Ducktail spoiler

72bluNblu said
No gasket. I don’t think they were worried about the paint underneath considering you have to drill like a dozen holes in the trunk lid just to mount it.

I can't see drilling an original trunk for a less than perfect reproduction spoiler. Is there anyway to mount without drilling the holes? Is there enough surface area between the fiberglass and the trunk lid for 3M trim adhesive? I realize that you'll still have dimples...

72bluNblu said
...
I read somewhere that they did actually test the ducktail spoiler on a road course, and that the use of the spoiler resulted in a 10mph increase in the straight away top speed. I’ve never seen any data for that though, so who knows. I don’t remember where I read it at this point either, and honestly a 10mph increase in a straight away seems pretty optimistic. Probably just magazine bench racing.

Nice story but I agree with your incredulity. Unless the spoiler somehow disrupts a major spot of aerodynamic turbulence, top end speed would only be hurt by an effective spoiler. You're exchanging drag for downforce.

So...a really effective spoiler might improve top speed by improving stability enough to affect driver confidence...or perhaps it could allow the driver to get on the throttle sooner from the previous corner? Unlikely though.