Skipping firing cycles will cause unburnt mixture to be pumped into the exhaust which could cause some nice loud back fires.  This is never very good for exhaust valves, or indeed the the exhaust system itself.  This method used to be used by add-on rev-limiters, but much better methods exist.  One traction control system I have seen actually uses a secondary throttle which is normaly wide open, but can be closed by a servo to back off power.

Mike

-----Original Message-----
From:   Allen Demers [SMTP:farmbooy@IX.NETCOM.COM]
Sent:   Wednesday, May 03, 2000 2:53 PM
To:     PICLIST@MITVMA.MIT.EDU
Subject:        Re: Ignition timing, 2nd iteration....

Andy,

To avoid too much lag I wonder if this would work.

How about just skipping the firing of a plug... like an interupt.  You
could detect rotation ratio front to back and if it is way out of sink
you could interrupt the firing of the next plug?  Dont know if this
mechanicaly would be detrimental.

<SNIP>
>I'm just thinking out loud here. Since you have maximum traction when
>there's no wheelspin, maybe you could devise a system that compared the
>rotation of the front and rear wheels and slightly backed off the
>throttle if it detected any slipping, checked again and backed off if...
>etc.