[DanEC]

C2 Corvettes have also gotten along fine with 5-pin KO wheels for decades. I've never heard of a pin failure on one of them either and that's considering they weigh 500 - 700 lbs more than a Cobra and owners have been driving them hard with built motors all these years. And 4000 lb musclecars with modern built engines get along fine with 5-stud wheels still. Blow an axle or ring gear once in awhile, yes - but shearing wheel lugs is usually only an issue with over-torqued lug nuts and fractured lug nut studs.