well i got a 2004 supercrew Lariat 4x4 with the 5.4 and i had a SI/DO flowmaster 40 series with turn downs and it was too quiet so i decided to cut the muffler off and run true dual straights with 4'' tips with the 4 original cats and stock manifolds. well its really quiet for striaghts and it sounds really good but ive lost some power and the pipes have different pressures along with different sounds (weird enough one pipe is deeper and lounder). i want to buy two flowmaster super 44's and keep true duals but my question is that if i buy an h-pipe and put dual flows on my truck, will my pressure balance out and will i get my power and gas mileage back? or should i put a dual in dual out muffler? I NEED HELP!!!!

 

Yes if you put a crossover pipe in it will equal out the exhaust gases.On my 05 ,I have true duals with flow original 40's and no equalizer pipe and my driverside is louder and deepeer then the passenger side.Once tax money gets here I am going to put high flows in and possibly an H pipe to equal them out.Even with my system now,I didn't notice any drop in power or gas milage but i did on my 99 with 5.4 and true dual straights so i know what you mean.Mufflers will help you get your power and milage back but it will also make it quieter.These cats suck on these trucks,way to quiet.If you do a crossover pipe a X pipe will gain the most horsepower but also quiet it down more while a H pipe will make it deeper and not mellow it out as much Thats why I am planning an H pipe.

 

Forgot to add with my current setup,true duals with 40's ,I can now floor it from a dead stop and light the tires up posi,and got a nice mid range increase also.Now if it was only louder.

 

How do you figure that?

- NCSU

 

h's are known for sound over the x's as the x's are better for scavenging exhaust gases while balancing the flow as well as the sound-in the process quieting things a tad

 

X2.

H's have a louder, more aggressive sound.

X's will give better power with a milder tone.

Any form of a crossover is going to hush up the exhaust some...

 

I did a lot of research on them.H pipe is old school technology and X pipe is more of a newer version.I'm not into it for every last bit of power increase ,just sound.

 

I would just put a crossover on and leave it with no mufflers that should fix your problems

 

From all the Mustangs I have heard the x is way louder than the H setups.

 

thanks a lot for yalls info but im gunna go with the xpipe with dual 44's and hopefully some high flow cats soon, but no joke these stock cats are quiet as hell!