Welcome to the North American Subaru Impreza Owners Club Friday August 1, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Archives > NASIOC Archives > General Forum Archive

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
 
 
Thread Tools Display Modes
Old 07-27-2000, 08:51 PM   #1
griffin
Scooby Newbie
 
Member#: 1387
Join Date: Apr 2000
Location: MN
Vehicle:
. 2007 STI Black
2001 S2000 Black

Post how bad for auto tranny is brake launching?

How bad is it on the tranny when you brake launch an automatic from 3k rpm?

This is with a 2000 2.5RS.

* Registered users of the site do not see these ads.
griffin is offline  
Old 07-27-2000, 08:54 PM   #2
Fitz
Scooby Guru
 
Member#: 1426
Join Date: May 2000
Chapter/Region: NESIC
Location: Goffstown, NH
Vehicle:
'07 335xi, '07 ZX6R
SV650 Race Bike

Post

It's bad for automatic transmissions in general. I guess what it comes down to is if the trannie in the 2.5RS can handle it and how often?

Fitz
Fitz is offline  
Old 07-27-2000, 09:26 PM   #3
griffin
Scooby Newbie
 
Member#: 1387
Join Date: Apr 2000
Location: MN
Vehicle:
. 2007 STI Black
2001 S2000 Black

Post

Then it comes down to, what breaks, is it expensive, and is there any beefier part I could throw in to prevent it?

Its not very often, I probably have done it about 5 times in the last 3 months. I just am interested in how bad it really is.
griffin is offline  
Old 07-27-2000, 09:27 PM   #4
Overtime
Scooby Specialist
 
Member#: 1346
Join Date: Apr 2000
Post

I think (note, THINK) the autos in the RS are as tough as they come.

They're used in Fuji's trucks and can withstand 600hp...so I'm sure they can withstand some powershifting every now and then.

I don't think you need to worry. Besides, when it craps out, you can swap in a 5 speed!
Overtime is offline  
Old 07-27-2000, 09:29 PM   #5
RidinLow
Scooby Guru
 
Member#: 329
Join Date: Sep 1999
Chapter/Region: Tri-State
Location: NJ
Vehicle:
1995 325i
Arctic Gray

Post

Just don't sit there doing it for a long period of time or you'll start to boil the tranny fluid.
RidinLow is offline  
Old 07-27-2000, 09:30 PM   #6
MPREZYA
SCIC
Moderator
 
Member#: 85
Join Date: Jul 1999
Chapter/Region: SCIC
Location: www.themonkeystrunk.com
Post

The best launch by doing that comes from @2000-2200K other wise you will bog. That and it won't cause too much damage if used sparingly.
Rich
MPREZYA is offline  
Old 07-27-2000, 09:54 PM   #7
griffin
Scooby Newbie
 
Member#: 1387
Join Date: Apr 2000
Location: MN
Vehicle:
. 2007 STI Black
2001 S2000 Black

Post

Sounds reasonable.

MPREZYA I would guess I left off the brake at about 2600-3000rpm today. Caught my friend in is talon tsi awd by surprise thats for sure. Those things are fast once their turbos spool, but off the line stock, no chance.

We dont race fast because to dangerous, to expensive, so the impreza does quite well in the 0-45mph against it. After that I have my doubts.
griffin is offline  
Old 07-27-2000, 10:05 PM   #8
MPREZYA
SCIC
Moderator
 
Member#: 85
Join Date: Jul 1999
Chapter/Region: SCIC
Location: www.themonkeystrunk.com
Post

Myself and Keving Thomas (turbo 2.2L auto OBS) talked alot about this and also Flat4 (if he is still around) mentioned that he was about threw with his Torque Converter from high RPM launches in his automatic turbo. Myself and Keving agreed @2k was best and didn't risk too much damage from repeated use and no bog off the line or chatter from the TC goign crazy.
Rich
MPREZYA is offline  
Old 07-28-2000, 05:54 PM   #9
garface
Scooby Guru
 
