hello all, im working with a wheel company to find the correct specs for drilling wheels, and we're confused as to the correct center bore for a new set--because of the "double feature" on the rear hubs. (i think its the rear hubs) if we are working with a blank wheel, what should the center bore measurement be? for front and back? this will be for a square set of wheels. all 15x7 (dont ask) we dont mind having to drill different sizes. thanks for any input.
The thru hole in the wheel is 58mm (and engages the longer front spindle). This is then counterbored by a 67mm diameter maybe ~17? mm deep to engage the feature on the rear hubs. This is all IIRC -- but just measure these (male) diameters on your car (then add a small clearance for the diameters in the wheel). See the front suspension cross-section drawing on page F6 of the 308GT4 WSM. The rear suspension cross-section drawing is on page G2.
