#1  
Old 11-23-2020, 10:40 PM
4dblnkldude's Avatar
4dblnkldude 4dblnkldude is offline
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Default X pipes, crossovers what ever you call them.....

In 1996 or so I had an an exhaust shop put on some 3" head pipes with a hand fabbed x pipe, flow masters and 2 1/2" tail pipes. This was 400 with a 2801 summit cam, 4x heads, a holley, and headers...nothing special. The car sounded great I thought. I changed headers and welded 3" pipes straight to the mufflers 6 years later. It sounded so much better! About 7 yrs ago I changed headers and put on a summit x pipe kit with super 44's. This was with a hopped up 455, more radical cam, etc. I didn't like the sound on day one. Since then I've done a half dozen or so exhaust systems on buddies cars and so forth all with no crossovers. Most recently I changed the rusted out mufflers and tails on my 81 TA. This has 2 1/4" to 2 1/2" flow master 40's with 2 1/2" tails. It sounds awesome with a bone stock 400 with manifolds. You can hear the exhaust notes perfectly. Anyone else notice how the crossover further muffles the sound? Is it worth it to even have one? Really how much hp do you lose? If it is 6-7 hp I'd rather have the sound.

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  #2  
Old 11-24-2020, 02:19 AM
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Greg Reid Greg Reid is offline
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I'm not crazy about the x pipe sound on my car either. It definitely has a different, 'tamer' sound to me than straight duals. I'd be surprised if it added more than 10hp.

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Old 11-24-2020, 07:20 AM
Steve C. Steve C. is offline
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When trying to decide between an X-pipe and H-pipe, the main variable to consider is sound. X-pipes tend to be higher-pitched and more raspy while H-pipes have a lower pitch and sound more like a deep growl. In terms of horsepower and torque, there are some differences. X-pipes tend to have better power while H-pipes have better torque, comparatively speaking. If you're debating the two for your daily driver, this shouldn't be much of concern because the difference isn't that significant. However, if this is for your track car then you always want the most power you can get. That's where the X-pipes would be a better choice.

As combustion gases travel out of the header collector and into the intermediate pipe, if their progress slows down due to backpressure, a balance pipe redirects them to a less congested flow path. The name ‘balance pipe’ should be a clue as to why X- and H-pipes work so well. Just like the name suggests, they help to balance the flow between all the cylinders. Beyond that, they can even help with scavenging by having cylinders from the opposite bank of the engine create a negative wave to increase the overall flow of the exhaust.


And regarding different muffler brands.... for MANY the sound of Flowmaster mufflers is a love–hate relationship !

"If the damn things didn't drone so bad, they wouldn't be nearly as annoying"


.

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Last edited by Steve C.; 11-24-2020 at 07:37 AM.
  #4  
Old 11-24-2020, 10:25 AM
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leeklm leeklm is offline
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I had my current motor running a 3" system in 2 cars, one with X and one with H. Not completely apples to apples as the 73 had the longer case ultra flow mufflers vs the short ones in the 68.

Both cars sounded good IMO, and I typically do not like obnoxious sounding exhaust. Open pipes even bother me at the drag strip lol...

To Steve's point, the 73 with X had a higher pitched sound and overall was quieter (much of which is impacted by a longer muffler). The 68 with H has more of a throaty "grumble" to it.

It a person is after more of the muscle car sound with the benefits of a balancer pipe, my minimal experience would suggest the H pipe.

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Old 11-24-2020, 01:37 PM
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You might have seen this before, but this is a comparison I did.

http://forums.maxperformanceinc.com/...d.php?t=836737

I'm not a racer so the extra power from the x-pipe means nothing to me. Ever since I heard the H-pipe on my '70 I was hooked. My '73 has it as well.

https://www.youtube.com/watch?v=OjFDfmyE7lQ

I have the X-pipe on my '70 GTO and both of my '78 T/As. As time allows all of them will be changed over to H-pipes.

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Old 11-24-2020, 10:35 PM
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4dblnkldude 4dblnkldude is offline
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Thanks for the replies fellas!! Nap...I effing love the sound or the RA4. Once I take the engine out (friday) get the cam in, rear main seal sealed, new clutch, hydraulic slave clutch in... I'll try a little exhaust comparison myself!

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Old 11-25-2020, 02:42 PM
ta man ta man is offline
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I'm sure a few here have used Walker Ultraflow mufflers. Great flowing mufflers, straight through design...with and without a crossover they are totally different. Full throttle without a x its like no mufflers are on the car..sounds great but loud...I had a set on a full 2.5 inch setup with no crossover at about 375hp..When I swapped a X crossover in..the idle still sounded similiar..maybe a little crisper..but the cruise and the biggest change was the wide open throttle dropped in decibels quite a bit. It also picked up at the dragstrip a little in time and mph.
Exhaust is all relative to the owners taste..some like it loud..some will search for the last hp in their exhaust setup..some want it quieter..some want it quiet and fast..and then add in all the different sounds from the mufflers..

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Old 11-25-2020, 02:48 PM
ta man ta man is offline
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The one thing I can also add is the idle still does sound fantastic with an x pipe. With my car with full 3 inch exhaust..it is relatively quiet for 600hp..at idle at the back of the car you can hear and tell it has a bit of compression and a higher lift cam and a bit of duration ..it has a "fast car vibe" to it...doesn't also have to be annoying loud to sound fast..... Meanwhile on the highway at 70mph..it is very quiet inside the car..not much louder than a regular car.

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466 Mike Voycey shortblock, 310cfm SD KRE heads, SD "OF 2.0 cam", torker 2
373 gears 3200 Continental Convertor
best et 10.679/127.5/1.533 60ft
308 gears best et 10.76/125.64/1.5471
  #9  
Old 11-25-2020, 02:53 PM
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Agreed. It is almost like asking someone what their favorite color is.

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