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Old 06-28-2001, 01:46 AM   #1
Clegg
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Default Performance upgrades wiht an Auto

Just looking at possible upgrades like the cobb tuning and such, Phase one or two, before I go and bug them, I was just currious if anyone here knows if its able to be done on a AT Tranny?

What are the stock 02 2.5RS Auto's rated to for HP? 192HP from the Phase 2 upgrade would be nice, but will I rip the lil auto to pieces if I take it to the quarter mile to see how it does?


Also Anyone have any info on what speed shifting an auto ( you can lock the gears down to use the full power band then let them shift into the next gear at 4500 - 5000 RPM instead of 3500 where they want to. ) What it would damage or how bad that is for the auto?

this is a daily driver car into a downtown daily in traffic, so I got the auto for that reason. but I want to have some fun with it and put some nice tech mods on the engine. Just dont want to risk torching my lil AT.
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Old 06-28-2001, 08:50 AM   #2
RS ING
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Well I have the phase one kit and was very close to doing the phase two but I couldn't justify the money for the 6-7HP at the time. I bought a COBB TUNED AUTOMATIC(don't ask me why) and at no time during the ordering process did they tell me that I couldn't get the phase two because of the tranny.

The only item that I couldn't finagale out of Cobb was the automatic shift kit (to harden up the shifts) as this would be a tricky item to defend against a warrenty problem down the road if there were ever a tranny problem.
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Old 06-28-2001, 10:19 AM   #3
Clegg
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I havent seen an automatic shift kit around, It would be nice to change the ratio's a lil bit while increasing the engines HP.

would make for a more efficent use of the HP above the stock setup.

I know there are specs around for the HP rating for the MT, but I am looking for the max HP tollerances for the Auto. I know the WRX has a more expensive Auto ( if you order it with your car), Currious what the differences is between them? Between the MY02 2.5RS AT and the WRX AT
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Old 06-28-2001, 12:34 PM   #4
RS ING
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The shifter kit is just something that makes it shift harder(ie faster shifting). Talk to Cobb tuning about it. I haven't heard of them selling a kit yet but it is very doable and cheap too. I had a descussion about it with Trey back in Feb when my car was being worked on before I bought it. Frank
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Old 06-28-2001, 12:42 PM   #5
ImprezedRS
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The only difference between the WRX auto and 2.5RS auto is that the WRX has a constant 45/65 power split and the 2.5RS has the 90/10 split which changes from front to rear.
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Old 06-28-2001, 01:21 PM   #6
Clegg
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that caused by the LSD in the tranny? Cause a 45/65 ( wiich is 110% btw.. heheheh) would be damn nice. 90/10 is damn weak I think. but thats just me.

LSD = limited slip diff, didnt need people to think I was talking about putting drugs in a tranny
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Old 06-28-2001, 03:09 PM   #7
Silver2000RS
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I suggest that you install a transmission cooler before you go to the track.
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Old 06-28-2001, 03:16 PM   #8
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Quote:
Originally posted by Silver2000RS
I suggest that you install a transmission cooler before you go to the track.
Yeh already thought about that. Does the car have any tranny cooler on its own?
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Old 06-29-2001, 10:44 AM   #9
Willman67
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Default AT mods

There is a group of WRX with AT owners that have been working on performance mods. Check out RIFTSWRX for his posts...he also has a website with pics and instructions for an AT cooler install...its a Hayden model 403.....were also working on an upgraded torque converter, valve body mods and even tranny computer tweaks. Cobb will tell you if you call them that the Subaru Auto tranny is more resilient than the MT and will take more performance (HP) mods.

Wm
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Old 06-29-2001, 11:22 AM   #10
iBlueVirus
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yay! more good new for auto people!
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Old 06-29-2001, 11:23 AM   #11
Clegg
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Yeh the Valve body re-cal, the new TCU, and the tranny cooler all sound like great things, and not too expensive to give you a bullet proof and almost Manual tranny fast AT.

But then again... the whole warranty thing comes into play then
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Old 06-29-2001, 02:08 PM   #12
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Default Almost?

Quote:
Originally posted by Clegg
Yeh the Valve body re-cal, the new TCU, and the tranny cooler all sound like great things, and not too expensive to give you a bullet proof and almost Manual tranny fast AT.

But then again... the whole warranty thing comes into play then
What exactly do you mean by "almost Manual tranny fast AT"? Off the starting line, shifting through the gears or something else? Just curious!
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Old 06-29-2001, 02:57 PM   #13
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Supposively it will rival the Manual Tranny's in all of the above. By controling hte lock up of the torque converter better, and making the shifts harder. It still wont shift as fast as the MT, and also doesnt have a nice clutch to slip in with, so it will never be AS fast. But it will be close.

Still the best tool for shifiting is a person. The car may THINK it knows when to shift, but a person KNOWS when it feels right.
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Old 06-29-2001, 04:27 PM   #14
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Arrow welll.......

The AT is way stronger than the current MT. I read on post in here once that the AT was able to stand up 420hp IIRC. You can also get a Level 10 work up on the AT. Send Kevin Thomas an email or PM. He is renowned for his AT. He drags his OBS and consistently beats “faster” cars.

90/10 – 45/65 debate is basically a myth. In the pre-02 AT the split was 90/10 under ideal conditions, by standing on the gas from either a stop or while rolling and causing the car to downshift while make the transfer almost 40/60 in the AT. The MT is always 50/50. The newer AT is more sophisticated than this one, that is where the 45/65 comes from, the MT is still 50/50. Remember the MT is a viscous LSD, or mechanical and the AT is an electronic VTD (variable torque distribution).

Hope that helps.

-brian-
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Old 06-29-2001, 07:49 PM   #15
inpreza kid
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ok, i drive a auto RS and there is no way the tranny can hold up to 420hp. it can probably take around 250hp maybe less at the flyweel. i don't know how much HP kevin thomas was putting out at the flyweel but it wasn't anywhere near 420hp and his tranny blew on him.
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Old 06-29-2001, 11:20 PM   #16
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420 sounded incredibly high
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Old 06-30-2001, 12:08 AM   #17
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Kevin Thomas used NOS plus a turbo. Even though he wasnt even near 420hp he worked that tranny HARD. If you work your manual tranny as hard as he did his auto with everything stock youll break it too.

Also about the tranny cooler, im not sure you really need it. I have a tranny temp gauge and my tranny has only hit 180degrees F once and that was in some bad traffic for a long time. I also drove the car for like 370miles and the temps on the tranny were around 125-150. I'm also pretty sure the temps when you need to worry are like 250F, but please correct me if I'm wrong.

The stock auto tranny can take a crap load of power before it dies under normal driving.
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Old 06-30-2001, 07:32 AM   #18
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Default Rally Knight?

The AT can take a lot of HP and with a couple of mods, it can take the 420HP mentioned earlier. That number comes from a guy that rally races a modded RS w/ a modded 4EAT. I think the guy's name is Rally Knight on the I-Club, but I'm not too sure. Anyway, I saw him rallying on SpeedVision.
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Old 06-30-2001, 09:03 AM   #19
ej25wagon
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keep one thing in mind.....a well tuned auto will ALWAYS shift faster than a manual...and if your running a turbo...the turbo will never come off boost in between gears !...I must admit tho that a manual is more fun to drive .....

I used to drag race muscle cars ( why oh why did I do that? )
the auto equipped cars were always faster when driven right...and an auto is easier in the rest of the drive train...less shock to things like CV joint and universal joints...
and it's not the HP you have to worry about with oyur tranny...manual or auto....it;s the engine's torque output you need to worry about
now if only I could find some vavle body mods to make to mine !!
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