Speedometer recalibration?

BKOMAR · BKOMAR's Garage

Just got my new tires...KUMHO ECSTA's (40's)...what a difference! I really like them! Just over $400.00 at my local (small town) tire dealer. Now....my speedo is waaaay off! I was wondering if there is a device that can be put in line that is like a gear reducer or something that will put the speedo back to stock with the 40 tires. Or... is there a way to recalibrate the speedo? I can only put 7000 miles a year on the car (insurance deal) and I am racking up the miles now faster than I actually am driving... I dont want that! Thanks for any input! Brian

89Targa · 05-08-2002, 12:01 PM

The VDO speedometers can be recalibrated. There are several threeds on this topic. Check the archives.

A well regarded shop is Palo Alto Speedometer in California. Their web site describes the info they need to recalibrate. Check them out at:

www.paspeedo.com

Good luck,

TimT · 05-08-2002, 03:58 PM

also north hollywood speedo I think the advertise in pano and excellence

just pull the speedo and send it out, tell them the tire size and they will calibrate it

epbrown · 05-08-2002, 04:01 PM

How long does the recalibration take? I've got a set of 16" wheels coming in next week.

Emanuel

89Targa · 05-08-2002, 04:07 PM

The actual work probably takes about an hour. The variable is their backlog. Call Palo Alto or Hollywood (they both advertise in Pano)in advance to work it out.

mm86911 · mm86911's Garage

I'm in a similar situation as my differntial gear is now 7.31. Does/has anyone recalibrated a Carrera speedo themselves?

epbrown · 05-08-2002, 07:26 PM

I just check the UPS web site, and the 16" Fuchs I bought on eBay are already here in Chicago! (Seller shipped them on Tuesday). Odds are I'll be getting them tomorrow morning, which means I could have them mounted on the car (they're coming with practically new Bridgestone Potenzas on them) by the weekend for another trip to KY.

Highway driving with an inaccurate speedo in a Porsche - could be trouble

In a city the size of Chicago, there should be some place that could change the speedo for me here in town. Any ILans know of a place? Can a Porsche dealership do it?

Or, anyone have an idea how much the speedo will be off going from 15" to 16" wheels? I thought it changed the gearing 4%, so would cruising with the speedometer reading 60 mph actually be 62.4 mph? While my mileage of 400 miles would read as 416 on the clock? Or is it more complicated?

Emanuel

CamB · CamB's Garage

The speedo should be off 0.

205/55R16 is the same (more or less, like 1% difference) diameter as 185/70R15.

225/50R16 is the same as 215/60R15.

epbrown · 08:27 PM

Cool. I see what you did now. I was focusing on the width of the new tires, and didn't notice that they were lower profiles, so that even though the rim is an inch larger in diameter, the entire circumference is only increasing by ~5mm, which is pretty negligible. Thanks.

Emanuel