UPDATE
I have spoken to several GT5 interns regarding the cars setup, and there is no 100% way to see if anyone is cheating.
Tyres and Break settings : Tyre and Break settings can be seen in replay mode with FULL HUD and the RA Menu turned on
As to engine tune, body tune (decreasing the cars weight) there is still no way to prove this.
I dont know why, but in GT4 we were able to use the arcade cars as completely stock and not modifying them!
As to this point i am not 100% sure if this competition can be continued, since the price that can be won has a certain $ value, perhaps I and all the competitors will have to wait until PD releases the TIME TRIAL SETUP (as we had in GT5P)
I will keep everyone up to date as soon as i know more info!!!
I just would like to say, that this competition will be run eventually 100% sure and the winner will get his Kart Racing wheel, signed by me, 100% sure!
Thanks
Chris