does the drag equate to a couple mpg?

 

One or two mph at highway speeds. I would assume the loss would be significantly higher as the speeds increase past that. Top down = terribly innefficient.

 

If I had to guess, I'd say about 2 MPG.

As an aside... even when gas hits $4/gallon, it will only cost you a couple pennies per mile to drive top down

 

Just made a trip to San Diego from SF Bay Area early this month. On the way down to SD, the top was up the entire time. We averaged around 85mph while on the road and got 28.xx mpg. On the trip back home, the top was down the majority of the time and we averaged around 88mph while on the road. Heading North on 5 always means heading into a bit of a prevailing wind so that and the speed also was a factor, but we averaged 22.xx mpg. I would assume that at equal speeds we would have been closer in mpg average. However, I am certain that top down does affect mpg average by around 10% +/- depending on average speed.

 

i dont know how you guys drive that fast at a constant rate in this car. fastest i feel comfortable wind wise is 73 mph.

 

top down in S2k is best in a mild sunny day without any wind, my own experience seems indicate top down cost around -3 miles per gallon.

 

"See this thing my foot is on? It's called an accelerator. When you push down on it, it sends more gas to the engine. The whole car just takes right off. And see this thing? This steers it." -- Steven Wright

I've always wanted to use that quote.

 

The tests I've done are VERY inconsistent, but the results were ALWAYS consistent.

Top up = 24-25MPG
Top down = 21-23MPG

Take it w/ a grain of salt..

 

... provided you aren't in a tunnel or driving in the lower deck of a bridge/highway -- the noise becomes almost unbearable.

Otherwise ... it's fine

 

Offtopic, however KS, check your PM.