I was wondering what 5spd transmission would be a good upgrade to replace the standard 5spd transmission that my 85' Rx7, with a 12A, has now.

u could bolt in a GSL-SE tranny, or with some modifications, a Turbo II tranny works as well. If you not gonna be putting down huge #'s a GSL-SE tranny would be a great upgrade for reliabilty reasons.

[quote name='rexguy' date='Aug 27 2005, 11:47 AM']u could bolt in a GSL-SE tranny, or with some modifications, a Turbo II tranny works as well. If you not gonna be putting down huge #'s a GSL-SE tranny would be a great upgrade for reliabilty reasons.


[/quote]There is no advantage to using the SE box over the 12A box. Or any other n/a box for that matter.



The Turbo II gearbox is the easiest upgrade. You would need a 12A auto counterweight, TII lightened flywheel and clutch. The extension housing needs to be modified to bring the shifter into the correct position. Unless you're going to be running a decent amount of power then it's probably not worth going to the trouble.

[quote name='Fool Boost' date='Aug 28 2005, 06:32 PM']There is no advantage to using the SE box over the 12A box. Or any other n/a box for that matter.



The Turbo II gearbox is the easiest upgrade. You would need a 12A auto counterweight, TII lightened flywheel and clutch. The extension housing needs to be modified to bring the shifter into the correct position. Unless you're going to be running a decent amount of power then it's probably not worth going to the trouble.


[/quote]

you'll also need a custom drive shaft

I had the understanding that the SE box and FC N/A box's shared the design of the RX-3 box (which I also under stand is a stronger design than the 12a box), correct me if I'm wrong but I seem to have read that (or read wrong) a number of times.

[quote name='rexguy' date='Aug 29 2005, 02:00 PM']I had the understanding that the SE box and FC N/A box's shared the design of the RX-3 box (which I also under stand is a stronger design than the 12a box), correct me if I'm wrong but I seem to have read that (or read wrong) a number of times.


[/quote]

the GSL SE gear box is not THAT STRONG compared to a 12A one....... any N/A tranny is gonna take a **** on Joo If you Abuse It Or run more than 200 Hp and drive like a TF&TF Kid https://www.nopistons.com/forums/pub...#>/BURNOUT.gif

[quote name='rexguy' date='Aug 29 2005, 02:00 PM']I had the understanding that the SE box and FC N/A box's shared the design of the RX-3 box (which I also under stand is a stronger design than the 12a box), correct me if I'm wrong but I seem to have read that (or read wrong) a number of times.


[/quote]





The stronger boxes you have heard about are the "r type" boxes of the rx'3 and then the turbo II's. You can tell them by the ribbed cases rather than smooth and the bell housing is removable.



-billy



ReSpeed Rotary Parts

http://www.mrcmfg.com

K, thanks, sorry about the mis-information, glad someone could clear that up for me. And BlownSE, next time try giving me some actual information. I said that the information I stated was what I belived to be factual and if I was wrong to correct me. I didn't asked to be flamed like some F&F newb trying to sound cool. Anyone knows that the Turbo II tranny is stonger than a N/A one and if you refer to my origional post, I said that (albeit not quite as clear as I would have liked in retrospect).

[quote name='rexguy' date='Aug 29 2005, 05:00 PM']I had the understanding that the SE box and FC N/A box's shared the design of the RX-3 box (which I also under stand is a stronger design than the 12a box), correct me if I'm wrong but I seem to have read that (or read wrong) a number of times.


[/quote]





I have found an SE transmission, with 61,000 miles, that has a brand new centerforce clutch coming with it, for a good price. However before I buy this SE box, and swap transmissions, I want to make sure that this will be an easy swap requiring no modifications and that an SE transmission will bolt in perfectly in the place of the standard box.

Out of curiosity's sake, what do you guys break on these transmissions? I've been running a 13BT on an NA gearbox for 3 years. The H gate broke into 3rd gear once, but other than that the only real problem is that the clutch is starting to wear out. This has not been driven lightly by any means, and is the first drivetrain I learned to drive a stick in? So anyhow, whats the weak link in the tranny?

