quick exhaust question

[mrcomedy104]

i recently got 2.5 inch dual pipe exhaust work done to my 1972 c20. with 2.5 inch cherry bombs. it sounds amazing!!!!! a lot of my friends including my brother told me that i should have gotten X pipes or H pipes done instead. the previous owner of the truck put a 1967 327 motor in the truck, i'm planning on putting a stock 350, or a 383 in it. would the X or H pipes be better for the truck then the dual exhaust i have on it now? they said back pressure is good for the truck

[litew8]

I don't know about back pressure being good or not, but I think an x or h pipe run is suppose to be slightly better. I wouldn't think it's all that much and you should be fine to leave it as is. 2.5 is more than plenty large. You want the engine to BREATH as much as possible (e.g. exhaust pipe).

Here's something someone wrote up:
"This has the most effect when there's a bunch of time between pulses...in other words, at low rpm. As the revs rise, the pulsed flow becomes more and more like constant flow, and the scavenging effect is diminished. So, at low rpm I need a small pipe to maximize scavenging, and at high rpm I need a big pipe to minimize pressure drop. My exhaust pipe can only be one size, so it's a compromise. For a given engine, one pipe diameter will make the most overall power (i.e., have the largest area under the curve on a dyno chart)."

Read the rest: http://www.dsmtuners.com/forums/freq...kpressure.html

[mrcomedy104]

thank you for the info, i thought it wasn't a big deal as long as its breathing.

[mrcomedy104]

they were also talking about the sound, the H and X pipes make it sound better

[litew8]

Try youtube for examples. I don't know about better, but different for sure.
Bigger isn't necessarily better, either. I think the size you've got is just right for future upgrades.

[piecesparts]

Actually the H pipe and the X pipe both will change the amount of torque developed by the engine, by assisting in evacuating the exhaust gases from the cylinders better. The sound is another plus, the truck will not sound like a tractor working in a field, it will smooth the sound out. The X-pipe is the most efficient of the two choices, but I personally would not put the exhaust in without one or the other being in the system. For my gas money, I want every dime to make some kind of power and the fact that the cylinders are not being swept clean effectively, during driving, would be wasting my money.

The exhaust is all about cleaning the cylinders and not creating a reversionary pulse that would hender the movement of gases through the engine.

[Sklptrljay]

I believe H and X pipes are most beneficial for low end power, as litew8's post mentioned.

That is the extent of my knowledge on the subject.

[litew8]

videos
http://www.autoanything.com/exhausts...xhaust-systems

x (high rpm) vs. h (low rpm)
http://www.autoanything.com/exhausts...pipe-vs-h-pipe

I don't know much of anything on the subject either. I just think the quickest way from point A to point B = a straight line. Not curved.

[litew8]

Much larger engine. Has an x pipe setup. Not mine.
1970 Chevelle 496 Big Block walk around 3" Magnaflow x-pipe exhaust

1970 Chevelle 496 Big Block walk around 3"...

[mrcomedy104]

thank you very much, i personally love the way it rumbles. i just thought i had made a mistake since it was brought up by a lot of people, i'm keeping it like it is, ill just save for the drop kit instead of worrying about the exhaust

[AirSpeed]

Originally Posted by litew8

Much larger engine. Has an x pipe setup. Not mine.
1970 Chevelle 496 Big Block walk around 3" Magnaflow x-pipe exhaust

1970 Chevelle 496 Big Block walk around 3" Magnaflow x-pipe exhaust - YouTube

That is a beautiful car! I miss my Chevelle so much! Nothing like driving a real muscle car. Again, gorgeous car!

[mrcomedy104]

thats so clean, it sounds so aggressive