Top-down motoring

[Charles Morgan]

There were many things I enjoyed about my Boxsters, but the ability to open at close the hood at up to 30mph was tremendously useful. Again I normally ran around with the hood down, but on one trip in Germany near Stuttgart, it was 38 C on the thermometer, and at 155mph it was like sitting in a superheated hairdryer. With the hood up, the climate control was able to bring the temperature down to a much more serene level. I was also able to hit an indicated 164mph, the highest I have or am ever likely to achieve(d).

 

[MOCAŠ]

The general rule with Angie's SLK is No Rain = No Roof, but the exceptions are:

1. If we need the additional boot space (very rare)
2. If it's seriously hot, i.e. 30c+ then having the roof up and the A/C on for a while can provide welcome respite
3. When there's strong sun and I've forgotten the sun block
4. On very long motorway hauls - i.e. > 4hrs - as the additional wind noise increases fatigue

Like I say, on very long journeys at high speeds the wind noise certainly increases fatigue. Also, I've found that at an 80mph cruise an SLK350 does around 1.5 to 2.0 mpg worse with the roof down compared to with it up.

Sounds like four very sound reasons for keeping the roof up occasionally.

Can't say I've ever spent 4 hours on a motorway in one stretch, but I recall a couple of longish (for me), mainly-motorway drives that were top-down all the way. One was coming back from a break in the Lake District in my X1/9 on beautifully sunny afternoon/evening; the other was in my R170, driving home in the small hours of a balmy midsummer's night, after visiting friends in Chesterfield. It's on days like these that I can't ever imagine being without an open-top car.

I've often wondered (but not really cared) about the effect driving with the top down was having on fuel economy. Is it really as little as 2mpg or less? I'd imagined it would be around 5mpg at least, given the extra drag, but even that would be a cheap price to pay for the experience.

 

[MOCAŠ]

There were many things I enjoyed about my Boxsters, but the ability to open at close the hood at up to 30mph was tremendously useful.

On that note, has anyone here had a SmartTop module fitted? I believe they're available for both series of SLK, and allow the roof to be operated at up to about 35mph (or remotely, without the hassle of the factory-fitted remote operation).

 

[Noodle-Pulp]

On that note, has anyone here had a SmartTop module fitted? I believe they're available for both series of SLK, and allow the roof to be operated at up to about 35mph (or remotely, without the hassle of the factory-fitted remote operation).

I thought these were illegal in the UK.. wonder where I got that from...

 

[gary350]

My rules with my 2 slks were dry and sunny at 25 degrees roof down above 26 degrees roof up, sorry boys I buck the trend, just too much light, air, sun and noise.

 

[BTB 500]

I thought these were illegal in the UK.. wonder where I got that from...

I doubt it ... many newer cars allow you to operate the hood on the move.

 

[bpsorrel]

I can raise or lower mine at up to 20 mph. If it's dry and above zero, the roof comes down!