Straight Pipe Noise

[JBoone]

I HAVE A 50/50 EXHAUST SYSTEM. FIRST 50% 3" AND THE SECOND 50% 4". I LIKE THE SYSTEM, BUT I HAVE A DRONE NOISE IN THE CAB WHEN ACCELERATING FOR JUST A FEW SECONDS. I WOULD LIKE TO KEEP THE SYSTEM AND LOSE THE DRONE. TAILPIPE EXTENDS ABOUT 2" OUT FROM BODY BEHIND REAR WHEEL. ANY SUGESTIONS.

 

[Steve Campbell]

Put a resonator (should be lots of them off of 24 valves for cheap) or muffler at the 50/50 point in the system.

 

[KB0OU]

INSULATE

Put some insulation on the back wall of the cab.

 

[Koa Man]

Some members have clamped or welded a piece of angle iron to the pipe to change the sound wave and say that has helped. I would use hose clamps to attach the angle iron first, then if it really does help, have the iron brazed or welded on.

 

[wtrenholm]

Here's another thing that may work. Under a lot of mid 80's GM front wheel drive cars there are hockey puck looking units that are mounted to the exhaust and on the engine cradle. Some were screwed on the exposed exhaust clamp threads and it's purpose in life was to dampen unwanted vibration which is basically the drone from exhaust pulsations. Might work or might not, but would be a cheap fix and would be easily movable on the exhaust system for trying different results.



HTH

Wayne