There are teams out there racing 3 rotor RX-8s, am very interested in hearing of any aftermarket changes and/or upgrades made to trannys to handle the extra stresses of racing, and would they be practical for a car used as regular street transportation?

 

3 rotor Rx8s I'd imagine are not starting with the Rx8 tranny b/c they are not starting with a Renesis. Maybe they are running modified Rx7 trannies.

 

They're running $25,000+ sequential racing transmissions; Xtrac, etc.

A new turnkey car is $250k

 

The 3 rotor GT 8's run the EMCO Gears GT-46 transmission. Which is $53,000.00, the axle kit is $12,750.00 and the drive shaft adapter is $2,750.00.

A grand total of $68500!

Also, they are not RX-8's at all...they are a tube framed chassis on wheels with molded body panels that look like an RX-8. Visit Speedsource's site to get a little more info the car itself: http://speedsourceinc.com/index.cfm?...&section=mazda

 

I am still surprised we don't have a solution to upgrade our trannies after 6 years of R&D.

 

The upgrade was the 09 tranny or a modded pre 09 tranny in a 5 speed.

 

Oops, guess I was overconservative on the pricing

there are modifications for the S1 6 speed from Japan

one is a new layshaft with revised first and second gears that make it more close ratio

1st changes from 3.760 to 3.014
2nd changes from 2.269 to 2.062


There are also two options to change 6th gear:

from 0.843 to 0.862
from 0.843 to 0.795


Then there are several builders who can offer services like REM finishing internal parts, setting better tolerances, etc.

None of this is inexpensive though. IMO you're better off with an aftermarket trans if the class rules etc allow it, even over the newer '09 6 speed

 

Your solution to an upgraded transmission is a phone call away. Call up Level Ten www.levelten.com

 

Here's an Idea, why don't you tell us more about yours?

 

I will soon enough i am getting the full specs from level ten in a week or 2. Going into tomorrow for a trans service

 

https://www.rx8club.com/showthread.p...87#post3383987

 

Do like I did and blow it up then have that tranny rebuilt with hard parts...

 

Where could one obtain these harder parts?

 

Fb transmissioin , have a performance tranny for your application make call to mike for your specific car. The 4STB is a good choice
Rgonza

 

I just got my 07 Rx8 back yesterday. I've got a monster transmission now. Starting the process of building up to 500hp. I know it's going to be tough, but I started with the most problematic area of this car. They reinforced all the transmission eternals and put strong 3rd and 4th gears. As well as a lightened flywheel. Cost wasn't horrible.. 4,000, but I was told by the race/performance shop that this should absolutely hold up to 500hp+. I'll let you guys know how things go.

 

Could of just got a JDM RX-8 5pd.
It's the same as a FD trans and I know guys running 5-600rwhp at the track with them.
But it's yo monies
.

 

No thanks.. I'd rather hand build here in the US over a transmission in which I am hopping isn't cheaply made.. I've been through to many Asian built engines and transmissions on my projects. I'm actually still torn between ripping it all out for an LSX swap. Thanks though!

 

Yeah those stupid Asian built engines and transmissions are well known for being unreliable.

 

Like why do they even bother.

 

Stock FD 3rd gear is a notorious weak point and prone to failure. There are plenty of viable options, all of which are rather pricey ranging from around $5K-$20K. If you can use an FD transfer case, an OS Giken gear set would be the cheapest option. If thats not enough for you, you can look into straight cut dog engagement gears from companies like PPG. If you are including yourself in the same group as professional racing cars, then you may need to get yourself a Holinger sequential and call it a day.

$$$ lets you do cool things.

 

Well if you're going to swap gear sets then you might as well stick with the RX8 trans, PPG can set you up

 

There is a peripheral port 3 rotor 450hp time attack car that runs series 2 RX8 gear box.

If you turbo a 3 rotor then you will definately need to look at a stronger box due to the extra torque.

My 12 year old series 1 gear box combines well with my twinscrew supercharger which has almost double the torque of the standard motor.

 

^^That remains to be seen ...

 

all depends on the weak point with rx8 transmission. If the gear is the issue, try it with different series steel. If input/output shaft flex is the issue (like rx7 transmissions), you can get new 300m shafts made by liberty transmission custom for about $600 like they do with rx7 ones.

Most with 20b are going with t56 magnum transmissions-around $3k new on ebay. Some of us are now dabbling with the 370z transmission which is reportedly bombproof to 1000whp... but who really knows..? anyhow, you need to cut out the 370z bell housing with a band saw and put in an adapter plate for our rotary rear iron with auto rx7 bellhousing. Most of these will put the material cost under $5k with clutch if you do it yourself and be pretty reliable even with drag racing situations. I'm personally thinking of doing 370z transmission swap. They are brand new crated on ebay for $1200 or little over $1700 from a dealership. water jet cut adapter plate would be $500.. clutch another $2k.. hydrolic disconnect, new master clutch cylinder, mount made, new driveshaft adapter... another $1k. it can add up... which is why I have multiple FD transmissions sitting in my garage...

 

This is interesting, where did you get this info from?