how hard would it be to convert to 4x100? is it possible

 

Yeah, what car? and what year?

Just have to press out the old hub and put eg or ek Hub on it. Bear in mind, we don't know the length of the hub so we wouldn't know if the front brakes will be aligned properly at standard position. You may also need ROH conversion.

Accord -> Heavy as car -> Smaller wheel pcd -> Fail

People usually upgrade to 5 lugs as there are more variety choice in wheels. But if it is about the wheels, they do make extra hole to fit both 114.3 x 4 and 100 x 4

 

sorry its on my 90 accord lx