Originally Posted by ben@tirerack
275/30R20 on the back would reduce the height and width a little bit, but the bigger issue here is the 20" wheels. Before you worry about the effect of a fraction of an inch diameter on acceleration, worry about the weight and rotational inertia of your 20's.
Thanks Ben for the info! The wheels should weigh less than OEM and I'm looking into titanium fasteners to reduce weight at the rim (where it matters most).