Aerodynamics of a bug

[Michael Ghia]

I've read the last aerodynamics post about the Ghia but what about the bug?
I'm still in the process of rebuilding my Oval with Porsche power (3.2 230bhp mid mounted) and as the car will weigh less than the 911 3.2 Carerra, it'll do more than the 150mph top speed capable from the 911.
The last time I ran my bug to 120mph, it was all over the place, the back end was very light.

VW have limited the new Beetle to 145mph, even the RSi with the spoiler which pops up above the rear window. They've also limited it in racing so there is def a problem.

I don't really want to change the body style hugely and a pop spoiler would be good but it looks like it'll have to be a huge wing to make any difference.

Anyone run their bug up to 130mph plus?

MG