What do you mean by top speed? For drag racing? or racing? if drag then just remove wing angles from your setup. If racing then, you can't make a setup fast on straights and slow in the corners but you have to compramise, you can't have both, just get one from www.setupgrid.net and stick to it if you can.
wel its one for on the blackwood circuit it must gear up fast so i get fast my speeds cause when i race other cars just get me in cause they accurate much faster ...