Welcome to the North American Subaru Impreza Owners Club Thursday March 28, 2024
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC General > General Community

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.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 11-18-2012, 01:44 AM   #1
Subiezilla
Scooby Newbie
 
Member#: 280543
Join Date: Apr 2011
Default How to "launch" car non drag/racing

Fist off I have read ubabombers manifesto in shifting, and the launching section of it seems only apply to racing applications. What I want to know is how to "launch" our wrx's for daily tasks like making a left turn from a yield stop with oncoming traffic, or say merging onto freeway from the traffic control light. Something in which I want to get going relatively fast but not break neck speed of drag racing. I would like not to have the engine bog down when I let out the clutch.

Thanks
Subiezilla is offline   Reply With Quote
Old 11-18-2012, 01:51 AM   #2
kh15
Scooby Specialist
 
Member#: 132400
Join Date: Nov 2006
Location: New Orleans
Vehicle:
2006 WRX

Default

you always let the clutch out the same, that never changes. In certain situations you just get on the gas a bit more.




kh15 is offline   Reply With Quote
Old 11-18-2012, 01:56 AM   #3
iAmjudge
Scooby Newbie
 
Member#: 300236
Join Date: Nov 2011
Chapter/Region: MWSOC
Location: Elmhurst IL
Vehicle:
2011 WRX
Silver

Default

How long have you been driving a manual car? It becomes second nature sooner or later, I honestly don't remember the last time I looked at my RPM's when starting off, but you don't technically launch the car when trying to turn, or get going in everyday driving.
iAmjudge is offline   Reply With Quote
Old 11-18-2012, 02:05 AM   #4
Subiezilla
Scooby Newbie
 
Member#: 280543
Join Date: Apr 2011
Default

Quote:
Originally Posted by iAmjudge
How long have you been driving a manual car? It becomes second nature sooner or later, I honestly don't remember the last time I looked at my RPM's when starting off, but you don't technically launch the car when trying to turn, or get going in everyday driving.
For 3 years. But I always would just drive normally until my buddy this weekend pointed out that at a ~3,000 rpm rev "launch" at the freeway entrance my car bogged a little bit. I have pretty much never tried lauching or used the lauch control feature on my AP because iv been afraid of what could happen to my tranny. So mainly I always drive normally take off at 1k to 1,500 rpm. This i just something i never masters or attempted to master even over all these years ***128531;
Subiezilla is offline   Reply With Quote
Old 11-18-2012, 02:08 AM   #5
iAmjudge
Scooby Newbie
 
Member#: 300236
Join Date: Nov 2011
Chapter/Region: MWSOC
Location: Elmhurst IL
Vehicle:
2011 WRX
Silver

Default

I'm probably at 1500 - 1600 when I need to get going quickly and my car doesn't bog at all...

Maybe your letting the clutch out too quickly?
iAmjudge is offline   Reply With Quote
Old 11-18-2012, 02:18 AM   #6
Subiezilla
Scooby Newbie
 
Member#: 280543
Join Date: Apr 2011
Default

Quote:
Originally Posted by iAmjudge
I'm probably at 1500 - 1600 when I need to get going quickly and my car doesn't bog at all...

Maybe your letting the clutch out too quickly?
I'm fine with 1500 rpm starts its the 3k one I tried that I failed at. But I will try letting the clutch out slower I guess, but wouldn't letting it out slower also wear out the clutch more?

Edit: I know that it's better to ride the clutch vs grenade your tranny....but again i see this tip for propel that are revving to 5k + rpm's and drag racing. I'm only doing 3k rpm if at that
Subiezilla is offline   Reply With Quote
Old 11-18-2012, 02:29 AM   #7
tibug
Scooby Specialist
 
Member#: 273906
Join Date: Feb 2011
Chapter/Region: NESIC
Location: U.S. (Рос
Vehicle:
2005 Lexus
Grandpa

Default

Quote:
Originally Posted by Subiezilla View Post
I'm fine with 1500 rpm starts its the 3k one I tried that I failed at. But I will try letting the clutch out slower I guess, but wouldn't letting it out slower also wear out the clutch more?
Yea it will, but in my experience, it takes just a little more of a pause at the catch point to be able to let the clutch out without bogging. Just a little hesitation and you're good. You just have to get the feel for it so that you don't keep the clutch at the catch point longer than you need to.

