Benefits of X pipe versus H pipe?

[Black 6.2L SS]

So I keep reading about some guys changing out the H pipe to an X pipe and others not doing so. I looked under my car (NPP) and it seems pretty clear that I have an H looking pipe after the cats. The crossover part is pretty small but it doesn’t appear to cause a restriction....the air just flows past the connector part and out the back.

So I’m wondering, why change it? Is it because of the firing order and exhaust pulses getting jammed up or something? Better sound?
I think my factory pipes are 2.5” so maybe when guys increase to 3” it’s just better cross flow to put in a 3” X pipe as well?
Thanks in advance for the ongoing learning.

[VR Baron]

H pipe for old v8 sound and more low end tq. X pipe for more exotic sound, and higher reving and a bit more power, maybe. Don’t do a 3” x pipe with a 2.5” exhaust.

[rontammy0]

There is zero performance gains switching from one to the other. As mentioned the x pipe gives you a higher tone while the h pipe is slightly deeper.

[Benman]

when guys increase to 3” it’s just better cross flow to put in a 3” X pipe as well


This is the main reason I went to the X pipe, connected to factory NPP mufflers. Love the sound.

[lazerlemonta]

Originally Posted by VR Baron

H pipe for old v8 sound and more low end tq. X pipe for more exotic sound, and higher reving and a bit more power, maybe. Don’t do a 3” x pipe with a 2.5” exhaust.

LOL both of my cars utilize the stock 2.5" NPP and made more power then anyone else's bolt on set up. My current set up on the C6 is the same 3" all the way to the stock axle back and makes 562 at the wheels NA SBE LS3. Not sure why you would direct a guy not to use a 3" X pipe? Please show me how much power he has left on the table. I dropped my whole muffler system on the C6 for last dyno and made zero change when it was still bolt ons......

[Avenging Orange]

Gimmick....stick with you H.

[VR Baron]

Originally Posted by lazerlemonta

LOL both of my cars utilize the stock 2.5" NPP and made more power then anyone else's bolt on set up. My current set up on the C6 is the same 3" all the way to the stock axle back and makes 562 at the wheels NA SBE LS3. Not sure why you would direct a guy not to use a 3" X pipe? Please show me how much power he has left on the table. I dropped my whole muffler system on the C6 for last dyno and made zero change when it was still bolt ons......

Oops. Miss read your post. Thought you wanted to use a 3” x with a 2.5” catback

[lazerlemonta]

[QUOTE=VR Baron;10547552]Oops. Miss read your post. Thought you wanted to use a 3” x with a 2.5” catback[/QUOTE
They both used 3" to 2.5" and my C6 still utilizes this set up

[VR Baron]

[QUOTE=lazerlemonta;10547598]

Originally Posted by VR Baron

Oops. Miss read your post. Thought you wanted to use a 3” x with a 2.5” catback[/QUOTE
They both used 3" to 2.5" and my C6 still utilizes this set up

Ok. Didn’t know gm would use 3” pipes and x pipe and neck down to 2.5 st the mufflers? Don’t see the point of that. But method in the madness as they say

[lazerlemonta]

[QUOTE=VR Baron;10547620]

Originally Posted by lazerlemonta

Ok. Didn’t know gm would use 3” pipes and x pipe and neck down to 2.5 st the mufflers? Don’t see the point of that. But method in the madness as they say

Miss understanding. GM uses 2.5" full exhaust. Your header collector is 3" so use 3" all the way back to the axle and reduce to the stock 2.5"

[SSEssence]

X pipe gave mine a slightly higher pitch sound, I like it

[VR Baron]

[QUOTE=lazerlemonta;10547625]

Originally Posted by VR Baron

Miss understanding. GM uses 2.5" full exhaust. Your header collector is 3" so use 3" all the way back to the axle and reduce to the stock 2.5"

Ah. Looks like at your power level 3” might help. At my 439 hp level mine didn’t do squat but made a deeper tone, and got a great deal on it. Necking down to 2.5” can’t see how it helps to have 3” in rest if system, peer wise. I see you’re point to fit headers. But plenty of 2.5 “ catbacks to fit to headers. But if it works, cool!

[olblue75]

I installed a full Z28 NPP on mine with a X Pipe from a C7 Corvette, if you PM me your cell number I'll send you a sounds clip from NCM. Also have long tubes and HF Cats

[lazerlemonta]

[QUOTE=VR Baron;10547680]

Originally Posted by lazerlemonta

Ah. Looks like at your power level 3” might help. At my 439 hp level mine didn’t do squat but made a deeper tone, and got a great deal on it. Necking down to 2.5” can’t see how it helps to have 3” in rest if system, peer wise. I see you’re point to fit headers. But plenty of 2.5 “ catbacks to fit to headers. But if it works, cool!

If your buying an X or H pipe per say, you buy the next best thing right? So 99% buy the 3" with future plans of completing the 3" system. No sense limiting yourself to 2.5" exhaust.