F1blueRx7

iTrader: (5)

What exactly makes this transmission weak, and can it be fixed?

What makes the turbo 2 transmission so different that it cannot be dropped into the n/a drivetrain?

What does hardening the stationary gears do to a transmission, what companies out there can do this, how much does it cost?

Is there some way to switch bell housings or such to switch to a t2 trans?

Thanks

-Mike

Project84

The tranny isn't necessarily weak, its just not as strong as others that are available. The turbo tranny has a ribbed case and other subtle features that stregnthen it more than the N/A tranny. But every tranny has its breaking point.

The turbo tranny isn't different from the N/A as far as being used in a N/A drivetrain, its the clutch/flywheel assembly thats different. The Turbo clutch assembly is bigger around than the N/A stuff. So if you put a turbo motor in a N/A car, the N/A tranny won't fit around the bigger flywheel.

Hardening the stationary gears do nothing to the tranny. The stationary gears are in the motor. It lets them stand up to long periods of high RPM useage. Check out www.racingbeat.com they sell Hardened stationary gears for a decent price.

All the RX-7s transmission bellhousings, gear boxes and tail shaft assemblies can be mixed and match (for example, a 2nd gen gear box can be put between a first gen bellhousing and tail shaft) to get what ever gear ratio in a tranny that will fit in your car. Some Mazda miata tranny parts will work as well. But like I said, the Turbo tranny as a whole will go into the car as is.

Hope I answered all your questions.

F1blueRx7

iTrader: (5)

Well my main complaint is I wanna be able to rip the gears through without so much grinding... Is there anyway to modify the transmission in order to make it stronger?

Are miata gearbox's stronger, are they geared lower?

what miata year/engine style will bolt up?

drago86

Rb makes a clutch disc that allows a t2 tranny without a t2 flywheel, its unsprung however, and you'll still have to get a custom driveshaft made.

Dont shift the tranny fast if its on the way out, youll just make it worse, learn to double clutch upshifts(when you need to shift fast,.. kinda) and downshifts, that should make it last longer. Also switch to redline synthetic, it worked wonders for my tranny. The NA trannys are just wak period, because the never really changed them from the 1st gens and before, so there overloaded with the heavyer FC and the more power.

SureShot

What - you're not running synthetic gear oil already?
That should be the first mod done to any RX-7.

Then - as with any high mileage tranny - short shift to 2nd. (around 6500)
That way the old syncros can keep up.

Here is a short video of what I mean.
link to video

Fingers

Project84! you stole my old sig pic!!! :P

F1blueRx7

iTrader: (5)

Yeah I'm running NEOGear from mazdatrix. The reason I ask is I want to shift rediculously fast, I have a Mazdatrix SS kit installed and I want to be able to shift
when I need to get moving quickly. I saw that pinapple racing offers a miata gearbox into an rx7 n/a transmission... How hard is this swap? has anyone done this themselves?

C. Ludwig

iTrader: (27)

The Miata swap won't give you a stronger box or one that shifts better. The gearing is a bit tighter however. If you're crunching gears it's most likely your synchros have seen better days. You car is 15 years old and most likely has well over 100k on it. Things wear out.

Ni5mo180SX

Im not quite sure on the internal differences of the T2 transmission (r-type) aganist the NA but as pointed out before, the T2 transmission has a larger clutch assembly then the NA which translates to a larger friction surface that can handle the heat better.

Which, in my case, is why I used the NA flywheel on the T2 motor. With my current setup, its making quite a bit of power but my transmission seems to be holding up with no problems as of yet. I replaced the clutch/pp, bearings, seals and fluid (MT90) upon installation of the new engine.

Dak

Also the TII driveshaft has a bigger front yoke and the mounting holes on the rear flange is different so you'll need a custom driveshaft or a TII one with the flange redrilled to fit the N/A rear end.Someone on here said Mazdatrix will now assemble thier aftermarket driveshaft with the replacable u-joints with this setup.Also as previously mentioned you'll need a TII flywheel,and clutch from the series you have and the TII started.