aharte

Given the available drag information, an SLK55 would need about 380+/-30 hp at the wheels with optimal gearing to reach 200 mph. It seems very unlikely.

SLK55AMG

And the rest!

The SLK55 would need close to 460HP at the flywheel to have 380hp at the wheels (an auto typically loses 18% power between flywheel and driven wheels)

Show me a production road car with less than 450bhp that can hit a genuine 200mph...... I'm still looking but have yet to find many that can do it with less than 500bhp

Shinigami

Let me correct something I said earlier on, the reports of the older SLK reaching a top speed with a renntech pulley upgrade (almost 400hp) was actually 298kph, not 198mph.

That means that the SLK R170 would do 185mph. I think the discussion we had a few years back, was that with a few more transmission related tweaks, the car would break the 300kph limit.

Sorry, my bad for thinking it was mph (it's hard enough for someone who is used to the metric system and living in Europe, to constantly try and switch my little brain to the US measurement methods ).

Therefore, yes, you'd need those +500 ponies to launch the car to 200mph, if the drag coefficient was reasonable (which apparently, it is not in the new SLK. MB made it with a certain design in mind, not necessarily practicality or performance). HOWEVER, the new 7 speed automatic gearbox is apparently a LOT better then most autos have ever been. According to quite a few reports now, the 55 is able to break the 0-60mph limit in 4.2 or 4.3 seconds (4.3 being reports in magazines and websites, 4.2 being a report from several owners that drag raced their car on a track). If it's able to get these numbers (MB's official numbers being 4.9 seconds), it's performing rather well for an autobox, and the amount of HP loss might not be 18% (as was mentioned earlier on, or was it 14%... anyway...).

Maybe an official number would be easier to base someting on? Anybody able to find the RWHP ratings for the 55?

SLK55AMG

0-60mph in 4.2 or 4.3 is quite possible but don't compare those numbers to MBs official figure of 4.9 seconds because that is the 0-62mph time...... those extra 2mph can make all the difference and would easily account for an extra half second.

steve-p

I don't think so. 0.2 seconds more like. It can't possibly take 4.3 seconds to get to 60 and a further 0.6 seconds to get to 62.

SLK55AMG

Maybe not 0.6 but 0.4...... I plotted the trackchallenge figures on a graph..... 62mph is 4.8sec by their test and 60mph plots out at 4.4sec.

Try for yourself if you want...... the figures are here:

http://www.track-challenge.com/main_...4_e.asp?Car=84

All I'm saying is don't compare 0-60mph times with 0-62mph there is a difference.

The difference is even bigger for slower cars...... eg. an Audi TT 225bhp hits 62mph in 6.7 seconds but hits 60mph in 6 seconds dead (again using Track Challenge data)

Teufel

Come on guys! It is not about .2 or .4 or .6 seconds! It is all about TORQUE at low rpm! I love it and it is very addictive! I want more! SL65 more!:v

SLK55AMG

Sorry its just a pet hate of mine...... many people can't seem to understand that 0-60mph is NOT the same as 0-62mph...... most official figures quote the 0-62mph while many magazines (in the US particularly) quote 0-60mph

r i d e r

Do you really need to insult people like that? lol

I'm 17, I bet I'm better looking than you, I have a more expensive car than you on order, ANOTHER car in about the same price range, and my parents didn't buy either of them for me.

Stop being so damn arrogant.

Oh, and I bet my girlfriend is better looking than yours. AND she's not a golddigger.. beat that. Her parents have more money than my family has ever had.