flyfishinwoman

Been doing a little research on exhaust systems, and am considering the advantages/disadvantages to using an x-pipe setup. What are people's thoughts and real-world conclusions between a straight-back system and one with an x-pipe? Thanks.

redwingvette

I would not run without one.
I use to have a straight back 2" stock replacement system that I cut in a H-pipe.
Now I have a Magnaflow 2 1/2" system with the x-pipe. Nice sound without any drone.
Magnaflow install

dburgjohn

I can't say much about performance increase, but it does get rid of the bad drone sound. I would say they are a good idea.

73, Dark Blue 454

I agree with the above, but not all X-pipes are created equally. I've seen designs that would hurt performance. I like to see the bends of the X-Pipe sort of kiss with a small opening between the two.

75+78 Corvettes

My 75 with dual straightpipe and flowmasters will not win any performance awards with its l48 but it has as nice staccato to the exhaust that is remeniscent of sidepipes. neighbors love it.

69 Chevy

drone, n. 1. a continuous and monotonous humming or buzzing sound.

Funny that I've never experienced the dreaded 'drone' yet I've had header sidepipes installed for 35+ years and I think it's next to impossible to connect a Y or X pipe to this type exhaust. Which makes me wonder what exactly causes this 'drone' sound? Some part of the exhaust vibrating against the chassis? (excuse my old school terminology, I meant to use the more descriptive term, platform) Perhaps the Corvette engine coupled to a slushbox trans? Perhaps airplane gears which has the engine only running above idle speed whilst cruising at highway speeds? Perhaps something altogether different? There's got to be a reason why my mouse motor purrs and these others drone.

wcsinx

The thing about exhaust noise is everyone has a different tolerance, and it's VERY subjective. My C5 has B&B Bullets which a lot of people think are obnoxiously loud, but honestly I think they're pretty sedate until I put my foot in it.

But to the question at hand, an X-pipe will reduce drone as well as the "motorboat" idling sound that straights can give you. I doubt they'll make an appreciable difference at WOT, but they do help the streetability of your car somewhat.

flyfishinwoman

Does an x-pipe really help performance by evening out the exhaust pulses and improving scavenging as some manufacturers claim it does? If these are the primary reasons for applying an x-pipe, I can see the logic. But, if it doesn't really improve anything, then the results are all in the ears of the beholder, so to speak. I was wondering if anyone has actually compared the two types of systems on their or someone else's vehicle.

TheycallmeDave

Im afraid all we have to go on is what we read in car magazines and mfgr's , and they all say that it improves scavenging the exhaust. You get a side benefit from it changing the exhaust sound especially at cruising speed..or at least it did on my 1970 BB Coupe. I cant feel any performance increase but im glad i did it. Wish i could have put the 'x' in front of the crossover support close to the engine instead of behind the crossover support., but it is not feasible with longtube Headers.

Shark Racer

You know the sound an engine makes when it loads up? That's drone. (Like when it's about to stall - I'm teaching someone how to drive stick and hearing this a lot, or if you're trying to speed up a lot in a high gear at far too low a speed.)

Lots of aftermarket systems do it, even the ones that claim "no drone", especially in modern cars with the really tall overdrives. The solution, of course, is to downshift.

My 78 doesn't drone, but it has 3.55 gears which means it's almost always above the highest load points.
I can make my truck drone on demand and it has stock exhaust, just an intake system.

Ironcross

I see no advantage in fact I see a hindrance where they weld one pipe to the other as the opening is smaller than the pipe it connects to in the 'X......and a drone is what I would call from those tin cans referred to as mufflers....A Walker {Dynomax} would not have the empty tin can with deflecting flat baffles with that obnoxious sound I will call resonating......as they use fiberglass....a possibility the performance manufactures would want a 'X as its only more money to them .......and a balance tube is like a small crossover that may benefit the flow, but a 'X the way its made is very suspect...My race cars never needed either one.....there straight out

ajrothm

I would definitely run an x pipe to help quiet things down, as for performance gains over an H I am not sure....they definitely appear to flow better then an H pipe... assuming you are using a GOOD quality x pipe....not a muffler shop special....

Here is mine, it is a Dr Gas 3" stainless steel x:





My train of thought is, ANYTHING you can do to promote exhaust flow will gain power... I will soon be modding my headers with merge collectors and slip fit flanges...

To the OP.... I may not hack up a perfect exhaust system just to add an x pipe, especially on a stockish type motor but...if I was building a whole new exhaust system, I would definitely add the X pipe...there is no downside to it.

SH-60B

I have full length headers and the Magnaflow system that I installed last week without an X or crossover pipe and the car has no drone at any speed or load up to 100.

biscuitville

The summary below was taken from: The Strong Silent Type

"You can build a quiet exhaust system that performs almost like open headers."

By Jim Hand & Tom Hand

Using a single test vehicle, they compare open systems to differing size pipes, different mufflers, and different configurations. The link is at the bottom.


Recommendations:

1. Always use a crossover of one kind or another. Our tests indicate that the X type gives additional improvements over the H type.

2. Mount the mufflers as far to the rear of the chassis as possible. An important characteristic of the exhaust system (behind the headers) is its ability to dissipate heat energy. Heat loss brings with it, gas volume reduction, enabling smaller mufflers and pipes to be used without penalty.

3. Always us the largest case muffler that you can fit under the chassis possible. The larger internal volume allows additional acoustical energy to be absorbed ,dissipated and eliminated.

4. Unless an engine is in the 500+ horsepower level or run at very high RPM, the maximum tailpipe size required for minimal power loss is probably 2.5" diameter. When the exhaust pipes and mufflers drop the temperature significantly, the volume of the exhaust gas is reduced and tailpipe sizes is not as critical.

5. When you must adapt various pipe sizes, always use long tapered cone reducers, such as, those available from Flowmaster. You can also use a crossover that has reduced pipe sizes built into it.

http://www.boyleworks.com/ta400/psp/exhaust.html

Gale Banks 80'

X Pipes are "In Style" these days. If You don't use one You will be " Out of Style"

roscobbc

On my 489 I have just swapped-out my 1 7/8" Hedman headers and twin 2 1/2" system with 'straight throughs' to - 2 1/8" underfloor Supercomps with a custom 3" stainless system with 'X' pipe and 'straight throughs'. With the old system it didn't 'drone' and had a nice 'old school' sound. The new system oddly enough DOES drone below 50 mph (but I am running a 3.08 rear-end) - sound is different - at higher revs people following me say it now sounds more like a modern multi-cylinder race car - it 'howls' when revving hard.
The important thing (for me) was that the performance HAS noticeably changed - torque (at 565 ft/lbs) was never lacking it now seems far more linear that before and it has livened-up higher-end rpm useage.

Ironcross

Yep, ......

cant join the bench racing crowd witrhout one......sort of like the color of the day as too whats in at the old crusing grounds

DIP51

I don't know if you should x or not, but my Magnaflow system came with the x pipe and it sounds GREAT!!!! I realize all this is subjective, but I would recommend this system to anyone. Love the look of the dual tips on each side, and when you plant your right foot...!!!

Les

I remember reading that quite some time ago- good stuff!

I agree with Alan's last 2 paragraphs. I would add that if you have a mild motor the cost of the X pipe may not be worth minimal gains for you. So, the H pipe may be a better option if cost is a factor. There's ample proof that X pipes add performance for high horsepower motors, so given that circumstance it's a no brainer if you want max performance. FYI both of my Vettes have H pipes, so I'm not saying that to justify my own choices.

By the way Alan, get that thing out in the mud or something. It's way too clean underneath!

wcsinx

More details on that cross-member

did you fab that up? :