but didnt really feel like asking.



so mazda has 3.5 different 6 speed transmissions, based on 2 designs. i'll use part numbers, they are more accesable`



the Y box. these are made by aiasin (sp?) and i think also are put into 350z/g35's among others.



y601: this transmission is from the 99 miatas, it was designed to fit exactly in place of the miata 5 speed, and it does, with the exception of 1 starter bolt. it uses the small, na style input and output shafts, and a gear driven speedometer.



y602: same as the 601, but with hardened gears and input shaft for the mazdaspeed miata's



y610: this is the rx8 transmission. its similar to the miata trans but uses the larger turbo style input and outputs, also a turbo style clutch. the rx8 does not have a speedometer drive, as it uses the abs sensors. shipping wieght of a new rx8 trans is 206kg. we have one apart right now, its pretty beefy inside, pics to follow....



the 2006+ miata uses a P601 transmission, it is based from the 94-current ford ranger transmission, which is built by mazda. not much info about this one yet, the 25 hour race cars all suffered shift fork failure, and theres no rotary bellhousing

I have many questions.



First and foremost, 206kg shipping weight? Does the transmission come with an engine attached or do they just use a lead-casket shipping container? I don't think even WRX STi transmissions weigh that much, and they have more internal shafting and two differentials to boot.



Second, is the design such that the bellhousing portion can be interchanged between the Miata unit and the RX-8 unit? The front bearing carrier and throwout bearing sleeve would have to stay with the transmission due to the input size difference, but the upshot would be the ability to mate the 6 speed to a non turbo flywheel, assuming that the starter situation can be worked out.



Further questions to be postponed pending further information...

had to have been a typo. i pulled the rx8 tranny out of the trunk of my beater car with the greatest of ease.



but since we'r eon the subject, i have to shamelessly plug that i have an rx8 6-speed tranny for sale right now https://www.nopistons.com/forums/pub...IR#>/smile.png

i looked, the fron seal and bearings are the same between the miata and rx8 versions, so it would appear that you can put the rx8 bellhousing (it is available seperate) onto the miata trans, and it should go into an NA car.

how much?



just for giggles a shiny new one; dealer cost is $2295, which is the same as any other new mazda transmission....

figured i'd start it out at a little less than half that.



1200 obo. it has the shifter and the slave cylinder too.



i was gonna use it in a first gen or fc, but i've decided to reallocate the funds for the fd's suspension. 140k on the chassis....imma do AAAAAALLLLLLLLLLLLLLLLLL the bushings.

Mike,



Do you have dimensions for the rx8 tranny? Is it the same length as the FC turbo ones? Does it share more similarity with the FC TIIs or the FD tranny? What about the bell housing? Is it 13BT / 13B-RE / 13B-REW compatible?



BTW gear ratios are (if anyone was wondering)

1st: 3.358

2nd: 2.060

3rd: 1.404

4th: 1.000

5th: 0.713

6th: 0.582



final drive: 4.300

S5TII ratios are:



1st: 3.483

2nd: 2.015

3rd: 1.391

4th: 1.000

5th: 0.719



In terms of upgrade without modifying the gearsets (can you get different gears ratios)



It looks like it will be a crappy upgrade. For turbo guys. TII 1st gear seems better since it's shorter. For road racing you never use 1st. It may be better for the autox guys if you autox a TII since you can stay in 1st longer. 2nd gear seems close, but the TII has a taller 2nd. Could be better since we can't rev to 9000. We can only really do 7000. That makes a difference. 3rd gear on the rx8 will be way way too short for TIIs. 3rd and 4th is where most of the time is spent on a road course. With the rx8 you would have to shift into 4th too soon.



After that the rx8 tranny is useless for racing. You don't need two overdrive gears for racing.



If you could get gearsets for the thing it may be worthwhile. Then you can make 6th the only overdrive gear. You may be able to use 3rd, 4th, and 5th more effectively.



That is my 2 cents. Right now to me it seems like the rx8 tranny is only good if you can run 9000 rpms or you want to be the 1st on the block.

it's very dimensionally similar to the fd tranny.



the 8 tranny looks to be just a few cm longer and the ppf bolts don't quite like up, but it should be very easy to pop a 5 speed in an 8, or the 6-speed in an fd (assuming you didn't like power). i'll measure them eventually, but my eyeballs tell me it's gonna be an easy conversion.



and the driveshaft fits the fd tranny too https://www.nopistons.com/forums/pub...IR#>/smile.png[[atta[attachment=38503:attachment]chmentid=38504]

I destroyed 2 of them.. mostly because the Rx8 is a bit heavy.. to much weight being launched at redline with a 1.9, 2.0 sixty foot mark..