who drives a Mercedes-Benz SLK320 2013-01-16
We bought a direct fit after market left side (including the U pipe that joins) cat assembly for a 2001 Merecedes slk 320. At the installation shop when on the rack we saw that the Eastern Cat unit adapts the mercedes 2.5" pipe down to a 2" pipe-wrong size! Seems to me the added back pressure is a bad thing!! This part sold to us may have the brackets that "fit" a Mercedes, but the generic sold has only 2" diameter pipe, not 2.5" as original and as sold by other manufacturers. The flanges are adapted to fit the Mercedes 2.5" pipe down to the 2" Eastern catalytic pipe.
It is well known that smaller exhaust pipe diameters increase back pressure, reduce horsepower, run hotter, and are unacceptable on a performance vehicle. This is particluarly bad if one side is replaced (our case) not both sides, causing an imbalance. We were even told by Midas NOT to put this part on! They were not trying to sell us their parts, they were simply warning us!
Additionally web image shows the left side as ordered as a single pipe assembly, what was sent was 2 pieces requiring connection. Also unacceptable. We are still trying to resolve this. TBD how this comes out. Have not installed, we'll buy a 2.5" pipe!
Word to the wise: Check your pipe diameter!