what is the difference between a na clutch and a turbo clutch?

 

size.

 

NA clutch is 225 mm ( 9.0 incher )
and 22 splines
the pressure plate is mounted from lug blocks situated around the flywheel circumference

the turbo clutch is 240 mm , 9.5 incher
( actually 235mm for s5 and 245 mm for s4, but they interchange )
and is 23 splines
the pressure plate is mounted to a flat faced flywheel
( actually the inner friction face is a few mm higher than the bolting face )

prior to 1983 ( in most markets, HB cosmo has the 225mm clutch in 1981 )
all rx's used a 215mm ( 8.5 incher ) with same 22 splines as the NA
and the friction face is stepped about 5-10 mm lower than the bolting flange face

 

A NA clutch fits a NA transmission, while a TII clutch fits a TII transmission. The important difference is the spline size.

 

wow, thats what i wanted know. you know your stuff. GOOD VERY GOOOOOD.
BUT IM CONFUSED.
i have 88 na aluminum flywheel with the bump ups and i had a aluminum flywheel without the bump ups but it drops down where the clutch friction plate sit but theres no bump ups on the outter edge of the flywheel????
what would you say it is a turbo or non turbo? it fits the the na clutch diameter but once i bolt the clutch down to the flywheel diaphragm splines point towards the flywheel. the not parallel to the flywheel.

every na flywheel ive seen has the bump up on the outter edge of the flywheel but thus one doesnt have the bump ups.
let me know what you think...:

 

sounds like no2 flywheel is in fact for the early rx's and is a 8 1/2 incher
- the splines in the clutch are the same , the ring gear diameter is same,, just one is lug faced ( 9 inch )
other is step faced , no lugs and with the friction surface lower than the bolting flange

you cant really mix and match any parts between any of the three clutch choices
( however both 8.5 and 9.0 setups will suit the same boxes and starters )
despite the fact it LOOKS like your 9 inch clutch disk fits the 8.5 inch flywheel and vichy versa
- definately the pressure plates are different in relation to the step heights between the flange and the friction faces
( as you have found out when you tighten it down )

 

I have a 1987 TII. A few weeks ago I bought what we thought was a turbo clutch/pp from a fellow member. The splines match (23 and the same clutch alignment tool fits this new one and the one I pulled off my car), but the clutch diameter is 8 7/8". The pp mounting points look like the same pattern but with a smaller diameter so it definitely will not bolt to my flywheel, and the pp surface rides 3/8" outside the mounting surface instead of being recessed. I'd like to figure out what car this clutch is supposed to fit, or if the initial supplier mixed up a clutch/pp set or something.

 

Did you ever try to use it ? I wonder what would happen if a Pressure Plate from a different year Rx7 is used with a different year Friction disc and Flywheel ? I know trannie splines are different size and Friction discs would not be interchangeable but just a PP used with a different setup.. Anybody actually start their engine and try to drive like this ? Would it work ?