if will change to my new Fenton headers next weekend but i don't know whats the best diameter of exhaust system 2", 2.5" or 3" ??? Volker
What size are the header outlets? 2" should be more than enough for that engine. You might even need to go smaller when running 2 pipes to keep up enough backpressure, but I must deffer to the old masters on this one.
Dual Exhaust Just match the inner diameter of the Fenton's outlet . You'll be wise to add a crossover to retain the power output as a true split exhaust reduces power until the engine reaches 3,000 RPM or so ~ they're for Racing not puttering 'round town . Of course , if you just want that nasty blatting sound that upsets the Police & neighbors whilst reducing power , no crossover is necessary . Be aware the Fentons will need some creative washers to prevent leaks at the head gasketing area . Anyway you do it , mufflers are not necessary on these engines as they're very softly cammed . A 40" or longer glass pack , if you can find it , makes a very pleasing , deep , mellow , athorative rumble . I just dispense with mufflers altogether in my Babbit pounders and don't get tickets , not even when hauling loads uphill through Bel Air or Beverly Hills .
