Astra/ corsa b speedo

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ukhozi
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Astra/ corsa b speedo

Post by ukhozi » Wed Nov 11, 2015 7:19 pm

I have a Astra GTE speedo and tried using an aftermarket sender for speedo but can't get anything near the correct speed.
Does the sensor output have to go via a ECU?
I was hoping it was analog like the MG Maestro one I had before which was 8 pulses per rev. Is there an aftermarket transponder that works at wheel speed as I need to take it from the front wheel, no gearbox take off point. 740 revs per mile.


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1995 Corsa B C14SE SPORT.
1987 BMW E30 320i auto
1987 Mercedes 2.3-16v Cosworth
2001 Mercedes A170 CDi LWB Elegance
1995 Eagle SS VW 1641cc kit car
1999 Suzuki AN400 (425)
I know, too many.

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ukhozi
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Re: Astra/ corsa b speedo

Post by ukhozi » Wed Nov 11, 2015 8:45 pm

Also, anyone know what the little red slide switch on top of the speedo is for?

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1995 Corsa B C14SE SPORT.
1987 BMW E30 320i auto
1987 Mercedes 2.3-16v Cosworth
2001 Mercedes A170 CDi LWB Elegance
1995 Eagle SS VW 1641cc kit car
1999 Suzuki AN400 (425)
I know, too many.

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coupe77
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Re: Astra/ corsa b speedo

Post by coupe77 » Wed Nov 11, 2015 8:50 pm

You need the gte transponder as the dash takes the pulse from that
It has 3 wires
You might have to fit the early cable box
Or find out what the wires on the corsa transponder do then work out the pulse wire to the speedo
Other hub speed sensors take the pulse from the abs ecu


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ukhozi
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Re: Astra/ corsa b speedo

Post by ukhozi » Thu Nov 12, 2015 11:34 pm

No GM gearbox to fit transponder to. It will have to be front wheel driven.
Apparently the switch gives a change of 2.56:1 ratio difference for the same pulses.

Sent from my Vodafone Smart 4 turbo using Tapatalk
1995 Corsa B C14SE SPORT.
1987 BMW E30 320i auto
1987 Mercedes 2.3-16v Cosworth
2001 Mercedes A170 CDi LWB Elegance
1995 Eagle SS VW 1641cc kit car
1999 Suzuki AN400 (425)
I know, too many.

User avatar
ukhozi
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Posts: 112
Joined: Thu May 26, 2011 4:30 pm
Location: Estepona, Spain

Re: Astra/ corsa b speedo

Post by ukhozi » Tue May 10, 2016 3:14 pm

Still slogging on, I now know the transponder for the speedo takes its pulses from a gear in the gearbox, as it counts the number of teeth. so what gear is it or is it a sensor ring and how many teeth so I can then fit the corrected number of teeth to my front hub LIKE an ABS ring.
1995 Corsa B C14SE SPORT.
1987 BMW E30 320i auto
1987 Mercedes 2.3-16v Cosworth
2001 Mercedes A170 CDi LWB Elegance
1995 Eagle SS VW 1641cc kit car
1999 Suzuki AN400 (425)
I know, too many.

User avatar
ukhozi
CB-Uk User
Posts: 112
Joined: Thu May 26, 2011 4:30 pm
Location: Estepona, Spain

Re: Astra/ corsa b speedo

Post by ukhozi » Sun Mar 04, 2018 8:45 pm

Still no answer.

How many pulses are needed to get the GTe speedo to read 60mph?

How I get those pulses will be down to me but I still need an answer.

I have been told that I should be looking at 15,000 ppm
÷ by 750 wheel revs pm that gives 20 pulses per wheel rev.

Help!
1995 Corsa B C14SE SPORT.
1987 BMW E30 320i auto
1987 Mercedes 2.3-16v Cosworth
2001 Mercedes A170 CDi LWB Elegance
1995 Eagle SS VW 1641cc kit car
1999 Suzuki AN400 (425)
I know, too many.