I have done the rear muff delete on several of my benzes including my 91 300d. There is a slight increase in sound, really just a bit of a growl and a slight increase in power and mileage...maybe a mile per gallon or less.

I liked the way it sounded and the bent pipe to replace the stock was about 40 to 60 dollars.

I did i on my 500sec and put the stock muff back on when it sold.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.