keithl

Back in the day I thought the car rags used to show in their testing actual vs. speedo readings and I remember them also were be off by 1-2 MPH on the high side.

irenesbob

I Googled the issue of the accuracy of car vs. GPS speeds and the “experts” seem to conclude that GPS is indeed more accurate. I will buy that as a good general rule.
As far as odometer readings are concerned I still occasionally record and compare my car’s odometer reading over a long distance with the highway mile posts. On an interstate (like I-87 north form Albany NY to the Canadian border) one can do this for a long (150 mile-plus) distance to minimize errors. I don’t recall what the result was for my current A6, but there was difference.
Another thing I do (assuming there are no traffic issues) is clip the apex on turns so that a trip like I mentioned is cut somewhat. It is minimal, but could save 1% on a long trip. Police don’t like seeing you go to the outside, and then cut across for what appears to be no reason (or maybe it looks like a stoned driver), but sometimes I risk it. The idea is to make your route as close to a straight line as possible, since the turns add distance actually traveled, while not getting you closer to the end destination. I first became aware of this in the old Trans Am series when I watched Mark Donahue in his AMC Javelin (I think that is what he drove) catch up to George Follmer in his Mustang at Bridgehampton by clipping/cutting all the apexes and thus shortening the distance traveled. The idea stuck with me and I occasionally will still do this; however, it then screws up your odometer accuracy. Can’t have things both ways, I guess.

irenesbob

That's a whole other issue. Back in the day the auto rags (Consumer Reports included) gave a lot of metrics for the enthusiast to consider. Today so much is subjective and the judgments expressed in the write-ups sometimes are not supported by what little data they do offer. Our society has moved from one that utilizes details and facts to one that treasures "feelings" - IMHO. I long for the days when you could open an annual car issue and compare front/rear legroom, headroom, trunk capacity, ground clearance, etc. and discover what worked for you and what didn’t without having to go to multiple sources. Road and Track still offers a lot of this, but their penchant for putting the dark print in the tabular presentation against sexy dark background colors makes it difficult to read. Form not following function.

keithl

Ditto! I care what some guy that spends 1 or a few days in 100+ cars a year to tell me how he feels about it, tell me when you drive the same car day in and out for a year. Give me the specs i need to make and educated decisions on the specs then I will decide how I feel about the car and ride when I drive it.