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Discussion Starter #1
So i have a 2008 WRX sedan, and i was out practicing launching today. i was doing it from about 4k rpm, and my tires would chirp and the rpms would drop to a lil over 3k when i launched.

Does this mean i am boging? And i also was wondering if 4k rpm is a good point to launch from?
 

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So i have a 2008 WRX sedan, and i was out practicing launching today. i was doing it from about 4k rpm, and my tires would chirp and the rpms would drop to a lil over 3k when i launched.

Does this mean i am boging? And i also was wondering if 4k rpm is a good point to launch from?
keep doing this and you'll need a new drivetrain.
On a FWD the tires would bust loose in this situation, AWD has alot of traction so all that power is slamming into your drivetrain and your drivetrain doesnt like it. Take it up a little and gently slip the clutch in.
 

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I got my drink and my 2 step

So i have a 2008 WRX sedan, and i was out practicing launching today. i was doing it from about 4k rpm, and my tires would chirp and the rpms would drop to a lil over 3k when i launched.

Does this mean i am boging? And i also was wondering if 4k rpm is a good point to launch from?
with a turbo car you want to launch in the following way:

you rev the engine and watch your boost gague.
when you see the boost go into positive pressure is when you want to launch. This way you are launching at boost instead of getting to boost. which is what i think you are seeing as boging.

to make this easier you can get whats called a 2 step or launch control

http://en.wikipedia.org/wiki/Launch_control_(automotive)

I have launch control and i have it set to 5800rpm. i don't have to worry about blowing my tranny or ruining my expensive clutch.
 

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So i have a 2008 WRX sedan, and i was out practicing launching today. i was doing it from about 4k rpm, and my tires would chirp and the rpms would drop to a lil over 3k when i launched.

Does this mean i am boging? And i also was wondering if 4k rpm is a good point to launch from?
well i dont know how strong the new trannys are . but for 02-03 are crap.. the newer ones are a bit better.. but still weak.. even tho i still launch my 04 tranny at 5200.. before i used to do it at 4500. i dont dump the clutch at all.. i slip it really nice.. which is the reason why im on my second clutch.. but no shockload.. and i get my tires to spin but no bogging at all, dumping at any rpm is really bad for any tranny.. so dont do it..
 

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well i dont know how strong the new trannys are . but for 02-03 are crap.. the newer ones are a bit better.. but still weak.. even tho i still launch my 04 tranny at 5200.. before i used to do it at 4500. i dont dump the clutch at all.. i slip it really nice.. which is the reason why im on my second clutch.. but no shockload.. and i get my tires to spin but no bogging at all, dumping at any rpm is really bad for any tranny.. so dont do it..
yeah man if you value your tranny don't dump with a AWD subaru
 

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I usually do a slip. I will never launch over 3.5k but that's just me. I might get it up to 4k to wake up the turbo, but i'll never just dump the clutch. Think of the amount of strain on the drivetrain doot. :rolleyes:
 

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keep doing this and you'll need a new drivetrain.
On a FWD the tires would bust loose in this situation, AWD has alot of traction so all that power is slamming into your drivetrain and your drivetrain doesnt like it. Take it up a little and gently slip the clutch in.
good point. and powershifting is bad too. i blew second gear once.. :baaa:
 

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Discussion Starter #8
i know not to dump, and i dont dump the clutch! i watched a friend of mine fcuk up his diff. from dumping it.
 

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i blew my 02 tranny the second day i got the car..2nd gear, the good thing was that i only paid 7k for my suby. so i had some cash to play with.. i decided to get a 04.. but i do baby this one a lot.. and i dont let fwd owners drive my car.. i just destroy them off the digs by cars and cars..lol.. but i've never dumped my clutch. i even slip it on 2nd a bit, a clutch is way cheaper than a new tranny only paid 160 for my act organic clutch.. instead of 1000 again for a used tranny
 

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I usually do a slip. I will never launch over 3.5k but that's just me. I might get it up to 4k to wake up the turbo, but i'll never just dump the clutch. Think of the amount of strain on the drivetrain doot. :rolleyes:
+1

That's the same thing I do if I'm going to launch. Most of the time though, I don't bother launching. My turbo is in boost way under 3k, so slipping from 3k and rising works fine for me. One blown transmission is enough. I know the 6-speed is a much beefier unit, but I just can't bring myself to do anything that would resemble dumping the clutch.
 

