Originally Posted by assasinator

woah hold one second here.

straight pipes are loud and the pulses are more pronounced we'll call it a 6 on the loud scale.

stock mufflers are a 1 one the loud scale.

'h' pipes reduce the sound by around 6 dB over open pipe alone. the pulses crash each other and reduce sound.
'h' pipes increase the effective collector size thereby improving torque. open 'h' pipe is a 4 on the loud scale. i have run them open for years without being pulled over.

now and 'x' pipe is a different animal. it does the same thing as an 'h' pipe... it increases collector area and improves torque. now what is different is the pulse waves.

the pulses sonic waves travel out of the exhaust AND back to the headers. an "X" pipe is way louder than any other sound. even with stock mufflers an x pipe without cats in full throttle running is a 3.5. as loud as open 'h' pipes. if you remove the mufflers from an "X" it is unbearably loud. hear it for blocks. people have commented on my old exhaust('x', stock mufflers) as sounding like a race car from inside their car.


'x' pipes and "H" pipes do the same thing for torque, but the "X" does it more efficiently. add 5 or so lb-ft for a 4.6 2v over "H". our cars come factory with "H" pipes and we all trash them and get true "X".


rafael you have to have 1 3/4 or larger headers to make the kind of power you want. 1 5/8 is marginal for N/A 5.4. i am going to fab 1 7/8" x 37" headers for mine. i cannot reach 500hp wothout them.

Originally Posted by f150fella08

H sounds better

Originally Posted by Patman03SprCrw

where does the mallet go?