CMC Wide body, speedometer reads from 5 - 15 mph faster that actual speed. Is there a way to adjust the meter or change the drive gear on the front wheel to adjust this?
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CMC Wide body, speedometer reads from 5 - 15 mph faster that actual speed. Is there a way to adjust the meter or change the drive gear on the front wheel to adjust this?
what kind of speedo is it? Mech. or electric?
Jeff,
I ran across this website when I was looking to have mine calibrated. It has same problem as yours. I ended up getting the replica 356 Porsche guages.
It might be worth checking with them for a Ratio Adaptor.
http://www.a1electric.com/speedometer.htm
Greg B
I ran across this website when I was looking to have mine calibrated. It has same problem as yours. I ended up getting the replica 356 Porsche guages.
It might be worth checking with them for a Ratio Adaptor.
http://www.a1electric.com/speedometer.htm
Greg B
Typical front wheel cable drive (mechanical). Any thoughts?
Still need to know make/type speedo as many take the drive cable signal and convert it to electric impulses vice spinning the speedos internal gears. Guess you could always change the speedo face to match actual readings. Are your tires larger than 165x15 and is that reason for difference? If so go to a lower aspect ratio tire -- there is a miata site www.miata.net/garage/tirecalc.html that gives tire size info and speed variences.
Wouldn't his tires have to smaller (in diameter) to result in speedo reading high?
I've got 55 or 50 series on my car and its always read high...figured that's why.
I've got 55 or 50 series on my car and its always read high...figured that's why.
On our mechanical speedo gauges, it could be a buildup of friction inside (dirt, rust, dead rodents?) I'd Google to Hollywood Speedo - NO, NOT the bathing suit maker! That is their only business.
Speedometer is the VDO unit that came with the CMC kit when it was purchased in 1991.
The caar has 8400 miles on it according to the faulty gauge.
The car is the wide body style and the builder had put 15" WELD racing wheels on it mounted with 205/50/15 tires.
The caar has 8400 miles on it according to the faulty gauge.
The car is the wide body style and the builder had put 15" WELD racing wheels on it mounted with 205/50/15 tires.
Jeff, sounds like the same problem I have...I've got the same size tires and my speedo reads high.
I thought that if I just calculated the circumference of my tires and compare to the circumference of the tires that came with the car that the speedo is from then I could arrive at a % difference and apply that to the faulty reading to arrive at a somewhat more accurate reading. Does this make sense?
Brian
I thought that if I just calculated the circumference of my tires and compare to the circumference of the tires that came with the car that the speedo is from then I could arrive at a % difference and apply that to the faulty reading to arrive at a somewhat more accurate reading. Does this make sense?
Brian
Makes sense, and can do. My problem is that I got a speeding ticket and was told by the officer that I could get it rescended if I got the speedometer re-calibrated and showed the reciept. Tried to talk her into a warning only but she must have been under quota that day.
She did enjoy looking the car over, sitting in it and starting it up and reving the engine to hear the megaphone exhaust (no mention of how LOUD it was, just a big grin).
She did enjoy looking the car over, sitting in it and starting it up and reving the engine to hear the megaphone exhaust (no mention of how LOUD it was, just a big grin).