Dale Gribble

A couple of questions crossed my mind and after a fair bit of searching and comming up empty handing i figured i'd ask over here.

When dealing with a center lock assembly, as far as rim interchangability goes, is it all pretty generic? Can a BBS wheel fit with another assembly and vice versa? To What degree is this possible?

And also, what is the formula used to determin the tightening torque of the center lock pinbolt (the big one that slips over the driveshaft) and the outter nut (used to hold the wheel in place). My initial thought is that tightening torque must be greater than the torque output of the engine so that the nuts dont break loose, is this correct?

Geoffrey

The centering ring is most likely unique for a manufacturer. The BBS centering ring will not fit on a Fikse and vise versa, same with the speedlines found on a 993 Cup. However, there may be manufacturers out there that design theirs to work with the BBS style.

The centerlock pinbolt has the same torque as a standard driveshaft nut on the street car.

Dale Gribble

Thanks Geoffrey,

so there would be no need to adjust torquing specs on any of the parts if a supercharger was added to up power i'm assuming.

Geoffrey

I have no idea on that. I think the torque value is derived by the proper amount of stretch the bolt will incur. I would not torque it more than what the factory specifications are. I know of a few high HP turbo cars running center lock wheels with no issues with them comming loose.

I have seen broken stub axles and with a centerlock wheel, that means the wheel comes completely off - BAD! I would think that if you overtorque the axle by installing the center lock screw it will stretch the stub axle more than it is designed for and it will fatigue and break off. You wouldn't want that to happen, especially at Mosport...say turn 2 or 4?

Dale Gribble

Good point, that would be a most unpleasant occurance