Exhaust time w/ the EVO X

So I have been given a muffler to try out from Flowmaster called the Hushpower dBX. This muffler is different in design compared to allot of mufflers out in the market today. Flowmaster has been around for 25years and has dominated the Muscle car market and never really struck and accord in the import market. So what sets this part apart from other mufflers, is that this muffler has a perforated cone shape tube. When the hot exhaust gas enter into the muffler and expands, the angle (specifically calculated) on the cone disrupts the turbulent gases to control it.

A picture below shows the inside of the muffler and what I'm talking about


So the project started off w/ some building materials: a few mandrel bends, stainless steel 3.00" flanges, some hangers and a 4.00" single wall tip.


So I tried to keep the bends as minimal as possible to not cause much disruption, but honestly we are probably talking only 0.5-1hp loss if I were to use 90deg bends, but luckily I only had 15deg bends to work w/.

Below is a pic of the set up. In the picture I decided not to use a resonator to quite down the sound alittle more.





So I finished mocking up the exhaust and drove it home. The sound of the exhaust is not loud to my ears, although I still have the stock catalytic converter and the stock down pipe which allot of people w/ EVOs seem to replace it w/ higher flowing parts. But the sound is very mellow, the cool part of the muffler is that when you whomp on the throttle the sound it cut where you can barely hear it. It definitely lives up to its name.



To optimize my exhaust system I decided to make this Hushpower more like Stealthpower. So I picked up some VHT Flameproof header paint at a local autoparts store, not only will this make my exhaust more sleeper, but the coating will also help keep the heat within the exhaust system. Keeping the heat within the exhaust helps keep the velocity of the exhaust pulses. I like to used lava as a good example of how keeping the heat will keep the velocity up. When lava is exposed it will travel slowly, but keep lava in a insulated tube it will travel quickly. A simple formula for ideal gas laws pV=nRT. In this equation as Temperature is up so too is the Volume.


The only down side to this paint is that it take 7 days to cure. I also installed a resonator also.

The final complete exhaust system