Alright, so..

I know people are usually discussing the differences between X and H pipes. I'm pretty sure that they are both used to balance out the pressure between the headers and they each have their specific noises.

X pipes are supposed to sound like Nascar, and H pipes have a more choppy noise.

The only thing that I don't get is how everyone claims that they add horsepower and torque. Is this true? or is that only if you are still running manifolds?

By the way, our "pipes" for the time being are two 4 foot sections of 2.5" metal conduit from Lowes with 1 big washer per pipe as a baffle. We had to remove the cherry bombs that were rubbing against the drive shaft and make our own straight pipes. So obviously its going to sound completely different until we get some real mufflers.

Speaking of which, (sorry about all the questions) whats the sound difference between Flowmasters and Magnaflows? I've heard Flowmasters are more tinny.

Anyway, thanks for the help!

And one more question! I know this will sound annoying, but the only real high quality exhaust sound sample I know of is the noise from the Bumblebee Camaro in Transformers, so does anyone know that exhaust setup by chance?

Thanks.

 

Can't answer all your questions, but the first one I can. The H or X pipe is making more HP, whether you have factory manifolds or headers, but it does better with headers. The reason it makes more HP is that the exhaust gases are scavenged by the other side firing while the one side is still exiting the exhaust system. Sort of like a paint sprayer siphons the paint by blowing air across the pick up from the container. It pulls the exhaust along where they meet, making it flow better and increasing HP a little. This is also why it does less with cast headers, as that system already ties the 4 cylinders together, so it doesn't have as much effect with the smaller outlet of a cast header.
The X or H will also make your exhaust system sound a little quieter, as it shares that joined section, so you don't get the sound of individual cylinders firing. Now if you want the system to sound more throaty, and hear the big lumpy cam empasized, then don't connect the two sides in any way.
I've intentionally left mine separated because I like the sound, but I've also got pretty quiet mufflers, and didn't need anything to help quiet the car down.

 

You can go to my fquick account (below in the sig) and listen to my Flowmasters. They're 50 series with a 3 inch mandrel bent exhaust and X-pipe.

I noticed that my lumpy cam sound went away with the X-pipe as 1971BB427 states.

 

flowmaster and most exhuast companies have sound clips on the web sites,check out pypes performance exhuast the have systems made just for are cars that will fit were the stock stuff was but its better flowing and sounds really good. also go to youtube and look up diffrent brands of exhuast on there.

 

The best way I can describe Flowmaster, they sound like a power boat that dumps the exhaust near the water at low to mid throttle. At WOT they roar. I've personally run 2.5 40 series, And delta flows on my truck. I have a set of 3 in 30s going on my 78 with an x pipe although I have no idea what it will sound like.
P.S. Four feet of staight pipe into washers. Hmmmmmmm. I would have gone coat hanger first. I'm not knockin ya, But thats the best way I've ever heard to rob power with an exhaust. The hole couldn't be more than 1-1.5 inches.

 

Alright guys, just thought I'd check back in. I am happy to inform that we have re-fitted the Cherry bombs! (good thing we saved them!)

It's back to (somewhat) high-flow 2.5" exhaust and straight-thru glasspacks. Thanks to 77 Nomad, I had realized the restrictions of washer baffles and with the new setup, my engine can breathe! So thanks again!

And the best part is the sound.. nice and smooth inside and deep and bassy as hell from the outside. And I must admit, it's pretty darn close to the '10 Bumblebee noise that I love so much..


So heres a Pic of the current setup. This is still somewhat temporary. Just a barrowed MIG welder, angle grinder, and a few new hangers from Autozone.

 

X pipes and H pipes only work on full dual exhaust systems on V8 engines. The reason being that there are 2 cylinders in each bank that fire one after the other instead of alternating bank to bank. When the two cylinders fire there is more back pressure on one side of of the exhaust system than the other. The cross over connection allows gas from the high pressure side to flow over to the low pressure side. This allows better exhaust scavenging, especially if mufflers are used.