There's really no other solution to it; in order to keep the car from bogging down, your speed needs to match the RPMs of the engine when you engage (let off) the clutch, and in order for that to happen, you HAVE to slip the clutch. If you want to start at 3k RPMs, you've got to slip the clutch more than if you want to start at 1500 RPMs.
tibug is offline   Reply With Quote
Old 11-18-2012, 02:36 AM   #8
Subiezilla
Scooby Newbie
 
Member#: 280543
Join Date: Apr 2011
Default

Quote:
Originally Posted by tibug

Yea it will, but in my experience, it takes just a little more of a pause at the catch point to be able to let the clutch out without bogging. Just a little hesitation and you're good. You just have to get the feel for it so that you don't keep the clutch at the catch point longer than you need to.

There's really no other solution to it; in order to keep the car from bogging down, your speed needs to match the RPMs of the engine when you engage (let off) the clutch, and in order for that to happen, you HAVE to slip the clutch. If you want to start at 3k RPMs, you've got to slip the clutch more than if you want to start at 1500 RPMs.
Thanks will try it and report back
Subiezilla is offline   Reply With Quote
Old 11-18-2012, 02:10 AM   #9
Thunderpaw
Scooby Specialist
 
Member#: 242205
Join Date: Mar 2010
Location: Dallas
Vehicle:
2009 I don't know
Dirt

Default

Launch your car, just do it ::nikead::
Thunderpaw is offline   Reply With Quote
Old 11-18-2012, 02:42 AM   #10
ResidentR
Scooby Specialist
 
Member#: 281656
Join Date: May 2011
Chapter/Region: MAIC
Location: Centreville, VA
Vehicle:
2011 DGM WRX
5dr limited

Default

This is gonna smell real good.

Launching these cars is hard.
ResidentR is offline   Reply With Quote
Old 11-18-2012, 04:43 AM   #11
grknss
Scooby Specialist
 
Member#: 44592
Join Date: Oct 2003
Chapter/Region: South East
Location: Red Banks, MS
Vehicle:
2004 WRX STI
Platinum Silver Metallic

Default

Quote:
Originally Posted by ResidentR View Post
This is gonna smell real good.

Launching these cars is hard.
^^^^^^ +1
grknss is offline   Reply With Quote
Old 11-18-2012, 11:15 AM   #12
Subiezilla
Scooby Newbie
 
Member#: 280543
Join Date: Apr 2011
Default

Quote:
Originally Posted by ResidentR
This is gonna smell real good.

Launching these cars is hard.
Yeah this is what I'm afraid off
Subiezilla is offline   Reply With Quote
Old 11-18-2012, 11:23 AM   #13
snake32
Scooby Specialist
 
Member#: 167338
Join Date: Dec 2007
Chapter/Region: TXIC
Location: Texas
Vehicle:
11 Wrx hatch
Dgm

Default

have you ever seen that video on youtube of this guy launching his rex at redline to beat a vette? message him on youtube for some mad advice, lol
snake32 is offline   Reply With Quote
Old 11-18-2012, 11:45 AM   #14
mrkyle3
Scooby Specialist
 
Member#: 272675
Join Date: Feb 2011
Chapter/Region: NESIC
Location: West Haven, CT
Vehicle:
2011 WRX
2002 Corvette Z06

Default

Just slip the clutch to prevent bogging. Also protects your tranny. A clutch is waaaaaaay cheaper than a new transmission.

I've 'launched' once or twice only when it was necessary in traffic. For example, I didn't realize I had to be in the left lane for my exit and traffic was stopped except for the exit lane. Cars in exit lane going ~60-65, my lane going 0 mph. Rev'd to around 4k then let clutch out to engagement point and slipped it until the car was moving. You will smell clutch burning, but that is normal considering what you are doing.

Last edited by mrkyle3; 11-18-2012 at 11:50 AM.
mrkyle3 is offline   Reply With Quote
Old 11-18-2012, 11:54 AM   #15
Back Road Runner
Scooby Guru
 
Member#: 60082
Join Date: Apr 2004
Chapter/Region: MWSOC
Location: Minnesota
Vehicle:
2004 Forester STI
Silver

Default

These cars, even 300whp ones, will not break tire traction before the engine runs out of power. I'm at 21psi, on winter tires, and I can not spin my tires short of a rain soaked road with a redline launch in my very low 6sp first gear. The 5sp has a much taller 1st, so they are even harder to break traction at the same engine power. Yes, you can spin tires if you shock load the drivetrain. A 2.5L NA will do that too, will also chirp in 2nd gear if you want to. I'm only duscussing actual, smooth delivery of power.

It takes a LOT of torque and gearing to break 4 tires free without shocking the drivetrain.

