Originally Posted by GS4TEK
I got the same feed back from other members that are on rca blocks
so I may do the blocks as well.
the 30mm will get less arch gap then 20mm am I right on this?
You would be correct about 30mm having less gap than 20mm. However, if you have an AWD and you want to run 17" wheels you are limited to 20mm. The general report is that if you have RWD then you are limited to 25mm with 17" wheels.
In order to use 30mm blocks you would need to go to 18" wheels full time.