Page 1 of 2

m800 advice

PostPosted: Mon Jan 05, 2009 3:25 am
by prostang
hi all
i am looking to switch from autronic to motec m800. i run a davis traction control box that puts out a 12v signal when i have wheel spin i require this to go to the ecu to take timing out, when the 12v is removed ramp the timing back in over a 1/10th second. will the motec do this.

regards

steve

Re: m800 advice

PostPosted: Mon Jan 05, 2009 3:29 am
by IDP
Yes it will, no problem.
It will also handle all TC calculations itself if you get rid of the TC box.

Re: m800 advice

PostPosted: Mon Jan 05, 2009 3:39 am
by prostang
hi
being a drag car normal wheel sensor traction control is no good, this box works on prop shaft speed and can sence slip to 1/64th of a single turn of a wheel.
how would i set it up in the software

Re: m800 advice

PostPosted: Thu Jan 08, 2009 2:49 pm
by MarkMc
Hello,
it will not matter if you are using prop shaft speed or wheel speed you can cater for both. My question would be do you have front wheel speed sensors as well as the prop shaft speed? To know wheel slip you have to know how fast the car is moving across the ground (Ground Speed) and the speed of the driven wheels (Drive Speed), minus one away from the other and you have slip...the ECUs traction control function is there to control slip to a user defined table.

The other way if you do not have front wheel speed sensors is either RPM rate of Change or Speed rate of change but these are not as good as a proper slip calculation.

Re: m800 advice

PostPosted: Fri Jan 09, 2009 6:03 am
by prostang
hi mark
no just prop shaft only look up http://www.moretraction.com on the web to see how it works, will it work with the motec m800, on the msd set up i had on 12v imput it took out a set amount of timing say 5 deg them on removal of the 12v sgnal it ramped the timing back in over time, can this be done with the m800

Re: m800 advice

PostPosted: Fri Jan 09, 2009 8:00 am
by IDP
The M800 can do the same calculation as your TC box is doing using prop speed and RPM only
It can however do a proper slip calculation between the rolling and driven wheels if sensors are fitted.
Both methods in the ECU will work much better as it uses a PID algorithym to control the slip.

If you wish to use your system though it is very easy to connect to an unused AV input and assign it to a Ignition comp table. there you can insert however much retard you require.

Re: m800 advice

PostPosted: Fri Jan 09, 2009 9:29 am
by prostang
talked to the man who makes the box he says he can change it so it gives a 0-5 volt ouput ov no slip 5v max slip
can i link this to a table in the m800
ov no retard
1v 2deg retard
2v 3deg retard
3v 4deg retard
4v 5deg retard
5v 6deg retard

steve

Re: m800 advice

PostPosted: Fri Jan 09, 2009 12:49 pm
by stevieturbo
I think the simple answer is yes....


But Motec's own traction control is better.

Re: m800 advice

PostPosted: Fri Jan 09, 2009 6:29 pm
by Apex Speed Tech
There's no comparison in terms of traction control abilities. With MOTEC you log all the relevant inputs, outputs and calculations. This is imperative to tuning traction control. The minute you let another product do that you give up the ability to really know what's going on. Furthermore, MOTEC's innovative user-defined axis allow you to build your own strategies which can be very advantageous.

Comparing a timing retarder that uses nothing but rate-of-change of engine RPM to the MOTEC traction control is comparing apples to oranges.

-Neel

Re: m800 advice

PostPosted: Fri Jan 09, 2009 6:36 pm
by IDP
prostang wrote:talked to the man who makes the box he says he can change it so it gives a 0-5 volt ouput ov no slip 5v max slip
can i link this to a table in the m800
ov no retard
1v 2deg retard
2v 3deg retard
3v 4deg retard
4v 5deg retard
5v 6deg retard

steve


This is simple to implement into an Ignition compensation table.