They supply spec tires for a given series. Even then once the teams have the tires...who knows what happens
YYYYaaaUUUPPP –
Unfortunately nothing has changed -
Just like a sealed engine - Kinda sucks. When the manufacturer supplies you with the marking paint so you are able to open a (QUOTE) sealed engine and refine it (Valve seat work ECT.) and visual / tear down inspection shows nothing because of the skill level of the parties involved, it’s a tad unfair to the average competitor - Been there and seen that. One reason I was disappointed in certain sanctioned racing. There will always be flat out cheaters when pride and $$$ is involved. I’m not talking about improvising or rule interpretation - I admit to that and am comfortable with it but just flat out cheating.
The newer HP per weight rules are a huge step forward.