S100 Launch and Traction slip %

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Rob Stevens
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Joined: Thu Jul 28, 2011 4:10 am
ECU Model: S100 Pro
Distributor: None-Coil On Plug :)

Re: S100 Launch and Traction slip %

Post by Rob Stevens »

Yes low rpm and a bit of clutch slip, logging and reviewing, I started turning the start line rpm down by hand once moving, this helped get on the traction phase sooner, try very low slip 5% but do log to check that is what you are getting
John Loudon
Posts: 18
Joined: Mon Jul 20, 2020 3:47 am
ECU Model: S100 Pro

Re: S100 Launch and Traction slip %

Post by John Loudon »

Thanks. Will have to experiment then...
John Loudon
Posts: 18
Joined: Mon Jul 20, 2020 3:47 am
ECU Model: S100 Pro

Re: S100 Launch and Traction slip %

Post by John Loudon »

What speed do you turn off launch at? The max speedvin first gear or less?
SMR
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Joined: Tue Jan 16, 2018 9:38 am
ECU Model: S100 Pro
Distributor: DTA
Location: Aberdeen

Re: S100 Launch and Traction slip %

Post by SMR »

Something worth noting, as re-iterated to me by Warby - clutch control (and how you release the clutch) on launch is still a key input as to how successful the launch control works. It's not just a case of holding the revs and dumping the clutch.
katana
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ECU Model: S60 Pro
Firmware Version: 29

Re: S100 Launch and Traction slip %

Post by katana »

SMR wrote: Wed Sep 08, 2021 7:25 am Something worth noting, as re-iterated to me by Warby - clutch control (and how you release the clutch) on launch is still a key input as to how successful the launch control works. It's not just a case of holding the revs and dumping the clutch.
But 9 times out of 10, that will be the most consistent method. Not the same but in Drag Racing where the launch is everything, clutches tend to be serviced every pass / 5 passes or whatever to set them exactly the same for each launch, disc wear, spring ht's, stall pressures etc. with throw away / step off clutches or relying on two step limiter held on a button. Believe it or not, vehicle launch will be micro seconds quicker if launch is controlled by finger on button or fingers holding a lever compared to foot on pedal - all down to distance from the brain! Who'd have thunk it !
Rob Stevens
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Joined: Thu Jul 28, 2011 4:10 am
ECU Model: S100 Pro
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Re: S100 Launch and Traction slip %

Post by Rob Stevens »

Yes bit lower to turn off than max speed in start gear. However if you short shift to 2nd you then get massive wheelspin as ECU doesn't know you have changed gear.
I tried convincing warby and Alex to allow launch in 1st only option but clearly never implemented. Likewise I would like to vary start line rpm vs road speed
John Loudon
Posts: 18
Joined: Mon Jul 20, 2020 3:47 am
ECU Model: S100 Pro

Re: S100 Launch and Traction slip %

Post by John Loudon »

Thanks Rob
stevieturbo
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Location: Norn Iron

Re: S100 Launch and Traction slip %

Post by stevieturbo »

SMR wrote: Wed Sep 08, 2021 7:25 am Something worth noting, as re-iterated to me by Warby - clutch control (and how you release the clutch) on launch is still a key input as to how successful the launch control works. It's not just a case of holding the revs and dumping the clutch.

There are various slipper devices on the market to allow some degree of adjustable clutch slip on launch. It can help both launch and drivetrain....with the caveat that is is not quite so friendly to the clutch itself.
But they are trial and error too, and the clutch itself needs to be pretty consistent over a wide range of temperatures.

This is where autos win...they naturally have a good degree of slip built in for launch, and where electric wins hands down. Their start rpm...matches the wheel speed ! Zero. They have total control over launch and slip with no disparity to make up for.

The likes of Top fuel, Funny Car etc etc...run a fixed driveline and pretty much the only thing controlling power delivery over the run is the clutch engagement.
They slip most of the track
Alex DTA
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ECU Model: S40 Pro
Distributor: DTA
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Re: S100 Launch and Traction slip %

Post by Alex DTA »

Rob Stevens wrote: Wed Sep 08, 2021 9:11 am Yes bit lower to turn off than max speed in start gear. However if you short shift to 2nd you then get massive wheelspin as ECU doesn't know you have changed gear.
I tried convincing warby and Alex to allow launch in 1st only option but clearly never implemented. Likewise I would like to vary start line rpm vs road speed
You did convince me, I just haven't had time to implement either.
RPM vs speed is going in to the T Series this year.
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