H PIPE VS X PIPE VS STRAIGHT PIPE HELP!!

I ran an "x-pipe" o my 88gt when I had it..replaced the anemic factory h-pipe. with my low buck flow-tech mufflers it was very quiet at idle but really sounded great when opened up....oh, and this was with hooker shorties and with-out cats.

on my '65 I'm building, I will go with an x-pipe again. with possibly some 40 series flows....I have full length headers to go with it.

my vote is x-pipe.

My '65 has a rebuilt 289 with 270 Comp Cam, edelbrock intake and carb.
I've got Flowmaster 40's with straight pipes and it sounds really good!!! I decided against an H or X-pipe.

I've got the 2.5 tubing w/ X-pipe and Magnaflows and turndowns just in front of the rear valance and could not be happier. I was running old 2.25 pipe w/ an H and glasspacks, it's like night and day. What I really like is that crusing around it doesn't make you go tone deaf like w/ the 2 chamber flows will but when you crack the throttle it has a wicked nascarish sound to it, beats the heck out of the way it use to sound which i refer to as ghetto reckneck,you know the beater F150 down the street w/ blown out glass packs and straight pipes out the back that sounds like it's doing 90 when its really doing about 35 up the hill.

GONDO79 said:

I NEED SOME ADVICE ON GETTING MY EXHAUST SYSTEM TO SOUND NICE AND NOT BURN A HOLE IN POCKET.

I HAVE A 64 1/2 COUPE 302 WITH AFTERMARKET PARTS.

I RECENTLY PURCHASED THE FLOWMASTERS 2 CHAMBER 40 SERIES MUFFLERS BUT IM WONDERING IF THERE REALLY MUCH OF A DIFFERENCE BETWEEN HAVE A H OR X PIPE OR STRAIGHT.
I WANT 2 1/2 TUBING AND CUT OFFS BEFORE THE DIFF.

I HAD STRAIGHT 2 1/4 PIPE WITH STOCK MUFFLERS THAT CAME WITH CAR WHEN I BOUGHT IT AND I SOUNDS GOOD BUT I WANT THAT NICE MUSCLE SOUND.

Click to expand...

The consensus is going to be that the X pipe will perform best. Which sounds best will be determined by your preferences.

Some people like how individual true duals sound (it makes the 'pulses' more distinct and clear). Some people the the general 'thunder' involved with an H. And some people like the X pipe for its higher rpm roar.

If I were doing a custom exhaust I'd go with an X. I'm okay with the H my American Thunder setup came with.

As for 'how much' better... thats tough to say. I would believe an X would give you a 5 hp gain over the exact same setup with an H, and that the H will be 5better than the exact same setup with true duals. People who quote other power gains, in general, over-generalize. IE, when someone exclaims "I gained 32 hp when I swapped to a magnaflow exhaust with an x pipe!!!" you might glaze over the fact that they were swapping out an old, stocker true dual setup with 1 7/8" pipes and factory exhaust manifolds and added headers and 2.5" pipes throughout.

IMO... if you, like me, got the American Thunder setup and already have your H pipe and piping... then just keep that for now. It'll sound great and there's no reason to go shelling out tons of money to replace brand new stuff.

If you just bought the mufflers... have a shop fab together whatever setup you like if sounds your thing. Try to listen to some examples of each before hand. If you're basically here to get the biggest dyno number, get the X.

Out of curiousity, any more details on your engine build? Like most things, theoretically an X might make progressively more sense the higher your engine revs, whereas an engine with a stock or mild cam might not really use the X pipe's extra flow as much.

Also, press the caps lock key once.

GONDO79 said:

I NEED SOME ADVICE ON GETTING MY EXHAUST SYSTEM TO SOUND NICE AND NOT BURN A HOLE IN POCKET.

I HAVE A 64 1/2 COUPE 302 WITH AFTERMARKET PARTS.

I RECENTLY PURCHASED THE FLOWMASTERS 2 CHAMBER 40 SERIES MUFFLERS BUT IM WONDERING IF THERE REALLY MUCH OF A DIFFERENCE BETWEEN HAVE A H OR X PIPE OR STRAIGHT.
I WANT 2 1/2 TUBING AND CUT OFFS BEFORE THE DIFF.

I HAD STRAIGHT 2 1/4 PIPE WITH STOCK MUFFLERS THAT CAME WITH CAR WHEN I BOUGHT IT AND I SOUNDS GOOD BUT I WANT THAT NICE MUSCLE SOUND.

Click to expand...

This with straight pipes or an h-pipe your definately going to get more of the that low sound, and that great idle sound, the x-pipe will smooth out your idle a bit.

check out these videos of my car and you can very much tell a difference in idle and the sound on acceleration, although a big part of that is the mufflers too.

2.25" Straight pipes with flowmasters at idle and accelerating:
YouTube - 65 Mustang 347 w/ Flowmaster exhaust

2.5" magnaflow system w/ x-pipe at idle:
YouTube - 65 Mustang 347 w/ Magnaflow exhaust

2.5" magnaflow system w/ x-pipe accelerating:
YouTube - 65 Mustang 347 w/ Magnaflow exhaust

GONDO79 said:

Im running a Performer RPM Hydraulic Roller Cam and lifters,
edelbrock 650
edelbrock performer intake
edelbrock high flow fuel pump
aluminum 3/8 fuel line
ford racing aluminum pullies
ford racing ignition, wires
hedman headman headers
b&m tranny oil cooler
aluminum radiator
A1 Tranny c4 shift shift kit and converter
high flow water pump
steel braded lines
steel braided brake lines
front disc brakes




Built C4 w/shift kit

Click to expand...

Well, for that combination, it probably won't rev high enough (and make power high enough... you have the cam but stock heads and that intake are going really to limit you above 5500 rpm) to really benefit from the X pipe. In your case, go completely off sound preference and cost.

2.5" pipes should be more than enough in your case as well.

And I might as well throw it out there.. you'd likely see some big power gains changing to a Weiand Stealth, Performer RPM, or Performer RPM Air Gap. You might need a drop base air cleaner for them to fit (they're cheap, and it looks like the one you have might work if you use a shorter filter element... thats exactly what I did)... but on SBFs the Performer is basically an aluminum version of the stock 4 barrel intake... the aforementioned intakes all flow considerably better at higher RPMs without losing much, if any, lower end.

Your heads are also limiting you, but the intake is the biggest and easiest change. A used Stealth or Performer RPM could be had for 75-100$ on ebay (and you'll probably get about the same for your Performer... win-win).

for your combination i say either the X or the H pipe will do just fine. i will likely go with the X pipe in my mustang with a similar combination.




next time you leave the caps lock on, i will recommend an O pipe instead.

As far as sound goes, I like the way H sounds over X.