what year wrx? 02s are basically as strong as rs trannies. remember you are going from 4.11 to 3.54 so you have to change the diff. youre loosing alot of off the line speed.

 

I don't follow?? So are you saying either way I need to change the rear diff?

 

Your title confused him. The rs tranny will work fine as long as you dont slam gears or launch WOT. he was saying if you switch to a wrx tranny you have to switch the diff. RS is 4.11 and i believe the WRX is 3.7. And us a clutch matching the tranny not the engine.

 

so i Would be buying RS tranny parts ??

 

Your title and your question are COMPLETE opposites.

If you put in a wrx engine, then yes, you can continue to use your rs transmission. Just don't treat it like shit. You would need to keep using RS tranny parts, yes, as well as an RS clutch.

 

Thank you and sorry for the confusion. Can you tell me exactly why I can't beat on it? Whats the differences between tranny's?

 

Can you tell me exactly why I can't beat on it?

Because you'll break it.

 

Well i'm looking into doing the same thing hopefully by next summer. And just my .02 here.

But if you're going to cheap out and not get the WRX tranny so that you afford other mods to beef up the motor then you're going to throw gears and then have to rebuild after it's all said and done.

The RS tranny wasn't designed to sustain as much HP and Tq thrown at it as was the WRX tranny. Not to mention like what was posted above the differentials were different sizes between the 2 tranny's. Hence the WRX will have a faster launch and will hold up longer to the abuse you'll no doubt give to it. Be serious with yourself for a minute. If you're doing a swap, you're going to rip on it. If you're going to rip on it then build it right so you can.

So basically what i'm trying to say is this. If you're going to do it; then save your money and don't cut corners or you WILL regret it.

 

No he wont regret it, an RS tranny can hold 300hp / 300tq before it shreds the case like an orange if you're not careful.

A WRX tranny is NOT an STi tranny, the case is still made out of glass. If you beat the piss out of it, itll come back to bite you in the ass just like the RS tranny will if you drive it like a WRX owner.


Do you know how gearing works?

Besides, RS Diff > WRX Diff

Impreza 2.5RS models:

Manual transmission gear ratios:
1st - 3.545
2nd - 2.111
3rd - 1.448
4th - 1.088
5th - 0.780
reverse - 3.333
final drive ratio - 4.11

WRX 2.0l models:

Manual transmission gear ratios:
1st - 3.454
2nd - 1.947
3rd - 1.366
4th - 0.972
5th - 0.738
reverse - 3.333
final drive ratio - 3.90

 

are the WRX ratio's taller(long) or shorter for better accel then the RS?

 

the wrx has long gears other than reverse. The wrx will accelerator slower than an rs tranny but with wrx you will have to shift alittle less and have better fuel economy. It matter what kind of driving you do to decide what one is better and also the 02-04 wrx tranny from what I read are not any stronger but 05 and up are.

 

im running a 2003 wrx motor on a 2001 rs tranny and diffs and light flywheel and pullies. all i did was upgrade the clutch and its running great. just have to shift smooth but it still holds up under hard driving too, but i dont beat it all day everyday. im gonna say you'll be fine.

 

There is no significant difference in the composite of the gears between the WRX and RS. Essentially, if you took a brand new RS trans and pitted against a brand new WRX trans, you could damage them in an equal manner.

The RS trans (w/ swap) is generally regarded as more fun whereas as the WRX trans is bit less.

In the end, driver skill is the main factor in determining the life of your trans. You can make 300 whp/tq (as I did) and drive it spirited with no issues. Launch badly or mis-shift and it's buh-bye. The same can be said in a N/A RS.

 

There is no significant difference in the composite of the gears between the WRX and RS.

Thank you.

One day, if we're lucky within about 10 years, people will finally stop saying that the RS tranny is so much weaker than the WRX one.

It isn't. The RS tranny just has shorter gearing, more similar to the overseas WRX. The USDM WRX had taller gears.

The materials are NO different.

Now, if you have an RS tranny with 200K miles on it, vs. a WRX tranny with 20K on it... assuming the WRX tranny wasn't abused, then yes I'd say the WRX one will last longer. But based solely on construction, THERE IS NO DIFFERENCE.

 

mine is good so far only my synchros are going out.....i'm preatty sure that my (3-4 synchro) was going bad prior to swap. make sure your tranny is solid and perfect. take care of it (fluid change and good driving) i used act hdr4 clutch assy got it new on ebay for around 420 you can use act hd00 as its not as aggressive,......because aggressive clutch sucks in traffic. oh and synchro is 250-300 at subaru dealer, then the main shaft and counter shaft bearings are around 80-100 and seals are around 15-20.....basicly if it blows just find one at junk yard. also DO NOT install short throw shifter.

 

also DO NOT install short throw shifter.

I had a Kartboy SS and had zero issues. Changing the fulcrum of the shifter has nothing to do with the gears. Now if you're talking about the enitre shift linkage, then I still don't see how that affects the gears. Again, it all depends on the driver.

 

rs tranny is more fun to drive around the town....wrx tranny would probably better for frequent highway driving and gas economy. you only need to decide what you do most.

 

First someone saying a WRX tranny is better than an RS tranny when the metallurgical composition is the same, and not having the slightest clue on how gear ratios work.

Now a debate on short shifters? They dont hurt ANYTHING, not the tranny, rims, brakes, seats, steering wheel, turn signals, headlights, ebrake, the intermittent wiper assembly, or any other part of anything remotely close to resembling a car.


The only thing that WILL hurt any part of your AWD car (or any car for that matter), is a driver who doesnt pay respect to the vehicle. Dont drive to beat the hell out of it, and itll last as long as you.

People figure that if they install a short shifter, they can drop the clutch faster, and keep going and hit VTEC sooner, this is incorrect.

 

This thread is incredible.

IMO, the gearing in the RS tranny is about as perfect as you can get for a 5 speed. Maybe if the 1st was taller, allowing the rest to be closer. As it is, you have very close ratios in 1st-3rd, with 4th opening up a little, and 5th being high enough to be a good cruising gear but not too high. I think Subaru handicapped the WRX with tall gear ratios, among other things.

 

Kartboy isn't lying. Tom knows his shit.

 

Kartboy isn't lying. Tom knows his shit.

I know, I've met Tom...he's shown me the extensive process they go through for coming up with the design.