Attention: TDR Forum Junkies This mod will cost you less than $2. 00, and in my opinion, far better than what is out on the market.
All you need is a stick of 4 inch irrigation piping. Follow the Hoot method in opening up the air silencer, however, you will have to enlarge each end of the unit to allow the 4 inch piping to fit snug. Use a carbide bit on a high speed grinder, and try to get the opening as round as possible. The black plastic is pretty tough to cut, so go slowly. Cut the pipe about 1/4 longer than the overall length of the air silencer so 1/8 sticks out at each end. Here are the benefits:
1. Stealthy, can't be detected by dealer
2. Flows better than if no piping inserted (my flow bench showed a 20% improvement over an empty can. Too much turbulence going fro 4 inch, to 5 inch, then abruptly back to 4 inch.
3. Uses the factory elbows which in my opinion are superior to anything available on the market. Plus, they allow some degree of flexing which is required since the motor torques over depending on acceleration and deceleration. The torque tubes on the market have pretty rigid couplings.
4. Bonus, if you drill a small hole at one end of the air tube, and flow some expanding insulation into the void, the unit won't pass heat into the air flow, unlike the aluminum or thin plastic units on the market.
I also found a small increase in flow removing the baffles on the lower elbow too. My guess is the baffles were inserted to eliminate air vortexing to reduce any noise.
Good luck!
All you need is a stick of 4 inch irrigation piping. Follow the Hoot method in opening up the air silencer, however, you will have to enlarge each end of the unit to allow the 4 inch piping to fit snug. Use a carbide bit on a high speed grinder, and try to get the opening as round as possible. The black plastic is pretty tough to cut, so go slowly. Cut the pipe about 1/4 longer than the overall length of the air silencer so 1/8 sticks out at each end. Here are the benefits:
1. Stealthy, can't be detected by dealer
2. Flows better than if no piping inserted (my flow bench showed a 20% improvement over an empty can. Too much turbulence going fro 4 inch, to 5 inch, then abruptly back to 4 inch.
3. Uses the factory elbows which in my opinion are superior to anything available on the market. Plus, they allow some degree of flexing which is required since the motor torques over depending on acceleration and deceleration. The torque tubes on the market have pretty rigid couplings.
4. Bonus, if you drill a small hole at one end of the air tube, and flow some expanding insulation into the void, the unit won't pass heat into the air flow, unlike the aluminum or thin plastic units on the market.
I also found a small increase in flow removing the baffles on the lower elbow too. My guess is the baffles were inserted to eliminate air vortexing to reduce any noise.
Good luck!
