So I've never launched my WRX and am thinking about going to Commerce friday with a couple of friends and seeing what kinda times I can pull. How do you guys launch your cars? I've heard rev up to 4500 and then slip the clutch however much 'feels' right. If any of the locals wanna help me out I'm pretty free all week if anybody knows a good practice spot.
I slip the clutch at 5k or so. Just 'blip' the throttle a bit, then push down firmly while you smoothly let the clutch go.
I still suck at launching, but so far I have just dropped the clutch, not bogging it from 4k to 5.5k and broke a tranny doing that 27+ times. These kind of launches seem to pull stronger. I have tried to slip the clutch a few times but the pulls were weak and I still have not tried many times with this technique. To me it's either: Replacing a tranny, or replacing a clutch. So If I ever go dragging again(which should be never), it'll be more burning than dumping.
1. keep revs between 5000-5500 rpm to keep the car out of much vaccum as possible (does similar to what a launch control does to my understanding) watch your boost gauge on few tries 2. let out the clutch quickly, someone said on IWSTI that imagine you stepped into dog poo and you took your foot out of that, roughly the rate you should let out the clutch. 3.I also learned to not pivot your foot with the ankle on the floor, but lift your entire foot. 4. Do not dump/side step off the clutch, let it off quickly, do not pause at the engagement point or you will smell your clutch. If you smell your burnt clutch or bogged the launch, it means you are too slow on letting the clutch out. 5. I learned that a perfect launch should not bog at all, zero burning of the clutch and a tiny hint of wheel spin and off you go. 6. Oh and hold on to your life and be ready to grab second note: if you are afraid of breaking something, do not launch at all
my launches in my WRX were good for 1.8 60 foot times... not necessarily great but the transmission lasted... 1) stomp the gas 2) when the rpm passes 4500, i start letting go of the clutch, taking about 1 second to get off it completely in a linear fashion i noticed that the timing was just right if i stomped the gas after the first light fell and started letting off the clutch just before the green light came on... if u rev higher, u could let the clutch off quicker without falling out of boost
Heh i like the dog poo thing. I'd never thought about it this way but thats pretty much what i do... I launch between 4k-5k. I usually do more dumping than slipping but it is not a complete dump. Its a smooth quick dump. You wana get the wheels spinning quickly right away to ease the strain on the drive train but then have the rpm's down low enough to where the car catches up with the wheels quickly too. I'm gonna have to play with my launches now since i just went from bald tires to reallly sticky 255's .
I rev it up high and slowly slip it....by the time I have the clutch all the way out in 1st it is time to shift to 2nd it seems. My problem is I have a bad baulk ring in my tranny so 1st to second it tricky. Drag racing is not in my future till I rebuild the transmission.
isnt reving up and dumping the clutch a bad thing? wont you tear your clutch or snap an axle or something?
Yeah that is why you don't dump it, but ease into it or release smooth and steady. You still run the risk of breaking stuff....that is just part of launching, but you minimize it.
launching is a blast in the RS, 2800 lbs and a 4.44 rear end makes things a lot less stressing on the drive line.
I was talking to the guy who runs his STi for national SCCA Pro Solo events, and puts down 1.6 60ft times, and here is what he does: -- Brian
BTW: our clutch is finally starting to go out, after 150+ clutch dumps over the last 2 years, and 34k miles on the car. This is quite good, compared to stories that I have heard from evo people. The clutch is still holding on launching and lower gears, but is starting to slip in 5th and 6th on the highway a bit. Luckily, a new clutch disc, pressure plate and pilot bearing are $231.43 from subarugenuineparts.com (~27% off the MSRP price that SOG and most dealers charge). Prestige Subaru takes 20% off MSRP also. We will try to reuse the release bearing, but if it is worn, that is another $100.58. I can take some pics of the clutch replacement if you guys are interested. -- Brian
With revving that high and dumping the clutch I wouldn't be worried about the clutch, I'd be worried about my transmission. When you dump the clutch like that in an awd drive car, the transmission takes the brunt of the force. I know you can get a little wheel spin (definitely during rain), but I don't think you can get enough to offset the strain put on the tranny. That's my understanding of it at least.
If you dump the clutch high enough, you will get all 4 wheels to spin. I wouldn't do this on the wrx, but don't see issues with the STi. -- Brian
Doesn't the wrx/sti have a limited slip of sorts that fights all wheels going tractionless, I'm not saying they won't, but it seems like the car would be fighting it. And regardless, GTScoob you have a wrx, don't do this :hsnono:
I was not aware of that. Well that will probably make it less of a problem because it's stronger. But it's really more of a power issue as far as strain on the transmission. I mean his will hold up better, but it's still getting the same spinning backfist everytime it's launched. It will just take more of them to knock it out. (you like that Shone Carter UFC reference? yeah you do.)
At Silver Dollar I always roll through the water box. It helps get a little wheel spin. At Commerce they get mad if you drive through it and don't do a burn out. I think this wheel spin and an organic clutch helped my tranny survive 400+ ftlbs of torque. My 60's at Silver Dollar are usually low 1.7's and an occasional 1.6 at Commerce it's low to mid 1.7s. It's either driving through the water box or 60ft in Commerce is different than 60ft at Silver Dollar.
Sorry guys I didn't even see this thread. The trick is to get ALL the slack out of the tranny and the engine. I do sorta like a standing brake stand. I get to the tree and only let one light come on. I think take my left foot and clutch in and press the brakes. While releasing the clutch I wait until I feel the car start moving and press down on the brakes while lightly pressing the gas to keep the car alive. Your car will feel like it's sluggish and all but the boost will start to come up and you take all the slack outta the driveline. When the second light is on the car should be around 4K rpms (ya better have some good brakes for this and a good clutch). Every track I've been to has 3 lights that stage down the third being the green go light. Well you are sitting at 4-4.5K rpms and when you see that second light don't hesitate and slam the gas down and let go of the brakes and clutch. Voila your boost is instantly there and you slack is outta the driveline and you are gone gone gone. I'm always fishtailing outta first and chirping second. Also on my car I was always darn near 19 psi in 1st! (I dunno how but the quick look at the boost gauge shows me first). I also shift between 6500 if I can so my peak torque will be reached.
It never done that until after my meth injection tune. Before it never got past 12 psi in 1st but I never did this launch technique until after my meth tune.
Thanks Delette!! I knew you had some good info on staging. I'll have to try it next time I'm at the strip and see if I'm talented enough to actually pull that off. Probably not though
It's very tough and you have to 'feel' the car if you know what I mean. Also you have to have a clutch that can bite....I have a cerametallic 6 puck on mine. Also I will take this opportunity to put up a disclaimer....I take no responsibility whatsoever if anyone uses my technique. If you break then sorry!
I know this has been posted before, but just a reminder what can happen when you dump the clutch too often (even in an sti): http://www.youtube.com/watch?v=I8kebmrJfZM Here's the full video composed of many great launches and then ending with the previous video: http://www.youtube.com/watch?v=dI9WdTS10C8
Scott Sanders told me a great way to launch the car. rev to about 3500 or so and slip the clutch. This is the way he ran a 12.4 in an sti with TBE, ecutek, and big intercool.
That's more the approach that I usually go. I'm just very hit or miss on it. Sometimes I nail it, other times I bog down. But It's not something I practice very often (nor do I plan to).