S100 Launch and Traction slip %

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John Loudon
Posts: 29
Joined: Mon Jul 20, 2020 3:47 am
ECU Model: S100 Pro

S100 Launch and Traction slip %

Post by John Loudon »

Hi,

Can anyone please recommend some good slip % settings for both Launch and Traction (dry and wet)?

Car is an 1100cc motorcycle engined single seater

Thanks

John
John Loudon
Posts: 29
Joined: Mon Jul 20, 2020 3:47 am
ECU Model: S100 Pro

Re: S100 Launch and Traction slip %

Post by John Loudon »

Sorted now thanks
SMR
Posts: 137
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 »

Out of interest John, what %slip did you end up targeting?
John Loudon
Posts: 29
Joined: Mon Jul 20, 2020 3:47 am
ECU Model: S100 Pro

Re: S100 Launch and Traction slip %

Post by John Loudon »

30%
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 »

I always messed around in the 10-20% range or less, should have tried a wild 30%, perhaps that's why my starts are no good. Trouble is the slip ratio you need is dynamic and hard to pin down, you will note that F1 cars must slip about 5% as there appears no slip
SMR
Posts: 137
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 »

Thanks John, we've been trying around 12-15%, but need to try some extreme settings as well!
John Loudon
Posts: 29
Joined: Mon Jul 20, 2020 3:47 am
ECU Model: S100 Pro

Re: S100 Launch and Traction slip %

Post by John Loudon »

I haven't yet tried it but others tell me that's what they use. Different engines and torque outputs presumably require different amounts
Rob Stevens
Posts: 1247
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 »

Don't forget the slip target isn't really a target (it's poorly worded) as you would need a PID loop to control it, it's more like a ratio where the random cut patterns become active. You need to log the slip % to see what you are actually getting.

The slip % you need is more to do with the optimum slip ratio for the tyre and road surface combination, i.e. in the wet you are looking for next to no slip.
John Loudon
Posts: 29
Joined: Mon Jul 20, 2020 3:47 am
ECU Model: S100 Pro

Re: S100 Launch and Traction slip %

Post by John Loudon »

@Rob - what sort of start times do you normally achieve and at what slip % I can confirm that 30% was not much use and reducing it to 20% was only marginally better. Still nowhere near the first 64 ft times I was hoping for (2.0x or below as opposed to 2.2x and 2.3x)

I have the speed at which to turn it off at set to below the max speed in first gear as I am usually slightly short shifting from 1st to 2nd off the start which then would mean the gear change would be within the speed range without doing so. I have teh start line RPM set at 7000rpm as its an 1100 motorcycle engine with not a lot of torque

Any tips on how to get the best out of it please?
stevieturbo
Posts: 3577
Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: S100 Launch and Traction slip %

Post by stevieturbo »

trial and error.

launching with as low a rpm as possible, perhaps allow some clutch slip to soften the hit, etc etc.
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