I posted a similar thread in the road racing forum but didn't get any replies there so I thought I would start a new thread in here.

I have been taking my R56 MCS to the track whenever possible lately. I am hearing a relatively loud knocking noise when the engine is running idle at around 800 to 900 rpm at the end of the track day. If I get on the throttle and increase the rpm a bit, the noise completely disappears. I am not an expert on engines but after some Google search, I have found out that this problem happens on some other cars too after autocross or track driving and I think it is a problem described as "lifter knock noise". Do any of you guys who also run R56s on a track hear a similar noise?

From the info I gathered so far, I think the oil is becoming aerated from all that sloshing around while on the track and this air in the oil is causing the idle engine noise I am hearing. The noise goes away a few days after the track day. I read that the problem can be solved on some of the other cars by adding an extra 1/2 to 1 quart of oil. So I am thinking of adding some extra oil to the engine for my next track day and see if that eliminates this noise. I also heard that a bit of extra oil may reduce oil starvation issues on the track. Are any of you guys adding extra oil to your R56 engine for track driving? How much extra oil above the full level would be safe for the R56 engine?

 

You could try switching to Redline 5W30 polyol ester synthetic oil to see if that works better for you at the track. I use this all the time and do not have the noise you mention even after running track. This oil seems to have great resistance to breakdown at higher temperatures.

The Mini has a wet sump so there can be oil starvation during heavy cornering. While I do not use extra oil in the crankcase but have heard of some others who do. You can try 1/4 quart first to see if there is a difference. I would not add more than 1/2 quart total.

 

Thanks! I will give Redline 5W30 a try!