Member#: 1581
Join Date: Jun 2000
Chapter/Region: Tri-State
Location: yonkers, ny
Vehicle:
MY00 RS/STi7
MY01 RS Both Silverthorne

Post

Can someone explain exactly what this technique involves? If it is just braking with your left while revving with your right, I have tried this and the car lurches forward, can my brakes just not hold it or should I push harder on the brake?
garface is offline  
Old 07-28-2000, 06:11 PM   #10
griffin
Scooby Newbie
 
Member#: 1387
Join Date: Apr 2000
Location: MN
Vehicle:
. 2007 STI Black
2001 S2000 Black

Post

This is my technique.

Push the brake to the floor. Stick the gas about 75% down let off brake at 2500-3000rpm and then get on the gas. I try to get it so I do not have to let off 75% gas, so the needle just keeps going. Not stop at 2500-3000 and rev back and forth.

I will probably let off at a lower rpm now that ive read all this, and not do it that often. But that technique above worked alright for me so far.
griffin is offline  
Old 07-28-2000, 08:10 PM   #11
Imprezer
Dynamic Uno
 
Member#: 1
Join Date: Jun 1999
Chapter/Region: BAIC
Location: Alameda, CA
Vehicle:
2011 Impreza WRX STi
Black

Post

As long as you don't fry your tranny fluid by power braking for too long at one time, you are ok. And after you do it, let it cool down afterwards.
Imprezer is offline  
Old 07-28-2000, 09:34 PM   #12
BryanH
Scooby Guru
 
Member#: 993
Join Date: Feb 2000
Chapter/Region: MAIC
Location: nova
Post

This is something we used to do to get our cars moving down the strip a little faster when I was driving my old GTO

But a couple of pieces of advice:

1. Keep a VERY VERY VERY close eye on the condition of your tranny fluid. It WILL go bad sooner than normal with you doing this.

2. Find the rev point where your stall converter is engaged and rev easily to this point. You don't need to have the throttle 75% depressed to get to this point!!! Ease the engine to this point!! You don't want to be throwing a lot of extra torque against the torque converter when it won't give you any better results. When you get to this point try not to hold it there to long and get on the gas smoothly when you let off the brakes to avoid driveline shock.

3. Keep a close eye on the shifting of your trans while driving normally and start checking the CV/U-Joints for wear. If you don't you may get a nasty surprise.

This can be done safely but please take a less aggressive approach to it or you are going to be buying a new transmission fairly quick.

Hope this helps.

Bryan
BryanH is offline  
Old 07-28-2000, 09:55 PM   #13
griffin
Scooby Newbie
 
Member#: 1387
Join Date: Apr 2000
Location: MN
Vehicle:
. 2007 STI Black
2001 S2000 Black

Post

Would a transmission fluid cooler help?
griffin is offline  
Old 07-28-2000, 09:56 PM   #14
BryanH
Scooby Guru
 
Member#: 993
Join Date: Feb 2000
Chapter/Region: MAIC
Location: nova
Post

Yes. But not as much as paying more attention to the maint. and technique during launching.
BryanH is offline  
Old 07-28-2000, 11:14 PM   #15
Subie Gal
GC84Ever
Super Moderator
 
Member#: 301
Join Date: Sep 1999
Chapter/Region: NWIC
Location: WA
Vehicle:
1970 FF-1 & '70 Van
02 WRX/01 RS

Question

uhhhh....

ok WHYYYYYYYYYY would u want to do this??

trust me... that crap will = boiled tranny fluid... I know....

unless.... ummm... you install a tranny cooler and switch to synthetic... but it's still NOT good for your car..
Subie Gal is offline  
Old 07-28-2000, 11:17 PM   #16
griffin
Scooby Newbie
 
Member#: 1387
Join Date: Apr 2000
Location: MN
Vehicle:
. 2007 STI Black
2001 S2000 Black

