Aerodynamic impact of going topless?

[Gary1M]

I have both the Visium and mesh tops and can confirm the Visium is significantly quieter at freeway speeds. The design of the mesh top results in a gap between the top of the side windows and the sides of mesh top which may contribute to the wind turbulence.

I tend to alternate between those two tops as I greatly prefer the sun protection and cabin openness they provide. I seldom use the cloth or carbon fiber hard tops because, as smac says, it feels too dark and claustrophobic in comparison.

 

[gregd]

I'd highly recommend the Visium top if you can get one. The thing I hate most about having the top on is the cabin feels dark/claustrophobic.

The Visium makes it feel _much_ airier, almost like going topless, but on freeway driving trips it's a godsend for wind/noise.

I haven't got a mesh top, but I'd love to know from those that have both the mesh and Visium how they compare.

Yep, the Visium top was one of the first things I added after getting the Roadster. Love it. The feel isn't the same as taking the top off, rather it has its own charm specifically solving the dark/closed feel of the car when it's dark and gloomy out. But, it's a winter item around here, due to the 100-degree scorching sun summers we have. WAY too much solar gain in the summer sun. So, it's Visium in the winter, and the original cloth top in the summer.

I'm on the wait list for Chris' mesh top, but not expecting anything any time soon. It looks like a perfect solution for the summer. Shade with air flow. The Visium top, by the way, seems to me to be noisier than the cloth top, though not so much that I wouldn't use it. I think it's due to the way it (doesn't) seal around the edges. I saw one thread where putting a strip of black electrical tape over the joints helped in that regard, but I haven't tried it due to the visual impact and what it might do to the paint. Also I think the hard surface, vs the soft cloth, reflects noise inside the cabin instead of absorbing it.

 

[smac]

@gregd I think the originator of the electrical tape fix was a fellow Brit of mine Mark Sanders. I've seen it in person, and visually it looks pretty neat. I know he's been running it for a while and, AFAIK, no paint issues. I guess the bigger problem is the time investment making a neat job vs number of times you take it on and off. At least here where 100 degree days are a rarity, the Visium is almost a year round solution. The warmest I've tested mine to is 95f, and in fairness the A/C system was still able to keep up.

I completely understand what you are saying re the noise levels, the Visium definitely makes the interior acoustically brighter as well as optically

Last year I did some European touring (avg. 400 miles per day), and was in two minds as to which top to take. In the end I took the soft top option and glad I did, it was nice driving in the mountains with the roof off, but was really glad of the A/C on the hot days.

 

[Tesla 940]

Several years ago I made numerous identical 140 mile round trips - some with the soft top on and some without. At 70mph the top on reduced consumption by 5% - 7%. The mesh top was in between the two.

 

[gregd]

Several years ago I made numerous identical 140 mile round trips - some with the soft top on and some without. At 70mph the top on reduced consumption by 5% - 7%. The mesh top was in between the two.

Perfect. Good info, thanks!

 

[Roadster]

Would it matter if the windows were up or down, with the top off?

@Tesla 940, side windows up or down?

 

[Tesla 940]

With the top off the windows were down. With top on the windows were up.

 

[thefortunes]

With the top off the windows were down. With top on the windows were up.

Windows down may have a larger impact on range than the top being off (and also may be why I don't see a reduction when I run topless - on the highway my windows are typically up even if the top is off).