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-   -   New Launch technique! (http://www.wrxtuners.com/forums/f113/new-launch-technique-23995/)

BC_Girl 08-16-2008 10:54 AM

New Launch technique!
 
So, went to the track again on Wednesday. Air quality was great, not too humid, and just cool enough. 1st run was a 15.4, pretty good for my first run compared to previous 1st runs. Then I lined up next to this guy in a nissan (unsure what, it was heavily modded and debaged). He told me to try launching at around 3000 rpms instead of the 5000 rpms I was previously launching at. I tried it and I was surprised....it worked. I didn't have to slip the clutch as much, it didn't buck, it was one of those throw your head back and leave you smiling from ear to ear for the entire run kind of launches. :rocks: I also had my best 60ft time ever ( 2.1) Yeah, I know, that's still unacceptable, but I just can't seem to get it below 2. :pity: I kept it WOT between shifts ( with the exception of shifting from 1st to 2nd). I ran a 15.07. My best is 15.02. I have a feeling that if I had done more runs I would have broke 15, but they were packed and I only got 3 runs. ( Don't even want to talk about the 3rd run...it was a waste of gas and time. ) Anyways, my conclusion is.....enough of this shit it's time for my exhaust system.

shamrock 08-18-2008 08:14 AM

[QUOTE=BC_Girl;202769]So, went to the track again on Wednesday. Air quality was great, not too humid, and just cool enough. 1st run was a 15.4, pretty good for my first run compared to previous 1st runs. Then I lined up next to this guy in a nissan (unsure what, it was heavily modded and debaged). He told me to try launching at around 3000 rpms instead of the 5000 rpms I was previously launching at. I tried it and I was surprised....it worked. I didn't have to slip the clutch as much, it didn't buck, it was one of those throw your head back and leave you smiling from ear to ear for the entire run kind of launches. :rocks: I also had my best 60ft time ever ( 2.1) Yeah, I know, that's still unacceptable, but I just can't seem to get it below 2. :pity: I kept it WOT between shifts ( with the exception of shifting from 1st to 2nd). I ran a 15.07. My best is 15.02. I have a feeling that if I had done more runs I would have broke 15, but they were packed and I only got 3 runs. ( Don't even want to talk about the 3rd run...it was a waste of gas and time. ) Anyways, [B]my conclusion is.....enough of this shit it's time for my exhaust system[/B].[/QUOTE]

:nono: This will not end very well for your transmission. Stockish WRX drivetrains are not meant for the drag strip. And you know that you need some type of tune/EM before you throw a TBE on, right

christommy 08-18-2008 01:17 PM

not trying to thread jack but one of my buddies from a lil car group here in town told me to try using the e-brake, like set the e-brake, then get the clutch to the friction point all while revving at desired launch rpm, and then just releasing the e-brake.

now i know this is very bad for the clutch but has anyone tried this with success??

SuBeast 08-18-2008 04:37 PM

[QUOTE=christommy;202849]not trying to thread jack but one of my buddies from a lil car group here in town told me to try using the e-brake, like set the e-brake, then get the clutch to the friction point all while revving at desired launch rpm, and then just releasing the e-brake.

now i know this is very bad for the clutch but has anyone tried this with success??[/QUOTE]

I dont know if my reply will be very usefull, since I have never even tried it with a WRX, but it has worked for me and my brother and other friends in our FWD cars. it works really well with other cars, but i'm not sure about the wrx.

mosc 08-18-2008 05:40 PM

What you've suggested will give you a nice jolt from the line. It will also bog the motor horribly. Congrats, you've just invented a way to put much more wear on the car while going slower.

I know I'm being a jerk and all but you're not the first person to drag race a manual transmission. There are decades of experience out there that you're spitting in the face of. Try mastering the RIGHT way before coming up with a NEW way.

christommy 08-19-2008 03:23 AM

[QUOTE=mosc;202865]What you've suggested will give you a nice jolt from the line. It will also bog the motor horribly. Congrats, you've just invented a way to put much more wear on the car while going slower.

I know I'm being a jerk and all but you're not the first person to drag race a manual transmission. There are decades of experience out there that you're spitting in the face of. Try mastering the RIGHT way before coming up with a NEW way.[/QUOTE]

naw its ok, i was just asking if anyone has tried this before and for peoples opinion on this kind of launch, i myself have never tried to launch this way. i knew it is bad but wanted to see what peoples thoughts were about it.

and i know im not the first thats why im asking around trying to figure out what the best way to launch is. :)

mosc 08-19-2008 03:24 AM

it's deceiving because you will get a serious jolt. This will immediately be followed by a bogged down motor that has to spend more time getting back up in RPMs. Thus it's slower. Again, it's awful for the car as well.

christommy 08-19-2008 03:30 AM

[QUOTE=mosc;202889]it's deceiving because you will get a serious jolt. This will immediately be followed by a bogged down motor that has to spend more time getting back up in RPMs. Thus it's slower. Again, it's awful for the car as well.[/QUOTE]

alright, good to know to not ever do that launch technique, thanks for the info !Thumbs Up

SuBeast 08-19-2008 04:38 PM

I saw this guy with a silver bugeye do that launch, he didn't use the e-brake though, but it jolted out in front of a Stage2 Roush Mustang probably about 2 car lengths off the line and then finally got passed in the wrx's 4th gear... But I heard it bog down after the launch, it was still pulling on lower speeds, but I heard it bog and then slowly rev up...

