2003 Ford Focus RS - sensors question ?

[Jackstrath]

So can report all is well with the focus, did another hundred or so miles issue free !

Felt brave and followed the syvecs video for setting up launch control.

Slight issue where I now realise using the gearbox speed sensor for my speedo was a bad idea !

It works ok but I know it could be better.


So currently I have my speedo going into one of the inputs but I see there is 2 designated inputs for front and rear speed?
How would I go about getting that set up? Do you tie into the abs sensors ? Can you do that and still have the abs working ?

[stevieturbo]

So can report all is well with the focus, did another hundred or so miles issue free !

Felt brave and followed the syvecs video for setting up launch control.

Slight issue where I now realise using the gearbox speed sensor for my speedo was a bad idea !

It works ok but I know it could be better.


So currently I have my speedo going into one of the inputs but I see there is 2 designated inputs for front and rear speed?
How would I go about getting that set up? Do you tie into the abs sensors ? Can you do that and still have the abs working ?

Launch control doesnt need a fancy speed input. What exactly is the problem with yours ?

You could have all 4 wheels if you want, again it depends what you're trying to achieve.

And rarely will ABS systems be happy with piggybacking onto the sensors, but it's a case of trial and error. Hall sensors might be a little more forgiving with that than VR type.

[Jackstrath]

The speed sensor is coming from the gearbox speedo drive , which is fine when the wheels arnt spinning ,

I was trying to set the launch control up to basicly limit the boost/revs untill I achieved a certain speeed , but obviously as soon as I light up the front wheels I meet my set wheel speed target with not moving more than a foot off the line

I wanted it set up so that as I started to get more momentum the rpm limiter raised and there for more power was available but that doesn't seem to be working as I thought and I'm assuming it's down to what Iv explained


I didn't think the abs would like to be piggy onto , is there any recommended speed sensors for the syvecs? jT doesn't have anything listed ?


Here's a video, launch limiter set at 4500rpm, raising to 7k as wheel speed increase

https://youtu.be/RHcIFO5ouIE

[TimH]

GPS

[stevieturbo]

The speed sensor is coming from the gearbox speedo drive , which is fine when the wheels arnt spinning ,

I was trying to set the launch control up to basicly limit the boost/revs untill I achieved a certain speeed , but obviously as soon as I light up the front wheels I meet my set wheel speed target with not moving more than a foot off the line

I wanted it set up so that as I started to get more momentum the rpm limiter raised and there for more power was available but that doesn't seem to be working as I thought and I'm assuming it's down to what Iv explained


I didn't think the abs would like to be piggy onto , is there any recommended speed sensors for the syvecs? jT doesn't have anything listed ?


Here's a video, launch limiter set at 4500rpm, raising to 7k as wheel speed increase

https://youtu.be/RHcIFO5ouIE

If you have no undriven speed reference, then use a time ramp for launch control. Trying to use driven wheel speed is not going to work for a speed ramp.

Or as Tim says, GPS could give you that undriven wheel speed reference if you cannot get one from an actual undriven wheel.

But for now just use a time ramp.

[Jackstrath]

Ok il have a play about with time ramp and see how I get on

Did this gps but that sounds expensive! Any details on where to get that?

[Slowie]

You could also try Ryan's advice here, of teeing into the + wire from a rear wheel speed sensor at the ABS ECU, and setting the input to 5V.

[TimH]

Did this gps but that sounds expensive! Any details on where to get that?

Realistic GPS options are:

• New Syvecs 50Hz GPS. Has accelerometers and G sensors. Price £750+VAT.
• Our (JTinnovations) Mini Expansion Unit. As per Syvecs unit, but also has 4 inputs, H bridge driver, EGT amp., Bosch Lambda amp and barometric pressure sensor. Price £450+VAT
• Life Racing AG50 module - £1295 + VAT.
• Plex dashes with GPS option - can transmit GPS data to ECU but I'm not 100% sure what. £1470+VAT.

May be others but not sure.

[stevieturbo]

other GPS option, I think Damian had a used GPS module for sale, one of the older ones at a lower price ? Not sure if it's still there or not.


But it will work via time, or you can try and rig up a wheel speed signal.

[Jackstrath]

Il try the time option first I think, the money would be better spent on a flex fuel sensor I think as launching the car isn't something il be doing that regularly to justify the cost of the gps unit although jti's sounds very appealing, will have a looks at Ryan's advice and see if that will work for me

Thanks for the inputs