need to drill on center only. side no need to drill. this is white room bar is not orange. this picture is taken from a sepang track trainer evo 6. he said that if u like to play corner room bar is a necessary if not the car chassis will crack. he told me that the 3 points is stronger and more reliable than the 2 points bar. he suggest us to use this room bar. is up to your choice.
see his car with full bucket seat. he is the ulu yam king also
bro - evo chassis already strong lah... it wont crack unless you kaki track 24x7, 265 days a year for non-stop 5 years as per say!!
putting bar at only 1 section will severely fatigue the specific point of the car. it's all rollcage or no go if it's for full spec track car..
anyway whom am i to say, i'm not ulu yam king ;) . wouldn't mind to meet the ulu yam queen though...
eh DDgreystar, i tot you ulu yam king? when did you own evo6 pulak?? hahahaha