If you are driving it genitally the ignition map wouldn't try to get too aggressive so it would probably drive just fine. However you might want to check what fuel economy you achieve on the lower octane fuel. I tried running 87 in my 98 740iL with the M62 engine, and driveability was fine but average fuel economy took a dive, it went from my normal average of 20-21 down to 13-14. I am willing to bet the S62 engine with an 11:1 compression ratio wouldn't help matters over the M62's 10:1.
Quoted for posterity...If you are driving it genitally...
Four years for me and I'm lucky to get 21-22mpg. :angel:My personal best was 23 mpg over about 400 miles a couple weeks back. Was doing 70-90 most of the time, great road with lots of twisties and elevation changes. I have only had the car a few months though, so i dont have the restraint to get better mileage yet... Dat noise!
Remember that UK & US mpg are not the same when you get all the responsesI need to do around 2000 miles over the next 2 months in my M5. I need to do this cheaply (lol).
I'll be doing a few economy runs. What is the best economy that you have had from your M5?
a) not sure anyone that needs to run 87 can actually afford the running costs of an M5