DENT

Whats the deal with duel exhaust , crossover or x pipe verses just duel's ? My Olds is 72 350 4bbl .

redoldsman

I have an H pipe on my 72. At first I didn't and it had a terrible drone. I took it back and they added the H pipe and has been pleasant ever since. I have never used an X pipe.

oldcutlass

What I would suggest is to go to some local car shows and ask around and listen. Go with what sounds good to you.

DENT

Thats interesting, something I am concerned about is the drone. What mufflers are you using ? Thanks.

DENT

That is a good idea , thanks.

RetroRanger

I have straight duals no X no H on my 72 350 w quiet stock style mufflers.

no drone at all its so quiet that all you hear is motor and intake when I punch it. Most everyone w an opinion thinks i need a louder muffler on there but I like it the way it is

z11375ss

No flame intended. Use the search engine on this site. This was debated ad nausea here a short while ago. Check out my vid. Flowmaster 2 1/2s, headers, h pipe.

coppercutlass

I run an x pipe. It's quiet at idle. But when you punch it it sounds gnarly and sounds very aggresive. I have full length headers, x pipe, and hooker aero chambers with turndowns at the axle. It does not drone too much considering I have dumps imo.

adis

Are you talking performance or sound? From a performance perspective An x pipe is used to synch exhaust pulses from the two banks of the engine. This is supposed to help flow, which depending on your set up may result in performance gains. From a sound perspective, my subjective opinion is that in balancing the exhaust you loose some of the burble that is so characteristic of classic v-8 engines, maybe good maybe not. I've got a 72 350 with qjet, performer intake, shorty headers, and a pypes 2.5" x pipe exhaust with summit turbo mufflers and don't really like the sound, but I did get noticeable improvement in throttle response (especially at part throttle) with the addition of the headers and exhaust (and rejetting the carb.)

Redog

Both X and H balance the exhaust.

H is known to produce more torque

X is known to produce more horsepower.

To do true duals correctly, both pipes should equal the size of one. If you are going to run 2.5 inch exhaust, your true duals should be 1.25 inches each

ziff396

I had the magnaflow system with the X pipe at first. It lasted about 2 months. Hated the sound! Went to true duals after cutting out the X. To much pop. Now I am running an H pipe with 18" case pypes race pro mufflers and so far I like it. 2.5" This is about the 4th set of mufflers to get it to my taste. Everyone is different. Just the short version Also, cubic inches and what power you have changes everything.

coppercutlass

My x pipe gained me 2 tenths in the quarter mile.

redoldsman

I have some generic turbos the muffler shop put on in 1993. The Dynomax Super Turbos seem to be really popular and not too loud. There are a lot of threads on here about this subject. Some guys like them loud and some of us old guys like them nice and mellow.

ah64pilot

Long tube headers, 3" pipes, 1 chamber flowmasters, dumped in front of the rear axle...or open headers.

We are in the Racing and High Performance thread right? lol!

Allan R

I'm running an H system on my car. Also run resonators after the mufflers after the axle

DENT

Hey , no flame taken lol , I should have thought of that . Cool video too. Thanks.

61reoldsman

I love that video !! that dog can sure drive a stick!!! awesome sounding 68 BTW ,love the
launches and burnin' rubber

ihengineer76

Redog, I'm not meaning to argue, but 2.5 equaling 2 1.25 pipes isn't correct. When talking about flow, its x-sectional area and the area of rwo 1.25" pipes is actually quite smaller than a 2.5" pipe.

As far a the x pipe goes, its really for scavenging. The momentum of the exhaust gas from one cylinder pulse on one side will in effect "pull" the next pulse of gases from the following cylinder on the opposite side. Kind of the same way tuned headers work.

sicky olds

Ihave X-Pypes installed on my HO and i am not sure on the Rallye lol. I need to see what kind of pipes i have on there, I think they are H though. The X's were kinda hard to install for being my first time but it installed nicely overall.

ah64pilot

Sick, do you need a set of headers? I am trying to sell my Doug Thorley 1 7/8 primary headers so I can get a set of AR Stainless 2" primary headers.

Redog

You didn't read my post right. I said if you do true duals meaning no H or X pipe a 2.5 inch exhaust should be 2 pipes at 1.25 inches each

ah64pilot

So because I am running 2 individual 3" pipes does that mean I have a 6" exhaust?

I've never heard this logic...intriguing.

sicky olds

I am running Hedman headers right now, send me some pics and give me the scoop on those ones you got. I kinda wanna get some stainless ones too lol

ah64pilot

Shooze! Why I gotsta send you pixtcha's when you be seeing dem on ma car win you see'd my car. Dey'ez da onez I gots on my car right now...nickel chromed Doug Thorley 1 7/8" primary wit da 3" collecta.

Shooze, I no you be gotsen some coin jacked up in dat pocket -o- yo's...jes send fo hundo my way an I beez bringen 'em wit me when I'm dere on Sundy...Oh yeah, fo sho...fo-got ta tell yo *** dat I beez comin on Sundy and beez dere ova night till Mundy...fo shizzle!

sicky olds

uhhhhh engrish?

cutlassefi

Mostly correct. An X pipe will typically increase hp/tq above the previous peak.
An H pipe will enhance the hp/torque below the previous peak.

However, an H pipe will lose more up top than an X pipe will cost you down low.
But for a low compression '72, probably with a tall gear, I'd do an H pipe, I wouldn't even consider an X.

Steve, how much you want for your headers? Looking for another set of dyno headers, I already have a set of 2" Hookers, need something smaller.

Thanks

ihengineer76

Two pipes at 1.25 inches each do not equal a 2.5 inch pipe with true dual exhaust. When I said x-sectional area that is CROSS sectional area. It has nothing to due with an x or h pipe. Volumetric flow i.e. exhaust flow is the velocity of the gas multiplied by the cross sectional area of the pipe. Area of a pipe is equal to 3.14*diameter squared over four. So for two pipes to equal one 2.5 inch diameter pipe, the diameters would need to be the square root of 2.5 which is approx. 1.58 inches. I'm not trying to be a jerk about this, but rather just trying to clear up any confusion.

Tom

ah64pilot

Too much for dyno headers lol! They are nickel plated Doug Thorley's from when he owned the company. They are 3/8" flange, thick wall tube, and 3" collector.

I really shouldn't sell them yet, I've got to get the money together for the AR's I want.