Bullet Proof Transmission
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Joined: Jun 2006
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Bullet Proof Transmission
Well I have had it with My05 and the crunching transmission with only 6700 miles on it!
Part of the problem is the synchros are not made to take the 8000 rpm shift from 1>2 without a pause and thats BS!
I drove a Boxster S and beat the hell out of it without ever having a problem.
I think part of the problems is the main input shaft weights in at about 20 lbs and so when you think about the shift from 1>2, the inertia of the input shaft including the clutch disc and gears needs to be slowed down from 8000 rpm to 50000 rpm, or about 3000 rpm to make the shift without a crunch. The synchros are responsible for slowing the input shaft down to synch with the output shaft.
I love this car, but the transmission is horrible.
I've read a lot about the tolerancing and other items on the S2ki site, but what I am intrested in is your thoughts on how to make the Synchros last for ever and improve the overall tolerances in this transmission.
SPOON does some work on these things. Does anybody know what they do!
I have also read a lot about cyro gears and stuff like that so any help on this subject would be appreciated as well.
I am going to take the trans out of the car in a little while and I want to build the trans to be bullet proof so that I can do the 8000 rpm 1>2 and 2>3 shift without beating the Synchros and feeling a crunch!
Any help is appreciated!
I had a Boxster S and used to redline it all the time and it shifted like butter!
Part of the problem is the synchros are not made to take the 8000 rpm shift from 1>2 without a pause and thats BS!
I drove a Boxster S and beat the hell out of it without ever having a problem.
I think part of the problems is the main input shaft weights in at about 20 lbs and so when you think about the shift from 1>2, the inertia of the input shaft including the clutch disc and gears needs to be slowed down from 8000 rpm to 50000 rpm, or about 3000 rpm to make the shift without a crunch. The synchros are responsible for slowing the input shaft down to synch with the output shaft.
I love this car, but the transmission is horrible.
I've read a lot about the tolerancing and other items on the S2ki site, but what I am intrested in is your thoughts on how to make the Synchros last for ever and improve the overall tolerances in this transmission.
SPOON does some work on these things. Does anybody know what they do!
I have also read a lot about cyro gears and stuff like that so any help on this subject would be appreciated as well.
I am going to take the trans out of the car in a little while and I want to build the trans to be bullet proof so that I can do the 8000 rpm 1>2 and 2>3 shift without beating the Synchros and feeling a crunch!
Any help is appreciated!
I had a Boxster S and used to redline it all the time and it shifted like butter!
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Joined: Oct 2005
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the synchros are made of a relatively soft metal. brass i belive. i doubt cyro treating brass would help any.
i have an idea on how to help the synchros slow the gears better but it would be kinda hard and confusing trying to describe it without actually showing you in person. also im just a dumb meatbag, so i dont think my engineering is better then the factory engineers.
i have an idea on how to help the synchros slow the gears better but it would be kinda hard and confusing trying to describe it without actually showing you in person. also im just a dumb meatbag, so i dont think my engineering is better then the factory engineers.
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Joined: Dec 2005
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Pretty common in Evo trannies and there is a guy in town here that builds trans for Evo's and Supras and stuff like that. He uses carbon synchros and sometimes a double synchro for higher hp cars.
I have an '00 with 80k on it and my second makes a little bit of noise when shifted at 9k and I would like to fix this. I want to research companies that make upgrades and do the 3-4 at the same time.
I have an '00 with 80k on it and my second makes a little bit of noise when shifted at 9k and I would like to fix this. I want to research companies that make upgrades and do the 3-4 at the same time.
