I was wonering if any tests have been done to see the ballpark numbers that the 06 transmission has been able to handle in a WRX.
Does anyone have any inputs from previous experience?

I am looking to be about 320/320 when I am done and want to make sure I get the right equipment and avoid braking anything.

 

To be honest with you, it can really happen when u run stage 2 on a wrx. I mean it has happened to ppl that way, but then some have made 300whp. But Its really all that TQ that is puttin all the shockload on everything causing it to go.

For example, buddy of mine 06 WRX TR with a VF39 Turbo swap, and running the Cobb OTS maps, doing a pull and a clean shift to thrid, and all of a sudden 3rd gear is gone.

Some may say its driver, but IMHO its both driver and just a matter of time will all the TQ.

 

i think its got a lot to do with the driver.

 

ONce you understand the internal construction of the 5MT you realize quickly why they rip through gears so fast. The gears aren't really the problem, although the helical arrangement doesn't help. The shaft that the grears ride on acually deflects within the casing. The defection is a result of the helical configuration and excessive torque load. I think a straight cut 1-3 and helical 4,5, is probably your best option in terms of rebuilding a 5MT for high torque. The 6mt is a totally different animal. It doesn't suffer from the same deflection because of addition reinforcement of the casing. to sum it up if your running high torque in a 5MT it is going to break. It's part of modding and should be planned for.

 

thanks. I am looking to put in a stronger clutch and see how that does. When I get all my parts put in I will definitely bring up the trannsmision and will get the right stuff so I dont break things and have unneccassary expenses.

 

The clutch will help transmit that torque, but it won't save your driveline. If your going to continue to work with the 5MT get a street clutch, the larger torque dampening springs will save your tranny. Racing style clutch is disaster for a street driven car. The ACT holds power levels very well, it has a nice stiff feel.

 

thanks bro! I was looking at the ACT clutches.

 

good info
how much will it cost to get a 6 speed compared to rebuild the 5 to be stronger?

 

I have seen 6MT from 3500 to 5000, plus installation
the only upgrade to a 5MT I have seen is the RA gears, but heard they are not much better than the 06 5MT. those are like 1250

 

How have you not heard of PPG?

http://www.ppgearbox.com.au/

It does depend on the car though. If you want to track the car then a 6 speed may be better for you. If you are street driven and maybe autocross a bit then the 5 speed PPG box would be great.

PPG's are virtually indestructible. There are a lot of people running huge horsepower number on these gears. But they come at a price. PPG's 1-4 usually run about 5k. The cool thing is you can run straight cuts or helical or both (1 and 2 straight cut is popular with the rest being helical to cut down on noise). There is a bit of downtime on these but in my opinion well worth it.

I don't have them but they are the only gearbox upgrade I would buy. Go browse NASIOC for results and power levels with them.

 

i have a friend who is tuned at 330wtq and his tranny is all good, but then again stock wrx trannies have blown too, i personally think there is something wrong with some trannies and not with others!

my car has been on stage 2 for at least 50k and still fine!

 

True the 03-05 have the same width as RA Gears.

I also read that 06-07 has a lower final drive which causes an increase in shockload.

http://forums.nasioc.com/forums/showthread.php?t=665334

 

Yes, the 06-07's have the 3.70 FD instead of 3.90 and this puts more stress on the gears. 06-07 WRX seem to have a lot of problems with 3rd gear once they go stage 2 or higher.

Alex...