Is a well upgraded Arial Atom 3.5 fast enough to reach the Arial Atom V8 showcase or do I need to upgrade a Caterham 7 to win the races approaching the Arial Atom V8 showcase?  I've already got the Arial Atom 3.5 upgraded quite a bit and don't want to spend money/GC on the Caterham unless I have to.  They seem fairly comparable, but maybe the Caterham gets a lot faster with upgrades.  Thanks.

Jon