Q's about the tech of launch- ATTESA & mitsu S-AWC
 

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

Posted this here b/c 350Z and G35 don't have launch but GTR does so I thought maybe it was the appropriate forum.

So I'm trying to to figure out what feedback launch controls in AWD vehicles use to determine how much power to put to the wheels.

I was looking at ATTESA on wiki and it says "Unlike the previous ATTESA systems which relied heavily on mechanical feedback, the system in the GT-R uses electronic sensors and hydraulically-actuated clutches. It also has a yaw-rate feedback control system, effectively managing slip angle. Front rear torque split can go from 2:98 during a standing start to a maximum of 50:50"

I couldn't really figure out how it works during the launch. At the launch I'm wondering how much feedback from the road the GTR computers are relying on to determine how much juice to give the wheels. The reason I'm asking is because I'm wondering if I buy a used GTR in the distant future and switch up the tires to something stickier (ie ET Street) if more power goes to the wheels during launch b/c ATTESA senses less slippage or if it's all just preprogrammed levels of boost at different RPMs etc with little feedback from the actual wheelspin. This would also be good to know if you try to launch on a damp road. Or say if you launch a modded GTR with 600 hp if it will still start as well from a dig or if it will spin it's tires more b/c of the added power.

On the same subject, a more plausible car i've considered is a cheaper used car in maybe 4 years, an Evo X MR with the TC-SST transmission which also utilizes an AWD launch with S-AWC with torque vectoring. I know the S-AWC has gravel/tarmac/snow options which makes me think it's kind of asking the driver to help the car figure itself out by selecting one of the 3 different programs and not sensing the slippage through road feedback very confidently itself... So any comments on the mitsu technology is appreciated too since i wont be assuming all launch programs are equal...i can't seem to find these details in the brochures...

Technically there is no launch control in a GT-R.........it's to get you unstuck from snow/sand. lolz.

Anyhow I don't know if I've ever read of anyone asking that question. I'd post that question on NAGTROC instead of here.

nah you guys are pretty smart, I lurk. And hey, you responded!

Though I know you know that I know that you know that it's just semantics regarding the launch control, just if i included disclaimers of that nature in all of my posts they'd be reallllly long.

I can tell you the wheels will spin just like any other car when launching a 600hp GTR. To answer you other question well I'd wait for another person with more experience to answer. In the meantime Drag-Time.info had a long video of a Switzer P800 GTR launching on the street multiple times up hill and downhill spinning the tires on the launch. Search for that video on youtube.

are you looking to drag race this car or just to use it on Honda civics at stoplights?

This is apart of the mystique of the car, you first need someone to de-code the software, then someone the who can understand the mechanical bits, and lastly someone who can merge the two together.

so basically no one knows?