Because we are engine limited in this equation, we need to slip the clutch to allow the engine to keep up in revs. This also means a strong launch is a high rpm launch. The car makes the most power at or very near redline, so you launch at or near redline. You will not spin tires unless traction is pretty low or you are not smooth with your power delivery. The higher the revs you go, the more power the engine can produce for accelerating the car. Because the engine is limiting, it also means you can use full throttle. The variable will then become only the clutch. You simply slip that as much as needed to keep the revs high and the engine making power. The car will accelerate quite briskly.

Maybe you guys will start a flame war on the wrongs of redline launching and that it's magically bad for the car. Yes, it will wear the clutch more. A clutch is no different than brakes. The flywheels is the same as a brake rotor, and the clutch disk is your brake pad. They aren't really different at all in compound either, often an organic type just like many oem pads. It's also why you can glaze a clutch just like an organic brake pad if you overheat them. The ability to overheat a clutch takes a little bit of effort, more specifically many launches in a short time frame. Longevity depends on how much you do, just like brake pads. It's a wear item.

So how long is longevity with launching? Not bad really. I own a 02 Forester NA that I auto-x and rally-x. It's seen 5 years of use and every run starts with me launching the car at redline. I figured it has somewhere near 250 redline launches on the stock clutch, and this is car with 120k+ daily miles to boot. My bro's FXT had a couple years of auto-x and rally-x use before an engine rebuild. The car was again launched are redline religiously at events. A new clutch went in at 75k miles when the engine was rebuilt after a #4 piston failure. The clutch still had half its life left. The car now runs an Exedgy clutch again, just one step up, and again has years of use added up plus all daily use. Mind you this is with a "fragile" 5sp running 21psi with an 18G. It's been at 21psi most of its ownership. I have a FXT now too, this time with a 6sp, and again I launch at redline at events.

So what's wrong with launching your car? Most often it's only a problem when people shock load their drivetrain or attempt to launch repeatedly with very short intervals of time in between. I personally haven't seem a problem with launches as short as 1.5 minute intervals and repeated a half dozen or more times in a row.

Higher power cars will cause more heat. It's always good to feel for any changes in engagement behavior that may indicate an excess in heat build up. If so, let the car sit a little. Organic material isn't exactly great with heat, although the clutch and flywheel are pretty well sized and can hold and move a good deal of heat around quickly. Still, it's just like your brakes. They can overheat, they will wear, and you can abuse them.
Back Road Runner is offline   Reply With Quote
Old 12-08-2012, 08:19 PM   #16
MtnXfreeride
Scooby Specialist
 
Member#: 228010
Join Date: Oct 2009
Chapter/Region: NESIC
Location: Maine
Vehicle:
2019 WRX Limited
Crystal White Pearl

Default

Quote:
Originally Posted by Back Road Runner View Post
These cars, even 300whp ones, will not break tire traction before the engine runs out of power. I'm at 21psi, on winter tires, and I can not spin my tires short of a rain soaked road with a redline launch in my very low 6sp first gear. The 5sp has a much taller 1st, so they are even harder to break traction at the same engine power.
What? I can break traction no problem in my WRX, stage 1 with cobb intake on all seasons on dry pavement at ~40F pavement.


I have the same problem as OP, Ive only been driving stick for 6 months and according to my brother his 0-15mph is faster in his automatic mazda 3.

Basically if Im not doing an all out launch at 3.7K and burn my tires on launch then I bog it and have a slower than non-launch start. I will try slipping the clutch more at that grabbing point.
MtnXfreeride is offline   Reply With Quote
Old 12-08-2012, 08:29 PM   #17
JJL91
Scooby Newbie
 
Member#: 320380
Join Date: May 2012
Location: Buffalo NY
Vehicle:
2012 wrx
rally blue

Default

Quote:
Originally Posted by MtnXfreeride View Post

What? I can break traction no problem in my WRX, stage 1 with cobb intake on all seasons on dry pavement at ~40F pavement.

I have the same problem as OP, Ive only been driving stick for 6 months and according to my brother his 0-15mph is faster in his automatic mazda 3.

Basically if Im not doing an all out launch at 3.7K and burn my tires on launch then I bog it and have a slower than non-launch start. I will try slipping the clutch more at that grabbing point.

I find it hard to believe you "burn your tires" at a 3.7k launch.
JJL91 is offline   Reply With Quote
Old 12-09-2012, 12:15 AM   #18
NCORWRX
Scooby Specialist
 
Member#: 238919
Join Date: Feb 2010
Chapter/Region: NWIC
Location: Back in the Rogue Valley baby!
Vehicle:
007 LGT LTD
DGM stg1

Default

Quote:
Originally Posted by Back Road Runner View Post
I figured it has somewhere near 250 redline launches on the stock clutch
^^^^That is truly unbelievable... Great info otherwise, but I have a damn hard time with that statement.

