Hey guys, i have a 5 spd tranny and 5th gear started to grind(notorious on fd tranny)

is the center section the same as a fd? Is the gearing the same as fd? Is it worth rebuilding a 5 spd or replace?

what are your inputs on this?

 

center sections are the same. 3rd gear is a bit longer in the fd transmission. My 5 speed rx8 trans shifted smoother than my fd transmission.

 

^^^Not internally they aren’t. Also I corrected myself way back when and maybe you missed it; JP and USA RX8 version has same 3rd gear ratio as the FD, but the EUDM RX8 version was different.

The RX8 5-spd is improved version of the FD3 trans with the same/similar multi-pc synchronizer setup as the 6-spd RX8 trans. You definitely want it rather than converting the older one. Synchronizers wear though. If you got it used there’s no way of knowing what abuse it was subject to prior to being in your hands.

https://www.rx7club.com/rotary-car-p...d-rx7-1142443/

I can recommend a quality place to get it rebuilt, but with shipping and services it’s not cheap. Still quite a bit less than a new one ($2600 from Mazda Motorsports), but you can get a used RX8 5-spd for 1/4 - 1/3 the cost of the rebuilder price. If you decide to get a used one I’ll buy that one from you. I need the whole outer bellhousing and casings for a racing dogbox gearset I bought off the Monsterbox 4-rotor FD3 on RX7Club. The internal OE shafts, synchros, and gears are replaced by it. So a bad 5th gear is no bfd for my need. And it will help fund your replacement.

eh crap, you’re in Canaduh. The shipping cost to Texas might kill it for me.
.

 

I'm interested in this subject. Here is what I've found the difference between 5 speed JDM and EUDM gears to be (listed below). Is this consistent with what you guys have found? Is it true that the EUDM 5 speed rx8 does not have the strength of the JDM 5 speed?

Gearbox: EUDM 5 speed rx8
1st - 3.483 (15.48)
2nd - 2.015 (8.95)
3rd - 1.484 (6.59)
4th - 1 (4.44)
5Th - 0.762 (3.39)
R - 3.288
Final drive ratio std: 4.444

Gearbox: JDM 5 speed rx8
1st - 3.483 (15.48)
2nd - 2.015 (8.95)
3rd - 1.391
4th - 1 (4.44)
5th - 0.806
R - 3.288
Final drive ratio std:
4.444

1994 Rx-7 twin-turbo 5 speed
1st - 3.483
2nd - 2.015
3rd - 1.391
4th - 1.000
5th - 0.719

 

Gee, wonder where that came from?

I doubt anyone knows. JDM are easily found. Nobody is importing from EUDM.

I just picked one up from a local JDM importer. One of the nicest I’ve ever seen FS, been looking at them online for a while then found this one only 20 minutes away. It’s definitely used, but I’d be surprised if it has more than 20,000 miles on it if that. Super clean. I almost hate to gut it for installing a racing gear set.

 

To be honest, I searched that information out of google. It was later that day after I made the post that I read through a couple of the rx8 threads and found the same info, DOOH. Goes to show I should search rx8club first. It's clear to me the JDM rx8 5 speed is the way to go. I suppose you can sell the internal gears. I'm sure there are plenty of rew swap people who will be needing them.

 

yeah, it’s been well discussed for quite a while here

https://www.rx8club.com/series-i-maj...setups-225750/


otherwise I’ll likely post up a picture of me throwing them into the trashcan just out of spite; wouldn’t want to ruin my well established rep around here

.

 

I'm trying to replace some parts on my JDM 5 speed. What parts from what car should I be looking for? I need to replace the input and output shaft seals, the reverse and neutral sensors, and the rubber boot where the shifter sits. Thanks

 

They may be the same as the RX7 FD3 5-spd, but you can import the RX8 JDM parts from a supplier in Japan:

https://www.amayama.com/en/catalogs/...transmission-7


most of those seals etc are in the first selection for Manual Transmission Case
.

 

If the reverse and neutral sensors are the same as on the USDM FD 5-speed I probably have those around here somewhere. I also have an FD 5-speed that is good for parts (output shaft is broken but the internals are good).

John

 

supposedly the gears are not as wide in the RX8 version to make room for the additional synchronizer rings, suggesting that it may be weaker than the FD3 trans

it obviously wasn’t expected to be pushed that hard behind an anemic 192 bhp rated Renesis engine …

 

thanks I'll check this website out

Thanks. I will try to source it new first. But used is always an option. I'll take pics and show what they look like

 

If any one needs one pm me. I’m in Portland

 

so what's MaDMaX up to these days?
.

 

To be honest, i just enjoy the car! It drives and behaves like a stock rx8 at light throttle, until you give it the beans! Im sad, i just installed a microsoft surface go tablet in the car to use it as a dash and the damn thing got bricked after a firmware update, good thing i dont need a laptop at all now since the car is pretty on point. Tranny works perfectly, clutch is easy to operate and holds more torque than i need, no engine hiccups. Im happy with it! It could be a bit faster but its plenty right now and i dont stress the engine too much

 

Is this with the rx8 5spd? What clutch and flywheel are you using?

 

i use oem rx8 flywheel, spec stage 3+ clutch for rx8, oem rx8 5 speed, oem drive shaft

 

I’d be reluctant to use the Renesis flywheel on an REW without having the rotating assembly balanced due to the component weight differences, but it must be close enough if you’re using it and not noticing anything

 

Just don't use the RX8 counterweight.... 😀

 

The stock rx8 flywheel has the counterweight built in. Can't add the FD counterweight to that.

 

the manual REW flywheel has it added in too, for the heavier REW rotating components, that was my concern

if it were an aftermarket flywheel then the flywheels are interchangeable between them, but you’d use the REW counterweight with it on an REW engine. The counterweight is different between the previous 13B engines and the Renesis. Therefore my expectation is that the balancing would also be different between the OE REW and Renesis flywheels as well.
.

 

Just my poor morning reading comprehension skills.... never read the stock Thing 😕
I wouldn't use the stock RX8 flywheel... way different weight.... i suppose it would depend if the front was RX8 or REW weight. Might get away with that

 

sounds like old man syndrome

Could be.... but if I recall your up there too 😉

 

Youre right guys, i now know its different but didnt back then. If i had to redo it, id get my rotating assembly balanced.

Still works fine though.

 

somebody edited my post rather than replying to it, the syndrome strikes again.

but I’m way ahead of you Dan.