[flush_ta_death]

well as ive heard and known that the 2002 stock gearbox is pretty weak. i was wondering on how to beef it up without going ppg and stuff. everything ive looked at seems to hit about 4k and up. as ive stated before this isnt for race purpose. just a fun project

 

[oguitar]

Number one thing. Learn how to drive a Bugeye. They are finicky. My supposedly weak AA transmission is going on 110k miles of hard driving. Many people have gotten many more miles then that.

 

[zax]

Well... don't drive like an ass and you should be fine. The "weak" gearbox has been branded as such because of the many abusive AWD launches from popped-collar teenagers.

BUT there is a trick if you're worried. Ever wonder why the Forester XT transmission wasn't branded as "weak" despite having exactly the same gearset as the 2003-2007 WRX with increased torque? The key is the Final Drive ratio of the transmission. Physically modifying the final drive of the transmission requires a different set of differentials and a separate output shaft = pricey. There is a way, however, to effectively "gear down" your WRX without modifying the actual transmission:

How to make your car faster and reduce the stress on your transmission - NASIOC

However, there are a few drawbacks:
1. You'll be pushing higher revs on the highway -- decreased fuel economy will follow.
2. There will be more wheel gap than stock... teenagers aiming for "herrafrush y0!" will cringe at this.
3. Lower non drag-limited top speed
4. Speedometer will read fast and Odometer will read high

BUT, you will put less strain on the tranny and you will get marginally better acceleration.

If this approach isn't for you, be prepared to shell out at least $1200 for a gearset + $1000 for an install. However, if you aren't over 300wtq, I wouldn't be concerned; just drive liberally.

 

[flush_ta_death]

Number one thing. Learn how to drive a Bugeye. They are finicky. My supposedly weak AA transmission is going on 110k miles of hard driving. Many people have gotten many more miles then that.

yeah i got around 110k also. i just hear so many horror stories i was just trying to see some options and stuff.

 

[flush_ta_death]

Well... don't drive like an ass and you should be fine. The "weak" gearbox has been branded as such because of the many abusive AWD launches from popped-collar teenagers.

BUT there is a trick if you're worried. Ever wonder why the Forester XT transmission wasn't branded as "weak" despite having exactly the same gearset as the 2003-2007 WRX with increased torque? The key is the Final Drive ratio of the transmission. Physically modifying the final drive of the transmission requires a different set of differentials and a separate output shaft = pricey. There is a way, however, to effectively "gear down" your WRX without modifying the actual transmission:

How to make your car faster and reduce the stress on your transmission - NASIOC

However, there are a few drawbacks:
1. You'll be pushing higher revs on the highway -- decreased fuel economy will follow.
2. There will be more wheel gap than stock... teenagers aiming for "herrafrush y0!" will cringe at this.
3. Lower non drag-limited top speed
4. Speedometer will read fast and Odometer will read high

BUT, you will put less strain on the tranny and you will get marginally better acceleration.

If this approach isn't for you, be prepared to shell out at least $1200 for a gearset + $1000 for an install. However, if you aren't over 300wtq, I wouldn't be concerned; just drive liberally.

hahhaahhhahaahaha...well a couple questions about that..about how much do you think the differentials and output shaft would cost? and with the wheel gap how will that be affected with coilovers? just have to readjust them to get back to desired height?

and 1200 for a gearset? is that one that could take a beating? everything ive seen was a lot more

 

[zax]

hahhaahhhahaahaha...well a couple questions about that..about how much do you think the differentials and output shaft would cost?

To be honest, you would have to install the diff (including the different half-shafts and different length driveshaft) and rebuild the tranny with a different output shaft. You'd spend less rebuilding the tranny with stronger gears; this is why it's not a very common mod.

with the wheel gap how will that be affected with coilovers? just have to readjust them to get back to desired height?

Theoretically. But remember that the lower profile tire means that you will have more "wheel gap" at the desired ride height.

and 1200 for a gearset? is that one that could take a beating? everything ive seen was a lot more

Yes. You can get STi RA gears or Legacy GT gears for around $1200. They aren't much stronger than a 2003-2007 WRX gearset (if at all), but it's a common modification. I've been loosely toying with the idea -- if my transmission were to meet its unfortunate end -- of investing in a set of STi RA gears and shipping them out for shot-peening and cryo-treatment. That setup should be 30-50% stronger than stock at a lower price-point than other gearsets. The 6spd Evo MR (also known for a "weak" transmission) guys do this since not many Mitsu 6spd gearsets are available.

 

[flush_ta_death]

so the STI gearset is not that much stronger...so why spend the money in buying that when you could go ppg or something.. i feel it corresponds with like doing it right and doing it once rather than replacing and worrying

also you compared the STI gearset to 03-07 WRX gearset. is there a difference in the 02 since it was not included in that and are the 04-07 WRX gearset that much stronger than 02 WRX

 

[zax]

so the STI gearset is not that much stronger...so why spend the money in buying that when you could go ppg or something.. i feel it corresponds with like doing it right and doing it once rather than replacing and worrying

also you compared the STI gearset to 03-07 WRX gearset. is there a difference in the 02 since it was not included in that and are the 04-07 WRX gearset that much stronger than 02 WRX

STi RA gears are 5MT gears from the 1993-2000 STi RANOT the 6MT STi gears in the 2004-current USDM STi.

The 6MT STi gears are much stronger than 2003-2007 WRX gears.

Yes, there is a difference between 2002 and 2003-2007 WRX gears. The 2003-2007 WRX gears are 1mm wider than the 2002 gears. Whether they are "much stronger" is difficult to prove.

 

[flush_ta_death]

ohh okay that really cleared things up. thank you. whats the estimated price range on the 5MT and the 6MT?

and about how much is shot-peening and cryo-treatment?

 

[SD_GR]

Wider gears came in 2002, not 2003. My 2002 has the revision.

 

[zax]

SD makes a good point. Without the transmission code, it's difficult to prove which 2002 WRX and 2003 WRX received the 1mm wider gears. The transmission change came somewhere between MY2002 and MY2003 (some 2002 WRX have the -BA tranny and some 2003 WRX have the -AA tranny)

 

[zax]

http://www.iaperformance.com/product_info.php?manufacturers_id=&products_id=780

 

[Ruh Roh]

i just bought an 02 with 72k miles. trans seem pretty good. never have launched it and probably never will. i do slowly pull out and get on it in first but not really launching it. think the synchros are alittle off because i have to be going really slow to shift into first. its my 2nd 5speed car, i had a 240sx i bought and learned on. have been riding motorcyles for a while now so knew how to shift and everything but was weird using pedals for a clutch and not my hands lol. but all good now. i also rev match my downshifts and actually am really good at it and have like seemless shifts.