[quote name='RXTek' date='Sep 1 2005, 09:35 PM']Out of curiosity's sake, what do you guys break on these transmissions? I've been running a 13BT on an NA gearbox for 3 years. The H gate broke into 3rd gear once, but other than that the only real problem is that the clutch is starting to wear out. This has not been driven lightly by any means, and is the first drivetrain I learned to drive a stick in? So anyhow, whats the weak link in the tranny?


[/quote]



Well, there is nothing wrong with my current transmission. I'm pretty sure that my clutch is getting ready to go. So since I will have to drop the transmission to replace the clutch, I figure that now is a good time to upgrade transmissions or at least overhaul the one I have now.

[quote name='Rxcalibur' date='Sep 1 2005, 06:15 PM']I have found an SE transmission, with 61,000 miles, that has a brand new centerforce clutch coming with it, for a good price. However before I buy this SE box, and swap transmissions, I want to make sure that this will be an easy swap requiring no modifications and that an SE transmission will bolt in perfectly in the place of the standard box.


[/quote]



It is the same box you have minus maybe the 5th gear ratio.



Learn about it here:

http://members.ij.net/mrmazda/interc...html#TBPATTERN





-billy

Ive heard that the 79-82 626 tranny will work and has very close gear ratios. 5th gear in the T2 tranny seems to tall for a 12A.

http://members.aol.com/solomiata/Drivetrain.html





read the gear ratio tables, you have an 'M' transmission



The M have the smaller input shaft and different output shaft splines (N/A drivelines) and the R type transmissions are the bigger input/output shafts (TII stuff)



as far as I can tell anyways, the tables have all the gear info and info on box strengths/weaknesses

Yesterday I began trouble shooting the transmission to see if I could find a simple answer to why this transmission has been acting up. For starters the gear box was extremely low on fluid, not bone dry but extremely low. So I replenished the fluid and that seemed to fix the problem. No problems with the clutch, no problems shifting through the gears, no grinding or popping out, and smooth acceleration with no bucking while driving up into the higher RPMs.



However, later yesterday evening the problem began to return slowly and today the car will not shift at all. I checked out the parking spaces where to car has been parked, expecting to find that the fluid leaked out but there were no spots, but that doesn't mean that a majority of the fluid didn't leak out into the city streets.



What I can tell you it that I had to move the car this evening. It would not start, or turn over, while in gear (friction plate problem?), in first, second, or reverse, and it would not go into to gear even after double clutching. So I guess I have more of a transmission problem than a clutch problem. I'll go underneath the car tomorrow and look for leaks and replace any lost fluid if its needed. However, if it turns out to be a friction plate problem, or a pressure plate problem, or a synchro problem, I think now would be the time to switch to the SE transmission which is already, ready to be installed. Though, for now I'm pressed for time, so I hope that I can find a fixable leak and that no other damage has been done to the current transmission.

[quote name='Rxcalibur' date='Sep 5 2005, 06:59 PM']What I can tell you it that I had to move the car this evening. It would not start, or turn over, while in gear (friction plate problem?), in first, second, or reverse, and it would not go into to gear even after double clutching.
[/quote]



No,



If it starts and runs OK in neutral, but not any gear, then the clutch is not releasing.



Usually a clutch master cylinder problem. Low or no fluid. Leaking slave cylinder or the like. Much cheaper than a transmission. Have someone operate the clutch pedal while you watch the slave cylinder to see if it is moving.



Lynn E. Hanover

The clutch master cylinder was the first part that came to mind when the Rx7 started to have this problem, since the clutch pedal would go straight to the floor. So I have replaced the clutch master cylinder and the clutch release cylinder because even after replacing and bleeding out the clutch master cylinder, the clutch pedal still remained spongy. Not anymore and this Rx7 lives to shift another day. Thanks