DIFFERENCE BETWEEN THE TWO ON THE TRACK OR ON THE STREETS! WHAT WE FOUND IS THAT ALUMINUM IS HARD TO DRIVE ON THE STREETS AND CAN BE FRUSTRATING ON THE DRAGS. ON ROAD RACING IT IS ABSOLUTELY GREAT! Obtw, I get numerous requests for technical advice and if interested, tex me @ 626 203 2712. Half hour to 1 hour+ rates are available. Most calls go over as posted and it is ok. US Pacific time zone.