New pipes are next: Any opinions?

[dale_z28]

Ok, we're now almost ready for the exhaust system. I know my car didn't come with chambered, and I've spoken with Eric Gardner and his recommendation is what Gardner Exhaust  calls a "deep tone" with the dual-inlet/outlet muffler hanging parallel to the axle. This is actually what my car had on it when I bought it, but at the time I hated it. Keep in mind I was a kid, and I wanted my first car to command attention. With cherry bombs and a lead foot, it did!
Now I want a good sound, but not so loud we can't converse in the car at highway speeds (which Eric told me would be difficult with chambered pipes, dang it!). So....I'm opening the door, who recommends what? I'd like to stay pretty close to something original, but a balance - or X pipe - isn't out of the question.  I should add: I'm going to run Hooker Super Competition headers

[abiddle]

I have flowmaster installed 13 years ago, still sound great, didn't cost much, and he used the original hangers. I would do them again.

Andy

[X33RS]

If you don't want OEM Gardner stuff, then my favorite F/X-body system to run is the transverse setup from Pypes.   It's all stainless steel, has an "X" cross over, it's all 2 1/2" and mandrel bends.  For just a hair over $500 at Summit you can't go wrong for a complete stainless system.
   This system was worth 3 tenths and 3 mph on my Firebird over the stock Gardner system.  I run this system on 4 different cars.  No drone, it's not obnoxiously loud at all, actually very quiet inside the car, and when you step on the pedal it makes enough noise to be noticed, but still not obnoxious.  Even gets approval from my wife 


http://www.summitracing.com/parts/pye-sgf70/overview/year/1969/make/chevrolet/model/camaro 

[dale_z28]

If it has your wife's approval, I need to check it out! That would also save me about $700 over the Gardner system

[L78 steve]

Gardner systems are nice to look at but are power killers as were the stock systems. I like the Flow Master systems best. I have a 70 L78 Nova with manifolds and a Garner cross flow system and it runs like a turd.
But the 67 and 69Z with Flow Masters are a blast.

[X33RS]

I ran the Flowmaster Force II tranverse system on a car for a while, I liked it well enough.   One thing to keep in mind with these, Flowmaster no longer sells the Force II system and now only sell the American Thunder transverse version which is much louder.   

[cook_dw]

Hooker headers with 2.5" exhaust, x pipe & Pypes crossflow muffler exiting in stock location.  396 with baby cam.

https://www.youtube.com/watch?v=7ONw47qZ2uc

[Mike S]

 Has anyone bought a system from The Parts Place? They have what looks like correctly bent pipes with the ripples and correct diameter and offer a deep tone configuration.  That may be an option for a driver/show car. I'm eyeing one of those aluminumized systems they sell to replace the SS system I put on my car in the mid-80's (one pipe taps the convertible floor brace). I'm trying to get resonators but so far no luck, unless the Firebird resonators fit Camaro.

Mike

[janobyte]

Hung a Flowmaster Transverse (American Thunder)system on the car some time ago, behind Hooker Super Comps.

I love the sweet sound of open headers, so not obnoxious enough for me! Seriously now, big improvement over the Cherry Bombs that were on it, nice not getting CO poisoning at idle, I feel more power(seat of the pant) Low choppy sound at idle ( see Cook's vid). Must agree with Pypes though, cannot go wrong for a stainless system at that price. Have not read any negatives fit and function.

Have read the data: chamfered exhaust killed power. Surprised the 2.25" inch transverse system actually made more.

[janobyte]

Meant to say "felt", this was a few years back. Personally, on the bubble what's going back under mine when it's all bolted back together. Like X33, more of an "event" guy than "show".

[CDB]

So the consensus for upgrading first gen brakes is that Gardner will have the stock look, but they'll be a power loss (as were the stock exhausts)?

That's kind of disappointing, but I guess it makes sense.

[jeff68]

I guess it's only a power loss if you are going back to an original type Gardner system from a 'performance' system.  If you are out to get every last bit of power out of the engine, then go with a high-flow system.  If you are more of a 'correct' exhaust guy, then get the Gardner system.  I don't think the engine will feel restricted or held back by the stock type exhaust.  I have the Gardner system and my little L30 327 seems to have plenty of power!

[69Z28-RS]

From what I recall JohnZ telling us once, the 'factory chambered system' allowed 7 hp less than the alternative Z28 system that was being considered (I assume when the '69 Z28 was being developed/finalized).  I also assume the 'alternative Z28' system was the single transverse muffler (no resonators)...  Marketing made the decision to make the chambered system std on Z28, over objections from engineering.  After a few months, due to the noise issues in some states, the chambered system ws replaced by the single transverse muffler (no resonators) on new Z28s.   Only very late in the year were the resonators added to further quieten the exhaust, again due to issues in a couple of states.  After hearing this, and finding out my car production was too late in the year for chambered, I decided to sell the NOS chambered system I'd had for 30+ yrs...

PS.  I DO love the sound from the stock chambered exhaust which is comparable to the side exhaust from mid year Corvettes...

[X33RS]

Here's a little different approach I took on the Z28.   I want to extract what is there out of the engine, but want to keep the stock appearance.  My Z still has it's born with exhaust system and just looking at the design, the crush bends, 2 1/4" head pipes etc... I knew I didn't want to stick with it.

