[Driver]

Originally Posted by LSxJunkie

Depends on the warranty issue. Your radio is eating CDs? You're good. Stitching on the seats comes apart? Covered, no problem. Headlights on the fritz? Bring it in. Passenger window will no longer auto-up? Golden.

You oval out a lower control arm joint because you're running R-Comps and the link was never designed for that much lateral stress, that's a different story. That's probably not going to happen until someone builds a 500whp track monster, but it's just an example. Some street stuff is just not designed for racing.

E36 M3s would develop stress cracks in the rear subframes from stiffer suspension because all of that impact was transferred to the metal instead of being soaked up by the shocks and springs.

C6 Z06s suffered from oil starvation (and blew up nice, expensive LS7s) on long sweeping left handers with R-Comps because the car was never tested with sticky tires (even though the goddamned dry sump was specifically designed to avoid this problem).

There are all sorts fun weaknesses that wringing a car out beyond street use will expose. It is honestly unreasonable to ask a manufacturer to warranty all of these issues when the manufacturer is in the business of selling road cars, not race cars. If you have a failure and your car is completely, 100% bone stock, it should be warrantied because this is how they are designed and tested. However, once you start changing things, the argument against coverage becomes more and more compelling. This is why some (very rare) companies will sell you a body in white without a VIN or warranty if you really want to go racing.

best answer yet and probably to come.