguna, etc.
That has been my experience as well. I have always had a close-ratio box, but carry a stock box as a spare. A couple years ago I had a failure and swapped tranny's between sessions. I was 2 seconds slower after the change.

The "ultra-close" boxes by Schwitters and OS Giken (sold by Spruell) have great ratios. I think you can buy the gears alone for around $3K? I'm sure they are listed on Paul's web site.
 

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It depends on the state of tune of the engine. A peakier engine with a narrow rev range will benefit a lot from close ratios but wouldnt be as benefitial if the engine has a nice wide torque band. I once had a car gain 3.5 seconds around 1.30 lap , going from an open diff to a welded up unit. The only cost was some welding wire and new diff oil.
 

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Discussion Starter #12
The car is mostly stock at this time, but plan to do more.
some suspension upgrades done, building a new engine and have to buy new tires this year.
 
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