I want mandrel bends, 2 1/2 inch, but still retain the transverse muffler.  Usually I go straight for the Pypes system.  But there was a catch for me in this case.   It's important to me to keep the stock appearance so I'm going to incorporate a new set of the factory 2" tail pipes.  I just prefer the appearance of those stock pipes out back.     However, Pypes transverse muffler exits are opposite from the factory setup.  I went searching.

Found that Dynomax makes a nice looking 2 1/2" mandrel bent system with an "H" pipe and uses the transverse muffler sold under the Thrush line.   Uses a Dynomax Turbo muffler that has conventional outlets at the top of the muffler like the OEM system.  With a simple reducer I can attach the stock tailpipes without much fuss and retain the stock appearance at the rear of the car.  Best part is that Dynomax sells this system for only $260.  It's not stainless, but is aluminized which will last me a lifetime out here in the desert anyway.  Should be a fairly quiet system with a little bite but not obnoxious, and free up a little power.

I have this stuff here it's just a matter of finding time to install it.

[69Z28-RS]

Doesn't the '2 input, 2 output' transverse muffler itself serve (at least partially, given it's a ways back from the engine), the purpose of an H or X pipe?... ie.  The exhaust from both sides of the engine can escape via both outlet pipes....

[X33RS]

I don't know if this will answer your question Gary but I do know that the "H" or "X" setups are most effective close to the engine 12"-18" back.  Has something to do with the hotter exhaust gasses that are moving quickly vs the exhaust gasses having more time to cool as it travels towards the rear.
  That's also the reason why running smaller tail pipes (smaller than the rest of the system) has no measurable affect on HP output.  By the time the exhaust reaches the tailpipes it's cooled and traveling slower.

   There are transverse mufflers on the market that actually have an "X" design inside the muffler.  Dynomax makes one that I know of.   But that theory I stated above makes me wonder how effective it would be.

The Dynomax transverse system I bought here...   http://www.jegs.com/i/Dynomax/289/89021/10002/-1 

Uses a super turbo Dynomax muffler design which is their quietest, but flows more cfm than the stock Z28 deep tone muffler and as a result I think is slightly louder than a stock system (plus the pipes are bigger too so that affects sound).  However if you want more, you can substitute this muffler with a couple of different Dynomax tranverse mufflers like the ultraflow or the welded case "X" design.   Each one will have a different sound I'm sure.  But for only $260 for the system with the turbo muffler you can afford to experiment a little if someone wants to. 

[69Z28-RS]

I think you are right about all that Larry...   the closer to the engine, the more effective it is... although I think it would be effective wherever it is located (to varying degrees).  I'm fairly certain that the stock transverse muffler shares a resonant chamber between the two ports, although I haven't seen one cut apart...  I don't see much reason to have two pipes sharing one muffler housing unless that were true.

PS.  I've always thought that turbo mufflers provide a great sound... 

[X33RS]

I went this route with the stockish turbo muffler in hopes that my wife approves.

She is fine with the Pypes transverse systems I've used, they are actually rather quiet inside the car with no drone at all, so I suspect this Dynomax turbo muffler should be similar if not maybe a tad quieter.

If it passes the wife test I may pull the muffler and install the dynomax ultraflow for a little sound comparison.  If I get in trouble I can always switch back.

I just didn't go with the Pypes on the Z this time around (even though it's a wife safe system) because I really feel the need to run factory reproduction tail pipes.  Can't do that on the Pypes system.   If you have ever seen the muffler design on that system it's rather unique.  It's a transverse "race pro" with one side having the inlet coming in the top on one side and exiting the bottom on the other side.   On the other side the inlet is on the bottom and the outlet comes out the top on the other side.  Making the tailpipes specific for the application.  This particular cross flow muffler has a straight through design (same pipe enters and exits the muffler case) hence the reason for the opposite enter and exit locations on the muffler.

 Fitment has always been excellent, I like the stainless construction, the "X" pipe, and most important the sound level is great with no resonance inside the car.

[69Z28-RS]

I wonder if any of the 'X/H pipe fans' know that Chevrolet actually designed/installed an 'H pipe' on the factory stock dual exhaust '57 Chevrolets???   It was VERY close to the engine, actually connecting the two exhaust pipes right out of the manifolds and the connector pipe running around the front of the engine...  For some reason, I think that '57 was the only Chevy (I'm aware of) that did this from the factory.

[Z10Mike]

The C1 Vettes with dual quad and FI systems had the dual exhaust cross over pipe at the front of the oil pan.  My '60 270hp job was set up that way.  It ran strong and had a unique tone.  Miss that car.

[X33RS]

Yep, even Ford has been doing it for decades on all their performance stuff.  My 69 SCJ has a factory "H" pipe.  Even my sons 89 5.0 mustang has a factory "H" pipe in between the 4 cats they put on it, so I don't think Ford ever stopped the practice.    The last customer mustang I worked on was a 65 289 and it also had a factory "H" exhaust on it so I know it at least goes back that far with Ford.

[KurtS]

IIRC, the X-pipe gain has to do with scavenging efficiencies. The charge coming down one pipe helps scavenge the other pipe.
Been a while since I read about these systems, YMMV.

[cook_dw]

IIRC, the X-pipe gain has to do with scavenging efficiencies. The charge coming down one pipe helps scavenge the other pipe.
Been a while since I read about these systems, YMMV.

Correct.  It also allows a smoother transition between the banks and helps draw exhaust from one side to the other (i.e. scavenging).  X-pipe over H but either is better than none.

Quick read.

http://www.superchevy.com/how-to/exhaust/1504-x-and-h-pipes-add-easy-horsepower-but-which-is-best-for-your-ride/