speedo off?

[Beej '86 325es]

Keep in mind that the speedos are 4mph fast. If you maintain a consistent speed and reset the average speed on the OBC, it should show about 4 mph slower than the speedometer. I believe BMW used to do this to prevent people from speeding so much. I don't know if they still do this or not.

Is this true for all e30s? Are you just basing this off of the OBC measurement, or have you read documentation regarding it? I've noticed when driving past the police radars that they'll read a bit slower than my spedo shows.

I haven't seen official documentation on this. But back in the day, and it might not have been on this board, maybe on BEN...there was a big thread where a lot of people all checked and we were all 4 mph fast. A couple of people "confirmed" that BMW had done this intentionally.

[george graves]

4 mph fast at what speed? Above 20? 30? 40? 50 MPH? Cause It doesnt read 4 MPH faster when I'm stopped!

[Digitalwave]

I believe at 60mph.

[turnofftheradio]

4 mph fast at what speed? Above 20? 30? 40? 50 MPH? Cause It doesnt read 4 MPH faster when I'm stopped!

:D

now, as I think of it, my mpg on my obc must be wrong since it thinks I'm getting 10 mph faster? wish my odo worked to test this... avg 28.6mpg. thought that was too good to be true