18s can provide better adhesion, due to the decreased sidewall flex. however, that can also lead to snap oversteer as well as understeer.
also, unless you choose carefully, the location of the mass of an 18 can dramatically decrease your acceleration and braking capabilities. however, if you choose wisely, it can put more of the mass toward the hub, and actually improve things.
18's, and the tires that go on them, can also increase loads on the suspension components, which can mean higher maintenance costs.
but, as mentioned, if you aren't actually racing, it's a more expensive proposition, to no point, so i agree, 17s would be just fine for any DE car, and in fact i think would be better, if you went to a lower profile that stock 17, thereby reducing the outside diameter, lowering the final gear ratio, and improving acceleration, albeit at a cost of top speed (which you would never use at a DE anyway).
were i to build a DE car, it would run 17 x 9 all around, with the same offset and same size tire all around. that way i could resolve the understeer issues and gain the ability to rotate tires, thereby increasing the number of events per dollar.
94 Midnight Metallic Blue Cab Porsche 968 w/deviating cashmere/black interior and WAY too many mods to list - thanks to eric for creating
www.968forums.com
"It isn't nearly as expensive to do it right as it is to do it wrong."
