Jaycar Speed corrector in Ford AU

[Uncle Al]

Hi all,

I've got an Ford AU3 Fairmont that has aftermarket rims/tyres.
This throws the speedo out by about 10%.

I am trying to sort out whether a Jaycar speed corrector
(http://tinyurl.com/dblvbw) will sort out the speedo error without
incurring other issues.

Other issues may be shift points for the auto transmission and/or
problems with cruise control.

I've hunted around the net looking for answers and came across a post
where someone suggests that to control shift points it may require TWO
speedo correctors.
First corrector to drop the signal from the auto transmission to the
speedo and the second corrector to increase the signal from the speedo
to the ecu.

Can any of you electronic boffins shed some light on this for me.

I'm competent to assemble and install the kit but when it come to
understanding electronics I'm lost.

Thanks for reading.

 

[Davo]

Uncle Al wrote:

Hi all,

I've got an Ford AU3 Fairmont that has aftermarket rims/tyres.
This throws the speedo out by about 10%.

I am trying to sort out whether a Jaycar speed corrector
(http://tinyurl.com/dblvbw) will sort out the speedo error without
incurring other issues.

Other issues may be shift points for the auto transmission and/or
problems with cruise control.

I've hunted around the net looking for answers and came across a post
where someone suggests that to control shift points it may require TWO
speedo correctors.
First corrector to drop the signal from the auto transmission to the
speedo and the second corrector to increase the signal from the speedo
to the ecu.

Can any of you electronic boffins shed some light on this for me.

I'm competent to assemble and install the kit but when it come to
understanding electronics I'm lost.

Thanks for reading.

What about putting the correct size tyres on?

 

[atec 7 7]

crazyclark wrote:

Davo wrote:
Uncle Al wrote:
Hi all,

I've got an Ford AU3 Fairmont that has aftermarket rims/tyres.
This throws the speedo out by about 10%.

I am trying to sort out whether a Jaycar speed corrector
(http://tinyurl.com/dblvbw) will sort out the speedo error without
incurring other issues.

Other issues may be shift points for the auto transmission and/or
problems with cruise control.

I've hunted around the net looking for answers and came across a post
where someone suggests that to control shift points it may require
TWO speedo correctors.
First corrector to drop the signal from the auto transmission to the
speedo and the second corrector to increase the signal from the
speedo to the ecu.

Can any of you electronic boffins shed some light on this for me.

I'm competent to assemble and install the kit but when it come to
understanding electronics I'm lost.

Thanks for reading.





What about putting the correct size tyres on?

Sure, that's always an option but given that the rims and tyres fall
within the legal size for my car, it's good to individualise a little...

Got a clue with regard to the question?
Swap the gearbox sender to one which suites is much better.

 

[rebel]

On Sat, 02 May 2009 14:01:55 -0700, Uncle Al <uncle@al.com> wrote:

Hi all,

I've got an Ford AU3 Fairmont that has aftermarket rims/tyres.
This throws the speedo out by about 10%.

I am trying to sort out whether a Jaycar speed corrector
(http://tinyurl.com/dblvbw) will sort out the speedo error without
incurring other issues.

Other issues may be shift points for the auto transmission and/or
problems with cruise control.

I've hunted around the net looking for answers and came across a post
where someone suggests that to control shift points it may require TWO
speedo correctors.
First corrector to drop the signal from the auto transmission to the
speedo and the second corrector to increase the signal from the speedo
to the ecu.

Can any of you electronic boffins shed some light on this for me.

I'm competent to assemble and install the kit but when it come to
understanding electronics I'm lost.

Thanks for reading.

IIRC there is a "screwdriver" adjustment in the AU. Maybe ask on a Ford forum,
or at least in aus.cars

 

[crazyclark]

Davo wrote:

Uncle Al wrote:
Hi all,

I've got an Ford AU3 Fairmont that has aftermarket rims/tyres.
This throws the speedo out by about 10%.

I am trying to sort out whether a Jaycar speed corrector
(http://tinyurl.com/dblvbw) will sort out the speedo error without
incurring other issues.

Other issues may be shift points for the auto transmission and/or
problems with cruise control.

I've hunted around the net looking for answers and came across a post
where someone suggests that to control shift points it may require TWO
speedo correctors.
First corrector to drop the signal from the auto transmission to the
speedo and the second corrector to increase the signal from the speedo
to the ecu.