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+1

That's the same thing I do if I'm going to launch. Most of the time though, I don't bother launching. My turbo is in boost way under 3k, so slipping from 3k and rising works fine for me. One blown transmission is enough. I know the 6-speed is a much beefier unit, but I just can't bring myself to do anything that would resemble dumping the clutch.
Did you beef anything else up when you did the swap? It's too bad you haven't experienced all of the glory of an AWD launch that the 6 speed is capable of. I had multiple launches on my STi, and never had an issue. As long as the tire pressure is kept high enough to allow tire spin, everything works fine (in an STi).

To the OP,
It hasn't been investigated in depth yet, but the 08 WRX appears to have the legacy trans, which has shown itself to be more robust than the pre-08 WRX trans, so you shouldn't have to many issues. It sounds like you got a better clutch than what is provided with a Legacy though, is it was difficult to even chirp the tires in my LGT without the clutch slipping. I wouldn't sweat it too much just yet. Have your read the stickies on launching?
 

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Discussion Starter #13
yeah. i am pretty sure i am doing everything right, but the only question is, why do i drop to 3k rpm ?
 

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I guess I have a different outlook on launching. My STi was babied, but my '02 WRX was definitely (ab)used to it's full potential. It saw dozens of launches at the strip and many more on the street (not in town, I live in BFE, etc. etc.). I always launched at 5500 or higher...never lower. I never had one peep of a transmission issue. I launched so high to ensure wheelspin. My take is that I was letting the tires take the abuse instead of the tranny. I didn't slide my foot off of the clutch, but I did do a very quick release. I just did what worked well for me and my own logic/reasoning. To each his own.

If you think you are getting a proper launch at sub 3k rpm because you are "in boost", a true launch would definitely be an eye opener.

OP...the reason your rpms fall...when you first launch you are getting some tire slippage (the chirp), and some clutch slippage (even if you dump it). During this slippage, the engine will rev a little higher. When everything grabs it will temporarily drag the engine speed down until it pulls back up. Even when I would do a nutty launch (at close to 7k) I would see this happen. It would spin (enough for visible smoke from the stands) and stay above 6k until things grabbed pulling it down to 5k or so and resumed climbing.

I don't guess I "recommend" this type of usage, I'm just relaying my results. IMO a 3500-4000rpm clutch dump where there is no tire spin is MUCH harder on the driveline than a 7000rpm dump.

VV the subyless
 

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I have a rather laggy turbo and I punch the throttle between 6 and 7k and slip the clutch just long enough to get the car rolling (tighten up the driveline) so I don't give it that initial shock load and then quickly get out of the clutch. I found slipping the clutch too much actually caused me to wheel hop which is like a jack hammer on your driveline. If you can get your clutch to transmit enough power to your tires they will spin instead of hop or bog, however you don't just want to dump because that is a lot of shock. So slip to get the car moving for a split second then get the hell out of the clutch. Keep in mind if you don't have enough power this might not work, in which case you would most likely just bog.

Edit: Using launch control helps too. I use half throttle on it to prevent getting massive backfires on E85 :). The method above works fine, but I usually spin a lot more. The two step keeps me consistent.
 

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best thing that i could suggest is to get a chatter box that you can adjust ur rpm chatter.........for those who dont know waht it does it holds ur rpms @ a specified rpm when clutch is in when ur @ full throttle. it just holds the rpms there, til u launch...........:cool:
 
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