I know that ingenering is about compromising. ok now somebody tell me why subaru makes there manual transsmision notchy? Is there a strengh/durability factor? Can't subaru make it smooth and silky like honda' flick flick shifters?

please help me understand the complex world of transmissions, thanks

waved

 

The WRX transmission is mated to an AWD drivetrain; this is a very different situation than a FWD or RWD car. Sure, they could put a bulletproof, amazing transmission in the car; Lexus, Audi and Mercedes make great trannys that mate to AWD drivetrains, but then this $22k or $29k car becomes a $33k or $40k car, and has to compete with an entirely different class of automobile...

 

good point, but maybe I am to curious but I would like to know what makes a trans notchy mecanicly speeking.

 

Specifically its a few things your looking at all together that provide you with what you feel.

First you got the control arms. Weight and length make up what you feel here.

Second connected to the fork is the hub which has the synchros. How effective they are is how fast it pops into gear.

Thirdly the gears themselves. How big are the teeth? what are the tolerances involved?

So in summary you have a short throwing large geared tranny with heavy components compared to your tiny lil honda. Sure if we had a soda can of a transmission throwing gears around would be a snap.

Unfortunately the reality is the tranny is alot bigger and beefier to make up for the added stress of one a heck of alot more power and two it being awd thus more strain on the tranny.

Also consider that you can not make a transmission perfect solely on the basis of weight, size, and practicality. Surely we could come up with a transmission that was unbreakable and light but it would prolly only have about 2 gears. Not very usefull eh?

If you want to comprimise a lil weight for ultimate durability in this style transmission i provide you with the insight to get a sti 6 speed. Proven in testing it can take much more than the 5 speed.

 

so basicaly a strongher/more durable the tranny gives a poor feeling because of weight of the parts inside. What is the diference whit the STI 6 sp (stronger=notchyer) ?

 

The STI unit is a hole different story it is slit differently then the regular 5. also the 5 speed has not beened updated in a long time, subaru has been using it for a while. I would venture a guess that a 6 speed will be in the wrx in the nest few years.

 

tanks for the info guys

 

It is true in many ways that the better performance and higher tolerances (in terms of power), the tougher a transmission will be to shift and use. Cushy little extras like syncros, oversize clutches and all the things that make manual transmissions feel nice also, as RoadSpike pointed out, introduce weakness into the transmission. If you took that nice-feeling Honda tranny and asked it to drive four wheels with 220 HP, it would collapse like the proverbial soda can.

The 6MT is definitely an evolved design over the 5MT, and I also agree with the prediction that it might become standard; however, they might also go for a hydraulic-actuated design with paddle shifters, which is becoming a pretty standard feature in the "luxury performance" category -- and, that's what the rally cars use.

Racers use transmissions known as "dogboxes" which do away with syncros, variable-speed clutches and the like -- they are extremely difficult to use for the average joe, but they will take punishment in the extreme (some are tough enough to keep running even if you lose your tranny fluid, so you have a chance to get into the pit and get it filled or changed out).

 

LOL if that were true USDM WRXs would have the strongest transmissions ever! NOT!

jason

 

lol

whats are the cones ex: first gear double cone, second gear triple cone, third double...

 

It refers to the shape of the syncros. Most modern boxes have dual or triple cone syncros on first - third. AFAIK, the WRX has single "collar" type syncros on all gears.

I actually prefer the feel of my WRX box to any Honda I've ever driven. I do not, however, enjoy the random grinding going into first gear from a dead stop.

 

hmmm..just had a thought. why doesn't some company (ie hks/jun/etc...) develop
a non-split case for the wrx. cheaper than an sti swap......