David_Wallis

I dont suppose you know what the speed sensor input to the ecu on the sti 7 is..

IE 1 pulse per mph ?

David

johnfelstead

speed is calculated from the number of pulses per second, the gearbox just gives a set pulse rate per revolution or the output shaft, then the ECU/Dash electronics translates this into a speed value.

so its not pulse per mph, its pulse per output shaft revolution.

The pulse rate to distance and therefor speed varies depending on the tyres in use, i use some software for TSD rallies that has corection factors in it for tyre size, you typically have to multiply pulse rate by 0.000243659665004133 to give the distance/speed in miles.

[Edited by johnfelstead - 9/19/2003 2:52:30 PM]

David_Wallis

ok so how do I work it out for my new ecu?

David

johnfelstead

what exactly do you want david?

David_Wallis

my cake and to eat it..

my new ecu (autronics) can take a speed sensor input for datalogging and for traction control...

my new gearbox has the sti7 speed sensor in it, which drives my speedo fine, I would like to take the square wave and input it to the ecu but would like to know what Im dealing with and not being able to monitor the output and get a scope on it is kind of hindering me.

David

johnfelstead

if you read this you should be able to see how you can turn your laptop into a device to read the speed pulse rate.

http://www.drizzle.com/~glenn/tsd/setup.htm

David_Wallis

no mention of pulses per mph as yet... will look at code.

johnfelstead

of course not, its a package to make a rally computer out of your laptop, but from the info there you should work out how to get what you want.

David_Wallis

I know.. Ive seen the site before


Hows the car anyway?

johnfelstead

Flying, went a treat at the ring this weekend.