Fabspeed Motorsports just completed an installation of Kleemann's Sport headers and 200 cell sportcats on this 2005 Mercedes Benz CLK500AMG. The headers are constructed from T304 stainless steel, C.N.C. mandrel bent and utilize a 4-into-1 high velocity merge collector for optimum exhaust flow. We replaced the stock catalytic converters for a less restrictive 200 cell per square inch sport catalyst to aid in performance and improve low end power. The CLK500 AMG makes 312HP/363ft-lbs tq stock but with the Sport headers, 200 cell sportcats, and BMC air filters, power improved to 336HP/387ft-lbs tq. Kleemann has sport headers available for all AMG Mercedes Benz vehicles including the 430/500/55/and 63 models and Fabspeed stocks BMC F1 performance air filters for these vehicles as well. Visit FABSPEED: Mercedes Benz Kleemann for more information on Kleemann products for your Mercedes Benz. If you have any questions or inquiries regarding Kleemann products, email Jeremy@fabspeed.com or call Fabspeed direct @ 215-646-4945.

Mercedes Benz CLK500AMG on Fabspeed's AWD Dynojet
Kleemann Headers and Sportcats Explanation Video
Kleemann Headers vs. Stock Photos

 

Would have been interesting to see the dyno run with stock manifolds, filters - changing only the cats.

I think you'd have gotten the same numbers.

 

20HP/20ft-lbs tq from just catalytic converters alone would be a good power increase but is very unlikely especially while maintaining the stock manifolds. The Kleemann headers really make the difference in terms of power/sound on all V8 Mercedes Benz vehicles through the use of larger diameter pipes and a 4-into-1 high velocity merge collector.
The stock manifolds have a 1.34"/34mm inlet diameter and a 1.59"/40mm outlet diameter while the Kleemann headers have a 1.62"/41mm inlet diameter and 2.57"/65mm outlet diameter.

 

Yes I got to vouch the Kleemann headers are substantially larger than the oem headers on my SLK55, I am really sad that AMG really downtuned the 5.4 M113 on the SLK,C55, CLK55's it really can be unleashed with a tune,filters, headers and resonator removal.

 

I don't mean my post to sound anti-K-headers, they've always shown good power compared to stock - but the 2 n/a 55 Klee-cars we've had here had the headers and no cats, and weren't making that much power (obviously: stock cats!). I'd be interested in knowing how much of the gains are cats is all.

 

The power increase is a combination of the Kleemann headers and downpipes with or without cats. Did you dyno the n/a 55 kleemann cars to see what the power difference was. If you do have them please post them because I have been installing and dynoing these cars for a long time and always see at least a 20 -25 wheel hp gain. On the supercharged cars I have seen 40hp gain.