Can any of you electronic boffins shed some light on this for me.

I'm competent to assemble and install the kit but when it come to
understanding electronics I'm lost.

Thanks for reading.





What about putting the correct size tyres on?

Sure, that's always an option but given that the rims and tyres fall
within the legal size for my car, it's good to individualise a little...

Got a clue with regard to the question?

 

[mark brothers uncle]

atec 7 7 wrote:

crazyclark wrote:
Davo wrote:
Uncle Al wrote:
Hi all,

I've got an Ford AU3 Fairmont that has aftermarket rims/tyres.
This throws the speedo out by about 10%.

I am trying to sort out whether a Jaycar speed corrector
(http://tinyurl.com/dblvbw) will sort out the speedo error without
incurring other issues.

Other issues may be shift points for the auto transmission and/or
problems with cruise control.

I've hunted around the net looking for answers and came across a
post where someone suggests that to control shift points it may
require TWO speedo correctors.
First corrector to drop the signal from the auto transmission to the
speedo and the second corrector to increase the signal from the
speedo to the ecu.

Can any of you electronic boffins shed some light on this for me.

I'm competent to assemble and install the kit but when it come to
understanding electronics I'm lost.

Thanks for reading.





What about putting the correct size tyres on?

Sure, that's always an option but given that the rims and tyres fall
within the legal size for my car, it's good to individualise a little...

Got a clue with regard to the question?
Swap the gearbox sender to one which suites is much better.

That's interesting, thanks for that.

In the past I've changed speedo gears in manuals but wasn't aware that a
similar (if different) proposition was possible with auto's.

Can you elaborate a little as to where I'd chase it up and what I'd ask
for when I get there?

(Is it simply a matter of saying that my speedo reads 10% high and could
I have a speedo sender to suit, or is there more to it?)

 

[Mr.T]

"mark brothers uncle" <mb@u.com> wrote in message
news:0044d2e3$0$9208$c3e8da3@news.astraweb.com...

atec 7 7 wrote:
crazyclark wrote:
Davo wrote:
Uncle Al wrote:
Hi all,

I've got an Ford AU3 Fairmont that has aftermarket rims/tyres.
This throws the speedo out by about 10%.

I am trying to sort out whether a Jaycar speed corrector
(http://tinyurl.com/dblvbw) will sort out the speedo error without
incurring other issues.

Other issues may be shift points for the auto transmission and/or
problems with cruise control.

I've hunted around the net looking for answers and came across a
post where someone suggests that to control shift points it may
require TWO speedo correctors.
First corrector to drop the signal from the auto transmission to the
speedo and the second corrector to increase the signal from the
speedo to the ecu.

Can any of you electronic boffins shed some light on this for me.

I'm competent to assemble and install the kit but when it come to
understanding electronics I'm lost.

What about putting the correct size tyres on?

Sure, that's always an option but given that the rims and tyres fall
within the legal size for my car, it's good to individualise a
little...

Got a clue with regard to the question?
Swap the gearbox sender to one which suites is much better.

That's interesting, thanks for that.

In the past I've changed speedo gears in manuals but wasn't aware that a
similar (if different) proposition was possible with auto's.

Can you elaborate a little as to where I'd chase it up and what I'd ask
for when I get there?

(Is it simply a matter of saying that my speedo reads 10% high and could
I have a speedo sender to suit, or is there more to it?)

Probably cheaper and far more accurate to just use a GPS unit for speed
readout. And if your speedo reads 10% high, your just less likely to get
booked anyway!
(are you sure it's reading high though? IF your tyres are bigger
circumference it will read low. If they are lower profile and the same
width, then they would be smaller circumference and you would be correct of
course. IF they are both lower profile and wider, as is often the case with
aftermarket "upgrades", then the circumference is usually not 10% different)

And the speedo reading has *ZERO* affect on your cruise control BTW. Are you
really incapable of adding/subtracting 10% to the indicated speed when you
set it?

MrT.

 

[Franc Zabkar]

On Sat, 02 May 2009 14:01:55 -0700, Uncle Al <uncle@al.com> put finger
to keyboard and composed:

Hi all,

I've got an Ford AU3 Fairmont that has aftermarket rims/tyres.
This throws the speedo out by about 10%.

