I would ask riss racing. But I would probably not do it. If the ram intake works as intended (a not significant if since the airflow around a vehicle may not result in a higher pressure area at speed at the location of the riss intake) it will have the same effect as a mild amount of supercharging (or turbo charging). That gives you more power but also more tendency towards detonation. The BMW engines are already pretty high compression so adding to it with this method of forced induction, if it works, could get you high enough to cause damage. Doesn't seem worth the risk to me. There is also a chance that the pressure is higher at the location of the BMW intake than with the Riss racing intake. In that case you would not damage anything but you would loose power.
On the other hand, if the supplier has tested the product and can show evidence of both a benefit and lack of damage, that would be different. If you have to guess, I wouldn't.
128i Convertible, MT, Alpine White, Black Top, Taupe Leatherette, Walnut, Sport
Ordered 5/22/09, Completed 6/4/09, At Port 6/9/09, On the Georgia Highway 6/13/09, Ship Arrived Charleston 6/24/09 at 10pm, PCD 7/21/09