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Has anyone tried experimenting with launching the car at different DCCD settings? I tried with the setting on auto and launched at ~3300rpms slipping the clutch out quickly and stalled. I heard the center diff. turn on and I bogged (actually I stalled and popped the clutch back in just as I was stalling). I am guessing the best takeoffs would be with the settings on manual at 65/45 rear wheel bias with a slipping the clutch around 3500rpms. But I've never tried it. ***Correction 65/35 rear wheel*** :lol:

Anyone experimented with different teqnuiques?
 

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65/45 would be interesting. perhaps 65/35? :)
only way your gonna get the quickest launch from an STi is make sure it leaves the line at least over 4000 as thats where its making max torque. i've always launched awd no less then 6-6500.
 

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How do you adjust these settings?

Can i do that on my 02 wrx sti, european model?

Any links to how its done?
 

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I'm afraid you can't do that on a 2002 European model. The 2004 North American STi comes equipped with the DCCD (Driver-Controlled Center Differential), which allows the driver to vary the front/rear torque split from 50/50 to 35/65. It's done with a little thumb-wheel knob, but there's also an Auto mode which lets the computer do the work.

Here's a cool PDF file (see Page 5): http://vocuspr.vocus.com/vocuspr30/publish/vcsPRAsset_82_58666_{5341DDE1-E0EC-4024-9CD0-65D2B0F27407}_WRX_STi_Core_Techrev31811.pdf

Or go to the Impreza section of http://media.subaru.com.

Just one of the things we're thankful for here, that they didn't give us a lame "Americanized" version of the car like they had been for so many years... :D
 

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there is kits availble for it to be fitted to your car. i think graham goode racing (dont know the site, do a search) sells things like this along with sequensial gearboxes etc. they are based in the UK. o and it isnt a subaru item and im pretty sure i remember reading it allows 100% to rear.
 

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I had the STi at the track last night and decided to mess with the DCCD for the last run. I dialed it all the way back, rev'd to about 6k, dropped the clutch and the rear tires broke loose and the back end slid about 2.5 feet to the left then took off. Not my best time, and I think I'll leave it in auto from now on. My best run of the night was a 13.2 at 102.8mph. The car has just an invidia down pipe, no other mods last night. The track was prepped with traction compound and everything, so the tires breaking loose was not because of a slippery surface.
I didn't get a chance to see if the 'locked' setting did anything better/different.
Hopes this helps someone??
 

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I'm confused. For straight road, since the weight is contributed to the front, shouldn't we set the torque distribution to 50/50 to have more torque at the front wheels rather than the rear? Correct me if I'm wrong. :-?
 

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when i race at drag strip i switch it all to the rear as it is easier to push a car than pull(get it?) i do a good burn before ...stage and bring it to about 5200/5500 rpm and wind until i feel it start to catch and then pop it....stock my best run in n.h 13.5 100 mph. it was my first time...i've been practicing my launch and that damn third gear shift...i missed third twice out of six runs...and my mods will be done by then...look out! theres a new sheriff in town and he eats the eclipse for lunch!!!!!!!!
 

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question? are you guys racing on the Potenzas? i am curious to hear from anyone who has been running drag radials. the Potenzas don't seem to be an ideal choice for the strip. i believe NITTO is making drag radials in 17inch + sizes.
 
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Would it not be better to leave it on auto? The auto setting would adjust for maximum traction with less wheel spin which should equate to maximum acceleration and take off time. I've never tried this but just throwing around what I think.
 

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viking067 said:
How do you adjust these settings?

Can i do that on my 02 wrx sti, european model?

Any links to how its done?
Try looking for a STI Type RA Spec C model tranny. Some models come with the DCCD center diff's installed. The link below offers an upgrade kit, but not sure of the availability.

Here is a sample of what you can find....

http://www.rallispec.com/product-gearbox.htm

But I am sure that you could find a european dealer for these parts.
 

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I launch with it set in Auto. I pulled several 1.68 60' times. I didn't see any improvement varying the torque split. I can run consistant 1.7's with it in auto so I see no need to change it. I figure the computer does just fine thinking on it's own.

My $0.02

CoreySTi04
 

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Funny coincidence

CoreySTi04 said:
I launch with it set in Auto. I pulled several 1.68 60' times. I didn't see any improvement varying the torque split. I can run consistant 1.7's with it in auto so I see no need to change it. I figure the computer does just fine thinking on it's own.

My $0.02

CoreySTi04
Ditto here with AUTO. 1.68 60' time, with a 13.243 in the Quarter...Actually was slower on eevery other setting
 

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A noobie question (but trying to learn everything i can so i dont ruin anything) but whens the best time to shift for fastest acceleration in the Sti?
 
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