Check out this Superformance Cobra that we just finished installing a fresh set of our RAD S5, 18" in Autobahn Satin Black whole wheel, wrapped on BFGoodrich Rival's.
Sizes are: 10.0X18, 275/35-18 and 12.0X18, 335/30-18.
That should be enough rubber for this little monster.
BTW...this is a very unique Cobra as it has a Lingenfelter LS3 with a trumpet, Kinsler style injection system. See her at the SEMA show in the Meguiars booth.