But they would be ungodly heavy. My 15" steel racing rims are 22#. There are a number of 17" aluminum rims that are around the 22-25# range. 18" aluminum is around 25-28#. 17 to 18" steel rims are going to be in the range of 30-35# each. that's a 60+% increase in wheel weight, or enough to be noticeable when driving. You will need to put your shocks on a regular replacement schedule with that much mass.
