Single or Double X pipe?

I can understand the sound aspect of adding another crossover to the exhaust system, especially on a "picky" mod motor. They never seem to sound "right"... I just don't see it as being worth the added expense and questionable power gains, idk
 
MAT88GT said:
I can understand the sound aspect of adding another crossover to the exhaust system, especially on a "picky" mod motor. They never seem to sound "right"... I just don't see it as being worth the added expense and questionable power gains, idk

Again, :I
 
Okay, I did some research and actually found some actual dyno testing of an "X" pipe. I'm providing a link to the page but bottom line is that while an "X" pipe DOES actually yield a tiny increase in power (1-2hp), it's true value is more in the area of sound tailoring. Read for yourself:
http://www.vetteweb.com/tech/0307vet_xpipe/
 
Katshot said:
Okay, I did some research and actually found some actual dyno testing of an "X" pipe. I'm providing a link to the page but bottom line is that while an "X" pipe DOES actually yield a tiny increase in power (1-2hp), it's true value is more in the area of sound tailoring. Read for yourself:
http://www.vetteweb.com/tech/0307vet_xpipe/

The only problem with that link is that they are comparing the 'H' pipe to the 'X' pipe. So the numbers on that do not do the 'X' or double 'X' any justice in HP ratings. That car already had a crossover pipe on it, so that is like comparing oranges to pineapples.

What a 'H' or 'X' pipe does is it scavenges the exhaust from the opposite bank. As the left bank is exhausting, the right bank is sitting stagnent, so the crossover pipe (for ease of defining) helps scavenge the opposite side so that the exhuast is not sitting in the opposite side so that there is basically less pressure to overcome when that specific bank exhausts, allowing for better flow characteristics.

Now, the difference in a 'H' or a 'X' crossover, is that the 'X' allows for better flow characteristics than the 'H' since the 'X' is more towards the natural flow of the exhaust. Where as with the 'H' pipe the exhaust has to 'bend' thru the connection section between each side of the exhaust.

Now, with the single or double 'X'...I have not seen any HP increase ratings, but I know that it did a nice job on my old car. The exhaust sounded really good....IMHO. I have not heard, that I can think of, a single 'X' on a Mark VIII, so I can not really compare either the sound, nor the HP/torque differences....if there really is any......the jury is still out on that one....it all depends on who you talk to about it.

I do know that with only the exhaust done on my old green car, the RWHP was 247 on a 98 degree day with alot of humidity that day....the actuals i am not sure of, but it was a hot/humid day. That is basically an increase over all of roughly 20 some extra RWHP (most stock Mark VIII's are around 220 or so). What the extra 'X' pipe did for me I do not know, since it was already on there when I did the dyno pull.

As for the price, what does an 'X' pipe cost?? Depending on where you get it, and the quality you are lookin for, they range in price from like $30 -$70. That is not that bad in the general scheme of things when you are performing an exhaust upgrade on a Mark VIII......or any other Mod motor for that matter. Like I said...the jury is still out on whether or not the second 'X' pipe really does anything for sound quality or HP/torque. Maybe someone can do some actual testing between the single/double 'X' pipe. (maybe I will do this, since my recent car I am going to do an exhaust upgrade to it, and I already have 2 'X' pipes sittin around.....maybe I can have the double 'X' flanged so that it can be removed easily, and have the single flange/extended to match the double 'X' length so I can easily swap them out....sounds like a plan.)
 
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The only problem I see...in order for an x pipe to aid in scavenging/accelorating the exhaust gasses is for the crossover to be as close as possible to the collector of the header. The lincolns place this crossover too far back to take advantage of this, and thus only aid in quieting/balancing pressure. My guess would be that replacing the factory H crossover on my 00 ls with an x type wouldn't gain much if any hp/tq. And then to add second crossover back there...

maybe I'll add one of these to the ls and do some dyno pulls sometime
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=33708&item=7932725292&rd=1
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=33633&item=7933497038&rd=1

Just for fun, here's the dr gas site, they invented the x pipe crossover system
http://www.drgas.com

And you can find h vs x comparisons in the archeives of mmff or 5.0 mag's online sites
 
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I think there's a little misunderstanding about the function of the "H" pipe, and therefore the usefulness of the "X" pipe and it's relationship to the "H" pipe.
First of all, I hear too many people talking about "H" pipes as if they were designed to actually FLOW any gases. They aren't. They are only designed to equalize pressures, that's why they are only designed to have a small hole in them as opposed to being the full size of the actual pipe used in their construction. For this reason, their shape and right angles mean virtually nothing. To compare "H" pipes and "X" pipes is actually not a fair comparison. They are designed for two different functions. Well maybe not totally different. The "X" pipe is designed to cross-flow AND equalize, whereas the "H" pipe is only designed to equalize.
The "H" pipe is mainly installed to smooth exhaust pulses and this mainly affects the exhaust note. The "X" pipe is mainly designed to aid in total flow but really only barely out-performs a basic "H" pipe. It's strength is in the tuning of the exhaust harmonics and tone.
Bottom line, there is virtually no performance based reason to install either "H" pipes, or "X" pipes but if you want to smooth out the exhaust note AND pick up a TINY amount of power, the "X" pipe seems to be the way to do it.
 
not to ressurect a very old thread, but this is mine with $24 xpipes from ebay and installed 2.5" piping from front cats back all for $250

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I have been noticing no one likes to go and peice there xhaust system togeather. Or deal with the Mustang pipes. They would rather buy one kit that they know will work with no problems. . .
I chose each piece of mine the mufflers, the X and the tips and what size i wanted paid big money for what i had always heard was the best in the state no joke awesome work 4 pipes total one for each cat to the X and one each side to the mufflers welds ground smooth extra hangers so the system is totally stationary does not move and the tips measured exact distance out when i have the dumps put on will go back to them
 
I've been looking into exhaust threads because I wanna make mine louder but not spend $900 on a entire exhaust system. I'm thinking of doing a X pipe with reso delete and magnaflow mufflers. Will that make it loud? I don't need ear bleeding loud but that muscle car loudness to it. How does hours sound? And do you have mufflers? Lol I can't tell
 

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