Tom 400 CFI

What if any, disadvantage is there to using a common chamber with smooth inlets and outlets, vs. an H or X pipe?

The reason I ask is sound quality. I believe that a chamber (like a dual in/dual out cat that is hollow for example) would produce a more mellow sound, but is there a penalty to pay power wise over and H or X pipe design? It seems like in most aftermarket X pipes, that the window for the two sides to "see" each other are small. Too small.

Tom 400 CFI

Anyone experiment w/this at all??

Tom 400 CFI

ANYONE. Anyone at all...I say!

Zipdrive

There was some stuff on one of the chevelle boards that had some good info on sizing X pipes. Try googling on it and hopefully it will come up. I don't have the link any more. Your right most of the x pipe windows are too small for good gas pressure exchange.

Most of my experience has been dealing with making the best of what you can place under the car. Dyno tuning is really the only way to see how the system is functioning. If you have the money and are willing to experiment on setups, V-band clamps and a couple different sized Xs can make a big difference. I use to get the setup from Burns stainless for the different convergent/divergent angles on the collectors and could 'tune' power gains in different parts of the rev range.

You can't out right say that an X or H or even Chambered collector will make more power (where does it make more power?). It all depends on the engine system. If you are going for tone, pick the one that you like best. Let me know what you choose, I am curious.

Cheers.

Cflick

Theoreticly, the X pipe is best, but angled H pipe can be just as good.
So can no cross over at all !
Depends on how you want it tuned. Tuned for what RPM ?

myvmax1

I'm in on this too. Would really like to know what ya come up with. The Camaro is sitting in the driveway with the Supercomps installed, but no exhaust pipes. Have been putting it off till I find my ideal design. Keep us posted!


Thanks,
Max

Tom 400 CFI

Guys, good posts.

First, I do know that proper balance pipe design needs to occur on a dyno for max tq (at a desrired RPM). In THIS case, however, I'm not looking for power, but rather sound. Smooth, bubbly V-8 sound. I hate to say this, but Mustang-like. Or '05 GTO sounding. My car sounds like crap, and I have a theory that a big chamber, like 8"x3"x2' would smooth, blend, and mellow the sound.

I had the same problem on an '89 Wrangler, w/a SBC 350, outside the frame headers and side pipes. The sound was "blatty" and annoying. I installed a 3" crossover tube, ovalized to join the 2.5" post collector tubing properly. This mellowed the sound dramatically. I'd like to achieve the same effect on this car, but it already has an "H pipe" stock. Which puts me at a bit of a loss starting out.

TA

iTrader: (1)

I did an interview with Darryl Bassani, who has done quite a bit of crossover and "x" pipe research. He explained that the advantage of X pipes is that, since the exhaust exits in pulses, that with a smooth flowing "X", it allows each pulse to exit through both tailpipes/mufflers, thus the area is doubled, or the restriction is cut in half so to speak. Because each pulse will now exit through 2 mufflers instead of one, it usually results in a more mellow exhaust note while still retaining excellent flow and power.

He also stated that changes in cross-section area need to be kept to a minimum, because they interrupt the laminar flow of the exiting pulses, causing reversion or stagnant flow, so sticking a chamber on will probably hurt power.

Obviously, there is no reason for an "X" pipe on an exhaust system that is not true duals.

TA

myvmax1

While I think I understand what has been posted thus far, there is still a question from earlier on that I would like to see some light on. The question about the actual 'crossover' part of the X-pipe being too small, the window that merges the two pipes. Could this be elaborated on please... As I stated earlier I am I need of exhaust for my car but I don't want to make any moves until I know all the facts.

Thanks alot,
Max

customblackbird

iTrader: (15)

i installed a universal Xpipe 3" on my 87 formula 350 with headman long tubes, ans 3" headman extensions into dual force 3" mufflers with turndowns. i have to say i was surprised with the Xpipe the interior cross section was rather large, the cutout oval was almost 3" in height and about 6" in length, the pipes where merged at roughly the 1/2 way point of 2 conjoining 3" pipes. the increased upper RPM flow/power was def noticable even on a mostly stock 350tpi. i had true dual 3" no cross overs before the redone current exhuast. tone has def changed as well, down low id say 2300 and below is like a true duals but then after 2300, it comes alive and the note changes, hate to say but kinda sounds like a stang but with a chevy noise (like the blending of the pulses like a stang does) but doesnt sound like a stang.... this is all in prep for my 383 HSR 500hp motor im throwin in the bird in the spring

i give a thumbs up for xpipe
it was a summit universal xpipe kit. good quality ( i reinforced tho at the conjunction to be safe)

Tom 400 CFI

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