I am trying to sort out whether a Jaycar speed corrector
(http://tinyurl.com/dblvbw) will sort out the speedo error without
incurring other issues.

Other issues may be shift points for the auto transmission and/or
problems with cruise control.

I've hunted around the net looking for answers and came across a post
where someone suggests that to control shift points it may require TWO
speedo correctors.
First corrector to drop the signal from the auto transmission to the
speedo and the second corrector to increase the signal from the speedo
to the ecu.

Isn't the sensor a 3-wire Hall Effect type, in which case the signal
would be in digital form? Wouldn't it be wired directly to the ECU?

If the "someone" above is suggesting that the ECU should continue to
see the actual speed of rotation of the transmission, regardless of
road speed, then you would only need to connect the speedo corrector
between the ECU speed output and the speedometer input, assuming the
output is a pulse type.

This could be the kit -- Super Speedo Corrector:

http://www.jaycar.com.au/products_uploaded/productLarge_9901.jpg
http://www.siliconchip.com.au/cms/A_108157/article.html
http://us1.webpublications.com.au/static/images/articles/i1081/108157_3mg.jpg
http://us1.webpublications.com.au/static/images/articles/i1081/108157_4mg.jpg
http://us1.webpublications.com.au/static/images/articles/i1081/108157_5mg.jpg
http://us1.webpublications.com.au/static/images/articles/i1081/108157_6mg.jpg
http://us1.webpublications.com.au/static/images/articles/i1081/108157_7mg.jpg

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.

 

[Franc Zabkar]

On Sun, 03 May 2009 00:09:27 -0700, mark brothers uncle <mb@u.com> put
finger to keyboard and composed:

atec 7 7 wrote:

Swap the gearbox sender to one which suites is much better.

That's interesting, thanks for that.

In the past I've changed speedo gears in manuals but wasn't aware that a
similar (if different) proposition was possible with auto's.

Can you elaborate a little as to where I'd chase it up and what I'd ask
for when I get there?

(Is it simply a matter of saying that my speedo reads 10% high and could
I have a speedo sender to suit, or is there more to it?)

If your car has an option for a lower ratio differential, then you
could get the speedo sender that was designed to match it. IIRC,
common ratios for other makes (in the 70s) were 2.92, 3.23, 3.50.
These differ by about 10%.

Doing this, however, may change the shift points for your automatic
transmission.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.

 

[gets tedious don't it]

atec 7 7 wrote:

mark brothers uncle wrote:
atec 7 7 wrote:
crazyclark wrote:
Davo wrote:
Uncle Al wrote:
Hi all,

I've got an Ford AU3 Fairmont that has aftermarket rims/tyres.
This throws the speedo out by about 10%.

I am trying to sort out whether a Jaycar speed corrector
(http://tinyurl.com/dblvbw) will sort out the speedo error without
incurring other issues.

Other issues may be shift points for the auto transmission and/or
problems with cruise control.

I've hunted around the net looking for answers and came across a
post where someone suggests that to control shift points it may
require TWO speedo correctors.
First corrector to drop the signal from the auto transmission to
the speedo and the second corrector to increase the signal from
the speedo to the ecu.

Can any of you electronic boffins shed some light on this for me.

I'm competent to assemble and install the kit but when it come to
understanding electronics I'm lost.

Thanks for reading.





What about putting the correct size tyres on?

Sure, that's always an option but given that the rims and tyres fall
within the legal size for my car, it's good to individualise a
little...

Got a clue with regard to the question?
Swap the gearbox sender to one which suites is much better.

That's interesting, thanks for that.

In the past I've changed speedo gears in manuals but wasn't aware that
a similar (if different) proposition was possible with auto's.
i assume it's much the same with drive running through an adaptor

Can you elaborate a little as to where I'd chase it up and what I'd
ask for when I get there?
Well ask ford first , I have used after-market from the valley in Brisbane

(Is it simply a matter of saying that my speedo reads 10% high and
could I have a speedo sender to suit, or is there more to it?)
I supplied the required information and he came back with the righ adaptor

Thanks mate, appreciate your input.
I rem your nic from the old a2600w days - glad to see you're still
contributing

 

[suss it out]

Mr.T wrote:

"mark brothers uncle" <mb@u.com> wrote in message
news:0044d2e3$0$9208$c3e8da3@news.astraweb.com...
atec 7 7 wrote:
crazyclark wrote:
Davo wrote:
Uncle Al wrote:
Hi all,

I've got an Ford AU3 Fairmont that has aftermarket rims/tyres.
This throws the speedo out by about 10%.

