its mazda everythings the same, except fot the outer diameter.

mike

 

Thanks for the info guys! By the way, a 215mm disk can be used in place of a 225mm disk. Only difference is the outer diameter afaik. Look here for a pic of pieces of a dead 215mm disk used in an REPU's 225mm flywheel: http://www.geocities.com/cd23c/cars.html#rick (I'll take more pics of the rest of it maybe later today)

I was thinking of getting an RB T2 light steel flywheel so I could install it on any engine with a counterweight and a 225mm SS HD disk. I'm thinking the ribcase tranny is probably strong enough to not break, even with a 225m disk. It's got the same gear ratios as a '74 REPU ribcase so I'm assuming it's got the same internals and will be plenty strong. It'll probably handle a 20B if it's NA.

 

mazda only has 4 rwd manual trannies. the m box which debuted in the 78 rx-7, and they use in all the 2wd na or 4 cyl cars. then there is the r box which debuted in the 1970 rx-2, and they use in all the 4wd, 6cyl or turbo cars. then there is the 6 speed miata tranny. the last is the "split case" used in the r100/1200 cars

mike

 

M for sMooth case trannies and R for Ribcase trannies. That's pretty cool!

Let's see, hmm... I think it was Mazdatrix whom suggests the smoothcase trannies can handle up to 200HP but become less reliable at anything higher. I'm not sure how much torque they'll take, but if the power is applied in a smooth way (no clutch dumping at 6k RPM hehe) they ought to live above 200HP for a while.

The ribcase trannies have always been stronger, but how much above 200HP will they take? If the internals from the '70s are similar to the T2's internals, they ought to handle a forced induction 20B if it's not boosted too much. Thoughts?

 

We've kinda determined that puck clutches are deadly to smoothcase trannies, at least in GSL-SEs

 

And I thought the GSL-SE trannies were at least sorta strong. Heh, well I'll be on the lookout for a good 5 speed ribcase tranny for my REPU (and everything else) now. Forget about the smoothcase trannies; they're not worth it.

 

The GSL-SE tranny is absolutely no different than the standard tranny for the 84-85 RX7 (IE no stronger). The ONLY difference between the two is the 5th gear ratio. All the internals for 1-4 gears are identical. I know this because I rebuilt my GSL-SE tranny.

I have always been told that every RX7 tranny was at the limit for power in their respective cars. NA tranny about 160 was just a bit too much, TII tranny 200 hp was just acceptable, TwinTurbo 255hp was too much for the synchros.

It is only a matter of time and the tranny will be the weakest link in a 20B conversion.

On another note, would the 20B auto tranny be better or is it identical to the Auto Tranny in the 3rd generation? Does anybody know this? Can they be swapped out? What about the A/T computer controller?

Tim

 

I'd like to know what the difference is between the CD and JC Cosmo autos as far as power handling. The CD auto is what I'll be using at first and it's rumoured to handle at least 400HP on a boosted 13B. It'll sure be fun to find out for sure

One thing about using a 215mm disk in an REPU flywheel, the splined center of the disk ended up rubbing the eccentric shaft in my friend's REPU. No damage to the eccentric shaft, but the splined center of the disk looks funny. So there is a slight problem with it (other than how easily it grenaded under power, hehe), but in an emergency, it's just fine to use.

 

I dont know about the auto being better or not. But To dredge up an old point a T56 tranny can handle the torque of one of these monsters. I have several friends with 650-700 hp LS1 V8s and thier 6 speeds are holding up very nicely. So we would just need to locate a compatible bell housing or an adapter.

 

I was told by a camaro guy that the bolt pattern for a T5 bellhousing and the bolt pattern for a chevy aftermarket T56 bellhousing is the same. Sooooooooooo therefore, in theory, you would be able to use the adaptor kit from Kennedy Engineering that allows you to bolt up the T5 to any rotary and bolt up the T56
If anyone does this please let me know, I havent had the funds to test it out yet.
Good Luck guys!

 

Well I don't know much about adaptor kits bust...
If a T5 or a T56 bolt pattern is the same,t hen one would think they would bolt up. But, couldn't the length of the bellhousings be different, thefore it wouldn't work?

I don't really know, just what I think.

 

Anyone have the link to Kennedy Engeneering?

 

http://www.kennedyeng.com/

 

i emailed kennedy engineering a while back and asked them aboot the T56 and the T5, all they had to say was that they didnt know anything aboot the T56's, so....
I may still have the emails that i got from them and the camaro guy, lemme check.

 

Heres what Kennedy said in various emails...

"I do not know if the T-56 has a different shape. The Mustang T-5 is narrow enough near the bottom on one side that it leaves room for a starter motor."
"Two different size clutches are used by Mazda. Stock Ford discs are
available to fit. We provide a new pilot bushing, the Ford clutch release
bearing is not changed. The trans sits on an angle so the shifter lever
must be bent. A new speed-o-cable will probably be needed, and the
crossmember must be modified."
"Its $300.00 and it is kit #9900."

Then this was my convo with the camaro guy...

I wrote:
Hey, I was just on your website and noticed that you have a link to a place with an adaptor kit for the T-5 transmission to hook up to the Mazda Rotary engine. I was wondering if you have or know of someone who has a kit for the T-56 transmission to hook up to the Mazda Rotary engine and make it all work (ie: bellhousing adaptor, clutch and flywheel adaptor or something, etc.)
If you could get back to me that would be great.
Thanks

Response:
"The aftermarket version of the T-56 for Chevy applications uses the same bellhousing pattern and clutch style as the T-5 does, which would allow you to use the Kennedy T-5 adapter with that version of the T-56"

There yah have it.

 

Ford T5s have a different trans-to-bellthousing pattern than Chevy T5s.

 

That could pose a problem.

 

The guy said that you could use the Kennedy T5 adaptor kit with the aftermarket chevy T56... I have given up on researching this because it makes me depressed that I cant buy and try it out, so others pick up where I left off and try and find out if its actually true!
Lates

 

The Kennedy adapter mates a Ford T5 to the Mazda bellhousing.

The thing is, the Ford T5 pattern is unique... it's nothing like the standard Chevy Muncie/Nash/Borg-Warner pattern used from the 50s/60s up to the last of the T5-equipped Camaros. It's also nothing like the Toploader-pattern trannies used on previous Fords.

To make matters worse, the 5-speed used behind 3.8l Camabirds uses a Ford-pattern T5 and not Chevy-pattern!

 

What about a G-force Tranny with an H pattern shifter? They make a 13B adapter plate. Would this work on a 20B?

 

will a race organization let you race with 5 out 7 bellhousing bolts?
the 20b is the same as an automatic fd, and it is 2 bolts off of the 74+ bellousing pattern

mike

 

I wonder if you could weld some extra drilled pieces of aluminum to the tranny, for the extra bolts?