"Bolt On" spacers can come loose - not these... they are drilled to match the existing holes with longer bolts. Just torque wheels as usual (78lb) and good to go.

I've used similar designed on Ferrari with lots of high speed with no problem. In addition to proper design, they are light alloy.

Koenig knows what their doing...are you familiar with them? Mentioned in most Lambo history books. Big into R&D and racing for Lambo and Ferrari. Part of the history was doing original roadster conversions for the factory. Take a look at their web...I think it's www.Koenig-specials.com