Tranny question

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cmiller
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Tranny question

Post by cmiller »

Trying to identify the gears in 5626 rod change box. These particular gears have two grooves rather than one as normal on an A+ box.
Any one have an idea on the the significance of the two grooves. I am stumped.

Chris Miller
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timmy201
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Re: Tranny question

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Spider
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Re: Tranny question

Post by Spider »

You had me excited when I read your thread title,,,,,,

The Twin Line Gear sets have the widest ratios of any factory gear set.

1st 4.00: 1 :shock:
2nd 2.30:1
3rd 1.43:1
4th of course is 1:1

They used these in some of the later 998 engined Minis some SPI's and I think all MPI's. They went to these to off set the tall final drives these cars had.
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Peter Laidler
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Re: Tranny question

Post by Peter Laidler »

Me too Spider. Oxford being a social hub for them - but not necessarily mini gearboxes........
CooperTune
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Re: Tranny question

Post by CooperTune »

I have been using this gear set in some of my highway cruiser minis. Building a large over bore high torque at low RPM 1275 and two over drive drop gears also factory parts. Result is finial drive ratio around 2.56 with MPH of 70 at 3000 RPM. My first build was for my 1360 Cooper S for the ride out to Mid Ohio for the Can Am mini race. At first with 145/10 tires I could not control wheel spin in first, tried 145/12s with the same problem. 165/12s work best. The nearly 1000 RPM drop between gears could be a problem with the wrong cam. I recorded 96 MPH on my GPS in my car and have seen slightly over 100 in a customer's car. Clearly not for everyone but here we can drive 3000 miles in one direction and still be here. Steve (CTR)
cmiller
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Re: Tranny question

Post by cmiller »

Thanks for the answers guys. Got it figured out now. Have to be more careful on choice of words in title. Glad I offered a little amusement.

Chris Miller
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