ProZach626 08-19-2008 09:24 PM

What are the WRX's supposed to run in the 1/4 stock? 15's seems slow for a WRX, considering my spec v can hit mid 14's. This is discouraging me from buying a rex. :(

turmic 08-19-2008 11:05 PM

That is completly stock as BC_Girl has stated. Is your Spec V stock?

You have to consider this first. WRXs and STIs are not built to be drag machines. They have a rally heritage in their background and also make great autocross/track/time attack cars. Though, I've been hearing that evos are slightly better at time attack. That's neither here nor there. AWD has a higher power loss to the wheels from the added drive train. With all that being said...a majority of the time when launched properly. A AWD car will out launch a FWD or RWD car because of the ability to put the power down to all four corners. The wheel power loss hits later in the run normally. Meaning that sometimes the opposition will start to catch you at the end of the run.

Totally off topic by this point. If your spec v isn't stock, then your comparing apples to oranges. Plus, the 2.5L 06+ wrxs have some more torque thanks to the displacement boost. I believe, someone correct me if i'm wrong. They have a slightly quicker 1/4 mile time. I don't have the facts or numbers on me at the time.

mosc 08-20-2008 10:56 AM

stock for stock, the 06+ runs 2psi less boost and had a 500rpm shorter powerband along with the same max hp so those make up for the added torque down low and the cars come out virtually the same. A stage 2 06+ though will be running the same boost as a stage 2 02-05 so it does show a bit faster.

BC_Girl 08-21-2008 03:53 AM

[QUOTE=shamrock;202840]:nono: This will not end very well for your transmission. Stockish WRX drivetrains are not meant for the drag strip. And you know that you need some type of tune/EM before you throw a TBE on, right[/QUOTE]

EM BEFORE an exhaust? I've never heard that before. I know after install that I need some EM. Isn't it harder on the tranny to launch at higher RPMs? Wouldn't a 3000 rpm launch be safer than a 5000rpm launch? It's tough on the tranny no matter what, but is one better than the other? My WRX is stock, not pushing a lot of power to the drive train I mean....I don't claim to be an expert, but it seems that this conflicts with the info I've recieved on here in the past.

shamrock 08-21-2008 10:00 AM

[QUOTE=BC_Girl;203008]EM BEFORE an exhaust? I've never heard that before. I know after install that I need some EM. Isn't it harder on the tranny to launch at higher RPMs? Wouldn't a 3000 rpm launch be safer than a 5000rpm launch? It's tough on the tranny no matter what, but is one better than the other? My WRX is stock, not pushing a lot of power to the drive train I mean....I don't claim to be an expert, but it seems that this conflicts with the info I've recieved on here in the past.[/QUOTE]


Yes, I said that wrong, let me put it this way. The day you do a TBE, you need to use some type of EM. The 04-05 ECU is not like the bug eyes. 02-03 could be ok without any em. But we need it. I would not launch the the WRX without a 6-speed swap/ppg gear box. Yes you may get away with it a few times(launching), but one day it will catch up to you!Cry!

mosc 08-21-2008 11:34 AM

[QUOTE=shamrock;203017]Yes, I said that wrong, let me put it this way. The day you do a TBE, you need to use some type of EM. The 04-05 ECU is not like the bug eyes. 02-03 could be ok without any em. But we need it. I would not launch the the WRX without a 6-speed swap/ppg gear box. Yes you may get away with it a few times(launching), but one day it will catch up to you!Cry![/QUOTE]
I disagree completely. The 02-03 and the 04-05 ECU are virtually identical. They both respond very well to a downpipe with or without EM. The years where the downpipe and no EM is a problem is 06+ and that's got nothing to do with the ECU, it has to do with the 2.5L flowing too much for the stock wastegate settings after the mod.

I've seen you post like this before and it's just wrong. The body style change from 03 to 04 was the major difference between those two cars. The tranny actually changed PRIOR to the 04 (midyear 03) and even that was only a small change. The ECUs, and most everything else, are practically identical.

As for your advice requiring a 6-speed to launch, I think that's absurd. The 6-speed ain't indestructible either you know.

BCgirl, what breaks trannys is shock loading. This is the jolt of torque when the clutch first engages. The more torque it has to adjust to, the more likely it is to snap over time. You can reduce shock loading by a) not launching and just going slower (I know, not what you want) and b) being as smooth as possible as you release the clutch from a pre-spun RPM. It's easier to be smooth the lower the RPM so in some sense yes, it is easier on the tranny to launch from 3k than 5k.


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