According to Einstein, at the speed that some of you guys (I'm talking to you Darell) claim to go in your T5's, it is not surprizing that the clocks run slow. In fact, with a K&N filter, custom exhaust and a "chip" it would be possible to return before you set out. Alas, it doesn't account for the error on my XC.
I'm gonna try driving only in reverse tomorrow.<P>Hmm. How fast have I been claiming to drive? My top so far is 121 mph (GPS verified!) And I KNOW I'm not alone at that speed. I rarely go over 100 on a daily basis though. But heck, who's gonna pull over a station wagon? <IMG SRC="http://www.swedespeed.com/ubb/smile.gif"><P>BTW, I'm happy to report that according to my GPS, my speedo is accurate to within 1 mph through all of the range I've tested.<P>- Darell
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by darell:<BR><B>How fast have I been claiming to drive? My top so far is 121 mph (GPS verified!) And I KNOW I'm not alone at that speed. I rarely go over 100 on a daily basis though.<BR>- Darell</B><HR></BLOCKQUOTE><P>Damn, 121 mph is pretty fast! The fastest I have ever gone is like 100 mph, and that was a joyous occasion for me! I guess I am too scared. <IMG SRC="http://www.swedespeed.com/ubb/wink.gif"><P>-Drew<BR>
The only thing I'm scared of at 100 is the police. I feel more confident doing 100 in this car (even in the rain!) than I felt doing 80 in our old Accord.<P>But now I realize everybody's gonna think I'm some Boy Racer who thinks he's still in high school. Well, that's just not true....I think of myself at LEAST being in college.<P> <IMG SRC="http://www.swedespeed.com/ubb/smile.gif"><P>- Darell
You mentioned speedo accuracy, in passing, Darell - using the GPS which I assumed is accurate . . . ? But others I have read about have found 6 or 7 % errors, using identical car electronics. This is puzzling: it's all in software and yet the timing is different. Perhaps there is some adjustment of accuracy, otherwise we would all have exactly the same accuracy. Just a thought, but I don't think there will be a solution from Volvo. It's interesting that your GPS gives additional features than telling you how to get to a restaurant. Any other things it can do that you have not told us about?
Hmmm. I haven't heard too many people complaining about innacurate speedos on the new V70s. What does everybody else here think? <P>Tire size is the one big, user-selectable variable here. I'd guess the rolling diamter of the two factory wheels sizes will be a few percent different. That would directly translate into speedo offset.<P>As for my GPS goodies:<BR>It shows me where in the sky all the satellites are that it's reading, how strong their signals are, real-time positional error, when sunrise and sunset are, the current time (set by the Colorado atomic clock), the amount of time I've been moving, the amount of time I've been stopped (since the last reset), the top speed, the average speed (including and excluding you're stopped time), current speed, my compass bearing.<P>And it shows where all the McDonald's are.<P>It's a fun toy. I just received my unlock code for the entire country, so I'm set to go anywhere.<P>- Darell
I've read on the Vortex that VW Passat's speedo has a built in positive error of 5 MPH or so to discourage speeding. Perhaps the V70 has the same?<P>Interesting:<BR> <A HREF="http://forums.vwvortex.com/vwbb/Forum6/HTML/014626.html" TARGET=_blank>http://forums.vwvortex.com/vwbb/Forum6/HTML/014626.html</A>
Certainly not in my car. And my car has the "standard" wheels/tires for the T5. It would only make sense that they would set the speedo for that rolling diameter. It would be tough to maintain that accuracy across other wheel/tire combinations.<P>- Darell
Darell, if your speedo is accurate with the stock T5 tires as the Volvo base design, and accepting as a fact that the XC speedometer reads 4-5 mi/h high at 60 mi/h, all other things in the electronics being equal, the diameter and therefore the rolling circumference of the Scorpion tires (16" wheels) would have to be a 4-5% less than the T5 tires. So what do you and the students of tire dimensions reckon?
The only thing I can reckon is that the XC tires are, in fact, the same percentage smaller in diameter as the speedo error. 4-5 mph error at 60 is a bit higher than 5% error though.<P>One thing to keep in mind, is that two tires (even different models from the same mfg) with the same diameter, width, and profile will always vary (at least somewhat) in rolling diameter. Sometimes greatly. I have personally had a 1" difference on 15" tires from different mfg's that had identical numbers on the sidewall.<P>It would be interesting to see if the XC's speedo offset percentage remains constant throughout the speed range (Most of my other assumptions are based on THAT assumption). If you check at 100 mph, the percentage is easiest to calculate <IMG SRC="http://www.swedespeed.com/ubb/smile.gif"><P>- Darell