I am trying to sort out whether a Jaycar speed corrector
(http://tinyurl.com/dblvbw) will sort out the speedo error without
incurring other issues.

Other issues may be shift points for the auto transmission and/or
problems with cruise control.

I've hunted around the net looking for answers and came across a
post where someone suggests that to control shift points it may
require TWO speedo correctors.
First corrector to drop the signal from the auto transmission to the
speedo and the second corrector to increase the signal from the
speedo to the ecu.

Can any of you electronic boffins shed some light on this for me.

I'm competent to assemble and install the kit but when it come to
understanding electronics I'm lost.
What about putting the correct size tyres on?
Sure, that's always an option but given that the rims and tyres fall
within the legal size for my car, it's good to individualise a
little...
Got a clue with regard to the question?
Swap the gearbox sender to one which suites is much better.
That's interesting, thanks for that.

In the past I've changed speedo gears in manuals but wasn't aware that a
similar (if different) proposition was possible with auto's.

Can you elaborate a little as to where I'd chase it up and what I'd ask
for when I get there?

(Is it simply a matter of saying that my speedo reads 10% high and could
I have a speedo sender to suit, or is there more to it?)


Probably cheaper and far more accurate to just use a GPS unit for speed
readout. And if your speedo reads 10% high, your just less likely to get
booked anyway!
(are you sure it's reading high though? IF your tyres are bigger
circumference it will read low. If they are lower profile and the same
width, then they would be smaller circumference and you would be correct of
course. IF they are both lower profile and wider, as is often the case with
aftermarket "upgrades", then the circumference is usually not 10% different)

And the speedo reading has *ZERO* affect on your cruise control BTW. Are you
really incapable of adding/subtracting 10% to the indicated speed when you
set it?

MrT.


Well... a bunch of assumptions based on what?

If I only had one set of aftermarket rims in one size with one tyre
profile and only drove it to the local shops then I may run with your
line of thinking. That ain't the case.

Obviously a closer reading of my op would clue you in that I wasn't
suggesting that the speedo reading *did* have any effect on the cruise
control.

I don't know why whether or not I'd prefer my speedo to be accurate is
worth you commenting about stuff of which you've no idea (my situation;
my preferences; whether I have a gps; whether I have a clue about tyre
sizes and speed differentials; at what speed I'm indicating a 10%
difference; whether my calculating skills are adequate etc etc) but I
guess if you've got time on your hands...

Got any input about Jaycar speedo correctors?

 

[atec 7 7]

mark brothers uncle wrote:

atec 7 7 wrote:
crazyclark wrote:
Davo wrote:
Uncle Al wrote:
Hi all,

I've got an Ford AU3 Fairmont that has aftermarket rims/tyres.
This throws the speedo out by about 10%.

I am trying to sort out whether a Jaycar speed corrector
(http://tinyurl.com/dblvbw) will sort out the speedo error without
incurring other issues.

Other issues may be shift points for the auto transmission and/or
problems with cruise control.

I've hunted around the net looking for answers and came across a
post where someone suggests that to control shift points it may
require TWO speedo correctors.
First corrector to drop the signal from the auto transmission to
the speedo and the second corrector to increase the signal from the
speedo to the ecu.

Can any of you electronic boffins shed some light on this for me.

I'm competent to assemble and install the kit but when it come to
understanding electronics I'm lost.

Thanks for reading.





What about putting the correct size tyres on?

Sure, that's always an option but given that the rims and tyres fall
within the legal size for my car, it's good to individualise a little...

Got a clue with regard to the question?
Swap the gearbox sender to one which suites is much better.

That's interesting, thanks for that.

In the past I've changed speedo gears in manuals but wasn't aware that a
similar (if different) proposition was possible with auto's.
i assume it's much the same with drive running through an adaptor

Can you elaborate a little as to where I'd chase it up and what I'd ask
for when I get there?
Well ask ford first , I have used after-market from the valley in

Brisbane

(Is it simply a matter of saying that my speedo reads 10% high and could
I have a speedo sender to suit, or is there more to it?)
I supplied the required information and he came back with the righ

adaptor