Vpatriota

As the title goes, I'd like to know how much whp the SLK 55 R171 actually has. I'd put mine on the dyno, but I don't have free time soon enough. I know it has around 355hp, but what about the real power on the rear wheels? Anyone knows this? Thanks.

Steve_k_550

Apparently these motors are very hard to make power on , Sonny from autowerks in Sydney dyno'd one after headers , tune and custom built dual 2.5" exhaust which pulled around 320 whp

In stock form id say 260-280whp

Vpatriota

I thought so. There's the possibility of adding a Kleemann Supercharger, that goes around 12k euros, to get 400whp or so. Pretty expensive for so little gain. Thanks mate.

Vpatriota

Second thought, you said 260-280whp, but MB states 355hp, less 15-20% would give me around 300whp.. 280 is not very good :/.. But that torque tho.

Steve_k_550

Just remember a dyno is simply a tuning tool I wouldn't get caught up in trying to convert rwhp to crank output

The same slk55 on one dyno will give one result then another result on another dyno if you want to see how much power your putting out at the motor the best way is to take it to the drag strip and work off your et and mass of the vehicle

Nevertheless don't be concerned if your only putting out 260-280whp it's a very fast car and as tested in standard form can cover the 1/4 mile in 12.7 @111mph

Vpatriota

Yeah yeah, I'm pretty confident about this "girlish roadster", specially when some Boxster S's and F Type's (V6) lined up with me the other day. Everybody gets impressed. I was just kinda disapointed with the numbers, althought the car feels great. It's a lot of torque, at least for my humble standards. I'll try it out on a dyno someday to get my "whp" score. Will let you know. Thanks man! Cheers from Brazil.

cadeca

I dynoed mine at 270whp and 285 ft/lb torque when it was stock and 320whp and 325 ft/lb after MBH long tube headers and a Kleemann tune. Both runs on CA 91 octane unleaded and on the same Mustang dyno (not on the same day). It is a quick car and is a lot of fun for track days as well!

cadeca

Might want to check your numbers...with 20% power train loss, 280 comes out to 350. Real test is to check your acceleration. If you're running the quarter mile in significantly more than 13s, you have a performance issue.

Steve_k_550

A 50whp gain on a n/a vehicle is insane it would be one seriously quick slk55

Steve_k_550

Just remember some dyno's are more generous than others I've had my m273 e550 dynoed at 300whp on one dyno and 335whp on another

Vpatriota

355hp - 15% = 301hp.

Your numbers are really impressive, with that Kleemann tune. I believe that would be available only in the US? Never heard of someone remaping a 55 around here.. Will check their website for sure.

cadeca

Sent you a PM response. Kleemann is based in Denmark and should be available in Brazil. I think the headers made a bigger difference than the tune. I noticed they didn't have the AMG 55 NA in the catalog portion of their website, but I know it is available. Recommend contacting them directly to ensure you get what you need. Best wishes!

cadeca

Ahh, I see what you mean now. I thought you were stating that 260- 280whp was only 300hp at the crank...

Vpatriota

Just saw it! And answered. Too complicated, and too expensive, for now. I'll stick on racing Boxsters and Jag's..