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Old 12-02-2012, 03:40 PM
Terry @ BMS Terry @ BMS is offline
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Originally Posted by White05X3 View Post
Terry - what are the knock counts with the mix of 91 and 100 on the race fuel map? Would you feel comfortable running this combo on a race track (a real one...where you actually turn the steering wheel and a session lasts longer than 15 seconds) in 100 ambient temperatures? What is the minimal safe ratio of 91:100 for use on a race track?
The BMW DME doesn't use knock count system per say. Rather a full adaptive timing system with long term octane trims and shorter term knock trims. The fuel mixture and actual tune settings used depend on your particular objectives. Using the +7psi settings in the dyno above I would suggest at least 97 RM2 octane. Using the default +3psi setting 91-93 octane is acceptable.

For road racing where consistency is king I'd normally suggest using a pump gas map w/ race gas for extra insurance to ensure timing is continuously maxed out for consistent performance.

The race maps are more for those who are interested in drag racing. Which involves runs less than 15 seconds, without turning the wheel, where HP reins supreme. Does not appear to be your thing but appeals to a large segment of the enthusiast base...

Last edited by Terry @ BMS; 12-02-2012 at 03:42 PM.
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