I know it sounds odd but I think it is how these cars are designed to break from the get go (overdriven on asphalt) and not designed for dirt. My Sprint was the same... grade 8 bolts all the way through it and no issues. Of coarse it had bigger bolts than 1/2 inch. Grade 8 bolts always bust off on my Legend on the panhard bar if I hook a rut or tap someone with the right rear. Never busted a 5 on there unless I flipped over a few times. When off-setting the front end as well as getting more suspention drop on a Legend front end, I constantly snapped 8's on the front lower rear control arm pivot points. I bent 5's since, but never sheered one off unless I endo'd or rolled one violently.
Another issue I had with grade 8 bolts is if I had someone helping check over my car between races. They would check if the bolts were snug by pulling on them a little each time with a wrench.. repeated tightening this way put tention on the carbon steel and made them week. The grade 5 bolts would streatch and give a lil not becoming brittle. The only place I ran a grade 8 bolt was on the upper control arm pinch clamp. That clevis end would snap before the bolt would, no matter what bolt you stuck through that hole.
Another aspect I looked at is if we snapped a grade 5 (seldom), it was easier to drill and extract than a grade 8 is to drill and remove when you have to do it in the pits. Lol, honestly I don't care if racers use 8 or 5's. I prefer 5's and have had better luck with them on the Legends chassis over the years.
~ Gimpster ~
