Originally Posted by
Oconnom
Hi,
My exhaust man says 'X' joint not required on my car. Says 'X' joints are for cars that have completely separate systems for each bank of a V engine, enables the two banks to be connected.
My stock system is quite simple - down pipes from each primary cat, along to the secondary cats and then out into a 'Y' joint, then single pipe straight into the muffler. No resonator, is the resonator a US requirement?
Mick
'06 Aero Blue Coupe
UberMapped
Find another exhaust guy. Your's is a putts. Our "V" engine has 2 - 3cylinder banks. Hence the "2" downpipes. Only the SRTs have a resonator. Removing the rear cats and replacing with straight pipes will give you one heck of a drone inside the cabin. The "X" pipe eliminates that drone and assist in the flow and scavenging effect which provides more linear flow and thus more horsepower and fuel savings to boot. The X pipe is just an improved form of the H pipe which was conceived in the 60s by the mfg to cut down on exhaust noise inside the cabins from the larger V8s they were installing.
I'm running without a muffler and have no problem hearing my music or talking to passenger. When I get on it all noise is heard at the rear of the car. Many who have done the Ansa or Magnaflow systems and left all else intact complain of the loud drone produced around 50-60 mph. The "X" pipe eliminates that!
Why X over H?
It has been proven time and again that the X-pipe design is more efficient than the H-pipe. Various tests have shown that for multiple cylinder engines the X-pipe outperforms H-pipe exhaust systems, especially as rpm increases, providing both better torque and power. Unified exhaust pipes work most efficiently with multiple cylinders because of the scavenging effect. With exhaust X-pipes the almost seamless connection between the two exhaust pipes allows sequential firing cylinders to salvage any spent exhaust gases from the combustion chamber more efficiently and creates more room in the cylinder for a fresh intake of undiluted fuel and air. When you have two exhaust pipes, as the velocity in one header tube increases, the pressure in the adjacent tube is lowered causing the exhaust to be sucked out of that cylinder. X-pipes are simply better at doing the job, especially at higher speeds.