Last edited by NCORWRX; 12-09-2012 at 03:25 AM. Reason: just cause... nevermind.
NCORWRX is offline   Reply With Quote
Old 11-18-2012, 12:16 PM   #19
TrakJunky
Scooby Newbie
 
Member#: 300501
Join Date: Nov 2011
Chapter/Region: NWIC
Location: NORCAL STICKS
Vehicle:
09 Heated seats!
SWP

Default

My question is, if you didn't notice it before, what's the big deal now? And why are you letting your buddy, who doesn't drive your car every day, get in your head with rediculous sentiment. Obviously nothing is wrong with your car. And the way you get around in traffic.

If you launch your car at higher RPM's it's going to wear stuff out faster. No way gettig around it. Just keep doing what you are doing and you will be fine.

And if you are Coming off at 3k, your revs will drop And you will not be in the boost until it they come back up, your buddy doesn't seam to get what turbo lag is.
TrakJunky is offline   Reply With Quote
Old 11-18-2012, 12:29 PM   #20
m1r4g3
Scooby Specialist
 
Member#: 220476
Join Date: Aug 2009
Chapter/Region: South East
Location: Jacksonville
Vehicle:
2--> 06 STI & 12 Leg
WRB & SWP

Default

im confuzed by this thread. launching a car but not for racing? its all about clutch disengagement vs throttle position.
m1r4g3 is offline   Reply With Quote
Old 11-18-2012, 12:35 PM   #21
Back Road Runner
Scooby Guru
 
Member#: 60082
Join Date: Apr 2004
Chapter/Region: MWSOC
Location: Minnesota
Vehicle:
2004 Forester STI
Silver

Default

Yeah, there's nothing special here, just car nerds discussing car nerd stuff for fun.

I think his concern was trying to accelerate more quickly without bogging the car. People by nature want to use the clutch as little as possible, so they will want to get off of it too quickly and subsequently bog the engine. Unless you have gobs of torque, low grip, or shock load the drivetrain enough to break the tires free, the engine will always bog. The only way around this is to use the clutch more, slip longer, and let the engine hold revs. There's nothing fancy here, but we start doing what people have been taught to fear doing.
Back Road Runner is offline   Reply With Quote
Old 11-18-2012, 12:52 PM   #22
Subiezilla
Scooby Newbie
 
Member#: 280543
Join Date: Apr 2011
Default

Quote:
Originally Posted by Back Road Runner
Yeah, there's nothing special here, just car nerds discussing car nerd stuff for fun.

I think his concern was trying to accelerate more quickly without bogging the car. People by nature want to use the clutch as little as possible, so they will want to get off of it too quickly and subsequently bog the engine. Unless you have gobs of torque, low grip, or shock load the drivetrain enough to break the tires free, the engine will always bog. The only way around this is to use the clutch more, slip longer, and let the engine hold revs. There's nothing fancy here, but we start doing what people have been taught to fear doing.
Yes u are correct, by nature we have been taught not to ride the clutch at least thats how my dad taught me but that was when he taught me in a 92 Nissan Hard Body pick up though. Obviously my subie is a totally different beast with awd. But I guess the other poster is right iv been fine with my car since I bought it back in 09 so I won't try to worry so much and I don't drag race so it's all good.
Subiezilla is offline   Reply With Quote
Old 11-18-2012, 01:01 PM   #23
kj15991
Scooby Newbie
 
Member#: 293548
Join Date: Sep 2011
Chapter/Region: NWIC
Vehicle:
2005 wrx sti
aspen white

Default

just rev it to 5k and drop the clutch -___-
kj15991 is offline   Reply With Quote
Old 11-18-2012, 01:10 PM   #24
H_wells3000
Scooby Specialist
 
Member#: 322035
Join Date: Jun 2012
Chapter/Region: BAIC
Default

Quote:
Originally Posted by kj15991 View Post
just rev it to 5k and drop the clutch -___-
and BOG, listen to the Guru
H_wells3000 is offline   Reply With Quote
Old 11-18-2012, 01:29 PM   #25
mrkyle3
Scooby Specialist
 
Member#: 272675
Join Date: Feb 2011
Chapter/Region: NESIC
Location: West Haven, CT
Vehicle:
2011 WRX
2002 Corvette Z06

Default

Quote:
Originally Posted by kj15991
just rev it to 5k and drop the clutch -___-
He asked how to launch not rip the teeth off first.
mrkyle3 is offline   Reply With Quote
Reply

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 Off
Forum Jump

All times are GMT -4. The time now is 11:38 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.

When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission
Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.