General FL 5 (and other models?) range.

[Rolfe]

Don't forget your speedo is very accurate. Your last ICE vehicle probably overread by about 10% at 75mph so actually only doing 70 or less.
I notice this when setting the ACC to 65mph on motorways and find I'm slowly passing other vehicles that obviously have their cruise control set at 70mph.

I don't think you'll pass people who are set to 70 if you're set to 65, but yes if they're also set to 75. I think the speedos in my ICE cars have over-read by 2 or 3 mph, not by a percentage.

Remember also that the MG4's mile measurement is an over-estimate. Bjorn reckons 2.4%. I would tend to concur, although the percentage seemed to vary a bit depending on the distance. But if your car thinks you have gone 100 miles you've probably done about 97.5 miles or so.

 

[Gomev]

I don't think you'll pass people who are set to 70 if you're set to 65, but yes if they're also set to 75. I think the speedos in my ICE cars have over-read by 2 or 3 mph, not by a percentage.

Remember also that the MG4's mile measurement is an over-estimate. Bjorn reckons 2.4%. I would tend to concur, although the percentage seemed to vary a bit depending on the distance. But if your car thinks you have gone 100 miles you've probably done about 97.5 miles or so.

I do pass people, maybe they have their cruise set to 68mph. My last ICE overread by about 10% over 70 mph compared to GPS reading, I could easily set it at 80 and not upset any bobbies on the M'way.
I have found the overreading to be incremental in that at 30mph very little, and difference greater as the speed grew.

 

[Rolfe]

I pass people too, but obviously I can't know what they have their speed set to. Bobbies will ignore you up to the speed limit plus 10% plus 2 mph, or I think I read that changed to 1%. I used to feel safe with the speedo at 80 but maybe not entirely in the MG4.

 

[tsedge]

I do pass people, maybe they have their cruise set to 68mph. My last ICE overread by about 10% over 70 mph compared to GPS reading, I could easily set it at 80 and not upset any bobbies on the M'way.
I have found the overreading to be incremental in that at 30mph very little, and difference greater as the speed grew.

This is also my experience with ICE cars, typically true 70 was 77 or 78 indicated. The MG4 is different.

 

[Rolfe]

I set my ACC at 80 on the M74 to see what would happen. I wasn't outdistancing everyone there, by any means, and I didn't feel as if I was going much more than when I was trying to hold to 80 on my previous cars.

Once, on the M6, I passed a cop car and immediately held myself to 80 on the speedo. I wasn't the only one, and soon there was a cohort of cars driving en bloc at 80. I was middle lane, in the front. It was hellish tempting to push on as I had a very long journey ahead, but I really didn't want points on my licence so I held it down.

Gradually it got dark, and I could no longer see the cars behind, only their headlights. Was the cop car still there? It had been a long way. Wouldn't he be out of his stamping ground? I went on deciding not to risk it, as did the other cars in the group. Until suddenly a car on my right shoulder obviously had enough, and accelerated fast past me and into the open road ahead. Immediately one of the other sets of headlights sprouted red and blue flashing lights and a police siren. The one who broke ranks was bang to rights, and was stopped. 80 on the speedo had worked, more than that, no.

The rest of us heaved a sigh of relief and hurried on our way.

I think setting ACC at 80 might be a bit of a risk on the MG4 though. On the other hand I encountered a mobile speed unit in Edinburgh in the MG4, in a 30 mph zone. I think I had 37 on my speedo when I saw him and thought, oh hell. 34 or 35 is the most you're supposed to get away with in a 30 mph zone. But I didn't get nicked. Just lucky that day I guess.