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What is close ratio?

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Old 07-18-2003, 09:01 PM
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Adeotec
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Default What is close ratio?

Does this have to do with the distance the shift lever travels between gears or something within the transmission?
Old 07-18-2003, 09:05 PM
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Default Re: What is close ratio? (Adeotec)

Also, what are the advantages and drawbacks of having a close ratio? Thanks
Old 07-18-2003, 09:15 PM
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tnt76vette
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Default Re: What is close ratio? (Adeotec)

Gear ratios were different from wide ratio to close ratio in 1st 3 gears. Most guys prefered close ratios for drag racing.....I dont have actual ratios to give you, but somebody else probably will....... :cheers:
Old 07-18-2003, 09:22 PM
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A C
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Default Re: What is close ratio? (tnt76vette)

M20 is a wide ratio, M21 and M22 are close ratio. The gears vary from year to year and in different cars, but a lot of the wide ratios started with a 2.52 first gear and the close ratios had a 2.20 first gear. Basically, in the close ratio, the 1st three forward gears were all higher gears than the 1st three on a wide ratio, but were spaced closer together. The wide ratio is probably a better drag racing trans, given that 1-3 gears were lower gears. The close ratio is a better road racing trans due to the tight gear spacing which would help you keep you car in it's powerband. One thing to note, at least on the early C3's, is that you could only get 3.70 rear end gears or lower with the close ratio. I assume that's because the tall first gear would cause problems with take off on a lower geared car. Do a search on Muncie 4 speeds in Google, and there are lots and lots of gear ratio charts showing all of the various manual transmissions over the years. :yesnod:
Old 07-18-2003, 09:59 PM
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Default Re: What is close ratio? (Adeotec)

In the normal car world, close ratio means that the ratios in the transmission don't change much from one gear to the next. The close and wide ratio muncies are somewhat of a misnomer though. In the wide ratio (M20), the first two gear shifts have the same % drops as in the close ratio (M21). The 3->4 drop is slightly larger in the M20 though. By modern standards, both of these transmissions are very close ratio, which is not a good mix for our large NA street engines IMO. That's the kind of transmission you'd want in race car with a very narrow power band. I don't know what those engineers were thinking.

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