Post

Yeah you guys all scared me. I am probably never doing it again.

griffin is offline  
Old 07-28-2000, 11:50 PM   #17
BryanH
Scooby Guru
 
Member#: 993
Join Date: Feb 2000
Chapter/Region: MAIC
Location: nova
Post

I assumed he would have already switched to synth. tranny fluid if he was doing something this damaging to his car.
BryanH is offline  
Old 07-29-2000, 03:56 PM   #18
spshultz
Scooby Specialist
 
Member#: 1415
Join Date: May 2000
Location: Anytown, USA
Vehicle:
2005 OBS 3.0R
'12 SantaFe

Post

While on the subject of auto tranny's I read on SPD's website that the US version runs a 4 disk clutch pack while the overseas versions run a 6 disk pack (or something like that). Has anyone else heard that? Also, someone once told me that they thought ACT could beef up your auto tranny to handle (for the right price)HP in the range of 400 or so. I just don't think the little subie auto would handle to many hard launches.
spshultz is offline  
Old 07-29-2000, 09:22 PM   #19
98mpreziveRS
Scooby Specialist
 
Member#: 972
Join Date: Feb 2000
Post

well...i was at a drag strip...(yeah i know, wrong place for the scoob...but i had a 100 bet going, against my buddy is his NA toyota MR2 '89, he bet me that he would slaughter my in the 1/4, so i accepted, b/c i knew that i had a chance, and heck, he said if it was a total slaughter i would not have to for over the $$$. and it was a joke at first, untill we raced 2X, and then for the 3rd it was ON. well i brake torque'd it and held it at 2500, then as tree light green, WHAM i wasted his arss off the line, and i won the bet. (by about 1/2 a car...phew! ) and he is a very very quick driver, and has a manual...so moral is even though auto, this is still one dang quik scoob! and yes i have mods...nothing other than exhaust, pipes, and hose(es) and wires and plugs, and nifty oil drain plug and RALLY stickers, and yes i rally as well, thus the stikerz
98mpreziveRS is offline  
Old 07-30-2000, 01:23 PM   #20
Kevin Thomas
Street Racing Instructor
Moderator
 
Member#: 110
Join Date: Jul 1999
Location: 1997 OBS, 1996 SVX, 1988 RX
Vehicle:
1989 1989 XT6

Smile

I'll try to make this short and brief. About almost 2 months ago, I took my car to the Subaru dealership to have my tranny looked at and they said it's fine. I abuse the hell out of it.

What kind of abuse? Well, I am getting a little rep in Philly because I have been killing all of the Mustangs/Camaros that I have been up against lately. Feels great! The nail in the coffin was when I beat a 12 second Ford F150 Lightning last Saturday. The people went wild.

What does this have to do with the subject? I have been flicking the NOS juice at 1.5rpms each time. This is with a 60-70 shot of NOS. Quit worrying about your tranny so much. I have been hearing funny noises (Not really funny) from my tranny since late last year but nothing seems to be wrong, YET! You be the judge.

BTW: Get a Level10 torque converter, valve body upgrade or the whole package from them. The tranny probably would be the last thing you would have to worry about. No, I haven't done this yet because I am a fool!

[This message has been edited by Kevin Thomas (edited July 30, 2000).]
Kevin Thomas is offline  
 

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
How Bad Are Auto Sales? 10 Questions and Answers AVANTI R5 Non-Subaru News & Rumors 1 07-07-2009 05:14 PM
is this bad for the tranny asianpokerpro Transmission (AT/MT) & Driveline 3 11-08-2008 02:50 AM
Is this bad for my tranny? subaruNV Newbies & FAQs 20 03-27-2008 08:04 AM
how bad for your body is corn syrup? alacrity024 Off-Topic 21 12-03-2005 12:00 PM


All times are GMT -4. The time now is 03:33 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.