Questions About Flipping 5th for 3rd, Read Some Threads But Still Confused |
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Questions About Flipping 5th for 3rd, Read Some Threads But Still Confused |
motorvated |
Jan 20 2021, 03:15 PM
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#1
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Member Group: Members Posts: 279 Joined: 13-February 13 From: Colorado Member No.: 15,519 Region Association: Rocky Mountains |
I just purchased a used Q gear set for my 901 transaxle and I am planning on flipping 5th for 3rd, using the Q for 4th, and 4th for fifth for my race car. I have read threads about how to "flip" 5th, implying that it is as simple as swapping the two gears of the 5th gear set to the opposite shafts where the old 3rd was located, driving to driven and vice versa. I haven't yet opened up and pulled the gear stack from the case, so maybe things will become clear to me when I do. Right now as I look at my new Q gear set, I see that one gear has internal splines (the driving gear I assume) and the other has a smooth bore (driven gear with syncros and dog teeth). See photos below of Q gear set.
I assume that the fifth gear set that is in the stack is of the same configuration, and if so, I do not see how the two gears can just we swapped onto the opposite shafts, as the gear with the internal splines would no longer be located on the splined driving shaft and the internal diameters of the gears are not the same. Also I am unsure of how the fifth gear syncro configuration is supposed to work with the flip. Since the syncro is on the driven gear, once flipped, won't it now be in the wrong position being on the driving gear? I apologize if my questions indicate that I really don't understand how this is supposed to work, but at this point, I really don't. Any and all help/advice will be appreciated greatly. I have already purchased Dr. Evil's rebuild DVD which I think will answer some of my questions, but I'm not sure if the DVD covers a 5th gear flip. |
Mark Henry |
Jan 20 2021, 04:53 PM
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#2
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
In Dr Evil's signature he has pages of notes you can download, I think it covers a bit about this but worth printing out never the less. It was a pretty straight forward job, but then I've also hosted two Evil tranny clinics in the past. I have a flipped HB, my gearing is A F O X and HB flipped for 5th. |
wndsrfr |
Jan 26 2021, 08:26 PM
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#3
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Senior Member Group: Members Posts: 1,429 Joined: 30-April 09 From: Rescue, Virginia Member No.: 10,318 Region Association: MidAtlantic Region |
I'm guessing you're gearing for short tracks or AX....the A/F/KA/Q/V setup sounds interesting but it's limited to like 118mph on 24 inch rear tires....23 inch will top out at 113 using a 6800rpm rev limiter....
901 gear ratio workbook makes it easy to noodle this out.... http://www.914world.com/specs/regearing_901.php |
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