OldCarBum

I've built several cars over the years and have always had true dual exhaust and headers.
I know the new hype is adding an X pipe for performance and some people say it helps to reduce exhaust drone.
I really hate the sound from the new Mustangs, Challengers, and other cars that are louder and just slightly deeper than a Honda civic with a straight pipe.
I'm sure you all know the sound I'm speaking of.
My question is:
What effect, on the sound, will an X pipe have on my 3" true dual exhaust system with headers?
I'm talking about idle, cruising down the highway and when I decide to get into the throttle.
If you have an example, please share.

The13Bats

Im not a fan of the pseudo muscle car siund on the new ones and i dont like cars that one has to look at the tach to know the are running.

From my experences a cross over pipe always tames the sound some cases more than others,
Im also of the mindset its one of those things needed by guys hunting that 10th of a sec in the 1320

Strokemyaxe

gkull

Combing the two pipes with an H pipe or an X pipe basically doubles the frequency and cancels out the deep base sound

also to a trained ear you can stand next to road racing track and shut your eyes and be able to pick out different engine manufacturers because of the firing order distinctive sound

so I have a 4/7 firing order swap cam in my 434 people at the track commenton how nice it sounds. That is actually making it like the same firing order as a Ford Motor. The modern vettes even have a different firing order and Mustangs have altered the degrees of the crank throws.

I have 3 inch pipes and a H pipe my present 396 sounds great

cv67

The X helps reduce high pitch frequencies, drone or volume didnt change.Agree its a trend like when the H was a big deal in the 90s.
Not a fan of how newer cars sound either, meaning they seem to mimic an AMG/Euro car. Dig duals with no crossover esp if it has a cam, to each their own.
The different firing order is supposed to be a little easier on the crank (imo doesnt matter in the grand scheme of things). Make it yours and enjoy

69427

A trend to some, productive physics-in-action to us engineers.

69427

I'm not following why the 4/7 swap would sound different.

I'm running a 3" system and H pipe in mine also.

gkull

It sounds like the ford firing order

cv67

at cruise/wot it sounds more like an 80s 5.0 mustang note...more smooth like, same with idle you lose a little of the crackly valvey sound. The pitch changes some
No crossover has more of a gutsy hot rod tone to it
your X will still have some rasp to it on wot just not as loud thats all.

69427

Okay, but the mufflers don't see any difference in pulses coming out of the header collectors. The exhaust pulses are LRRLRLLR for both systems.

jb78L-82

I don't have an X or H pipe on my 78 L-82 355, just 2.5 inch duals with 1 3/4 LTh and it has a nice sound at mid to high RPM. I do have a 94 5.0 Mustang GT that went from the ford H pipe with ford mufflers to a complete magnaflow Hi flow cats with X pipe, magnaflow straight through mufflers, and BBK shorty headers and the X pipe changed the mid to high RPM pitch of the exhaust to a smoother European sounding V8 exhaust. I have had numerous comments made to me about ":man, does that V8 sound great at high RPM". I like the X pipe improvement in sound immensely on the Ford V8.

jb78L-82

Pretty accurate description of the X pipe improvement.............^^^^^^

gkull

18436572 and you change it to 18736542

LRRLRLLR LRLLRLRR

I think that it sounds smoother, but even old time racers have asked me what kind of motor do I have under the hood. When you have historical trans am cars on the track you can here the difference between chevy and ford

69427

Take what you have above, and expand the exhaust pulse sequence another firing period, and pick eight firings:

LRRLRLLRLRRLRLLR for the standard firing order.

LRLLRLRRLRLLRLRR for the 4/7 swap

They're the same LR sequence. I'm trying to understand how/why would the mufflers react/sound different?

OldCarBum

gkull

if you believe in what the car rags have to say, the X pipe is superior to an H pipe.

lars

I just installed a Pypes "X" system exhaust on a '74 463ci Firebird. I also have an "H" system on my 465 '71 Judge. Both sound the same, and they sound really good. Here is the sound clip from Pypes with the "X" system, and I can verify that this is the way they sound:
Lars

ddawson

I'm not a fan of the x pipe sound at RPM. Gets a little euro sounding.

I like the H pipe sound better. Are you going custom or using someones kit?

AboveTheLogic

I noticed this too and am also curious as to how/why it makes a difference.

pauldana

1 7/8" Kooks headers, 3" mandrel bend SS pipe, X-pipe, Borla mufflers 3" in by duel- 2 1/4" out

525 RWHP 7,000 RPM run