I have used two pair of Flowmaster Super HP-2 mufflers on my -63. The long ones in normal position and the short ones as resonators, further back in front of the rear axle. The annoying exhaust drone went comletely away and gave a slighly more mellow exhaust tone, without loosing the engines caracteristics. Driving long distances is now a real pleasure! From the outside, the car still sounds like it should, with the real sound of the V8. You can get these mufflers in either 409S stainless steel case or 304S stainless steel and in the sizes 2.00 inch, 2.25 inch and 2.50 inch. I have a Silvertone exhaust system from Don Simmons (in 409S stainless steel), but choose my own mufflers, and it fits very well together and in the frame.
Marcus A
Sweden
