a car running "R" tires corners much faster ,oil will /can move away from the oil pump pick up in the sump/oil pan........the motor grenades

 

higher lateral G's for sustained long turns can cause problems for any car. So when you put R compound tires on, lower and tune the suspension bad things can happen if you don't address the issue. 1st Gen 987 have a little more of a problem than most and the rod bolts are a weak point on the 1st Gens. 2nd Gen 987 are a little better but I'd be cautious about the above mods on any car without taking measure to protect the flow of oil inside your engine.