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Why do they call this true dual exhaust? by 2.5
Started on: 09-17-2014 10:53 AM
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Last post by: Jake_Dragon on 10-12-2020 05:09 PM
2.5
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Report this Post09-17-2014 10:53 AM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
Just an example.


Why is this type of exhaust called true dual? To me... for it to be true dual, the exhaust from one head cannot be merged into the exhaust from the other head. There would also need to be two separate mufflers.
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Report this Post09-17-2014 10:58 AM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post

2.5

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This to me is true dual. (Though for a V8)


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Report this Post09-17-2014 11:01 AM Click Here to See the Profile for dobeySend a Private Message to dobeyEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by 2.5:

Just an example.

Why is this type of exhaust called true dual? To me... for it to be true dual, the exhaust from one head cannot be merged into the exhaust from the other head. There would also need to be two separate mufflers.


It's not called true dual. Anyone who calls it that is wrong.

It is simply called dual outlet exhaust (or simplified to "dual" which could refer to dual outlet or a true dual setup).

True dual doesn't necessarily mean that the heads are independent. 180 degree headers for example, have a couple of ports crossing to the other side, but there is no intermixing of gases, after the primary collectors.
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Report this Post09-17-2014 01:07 PM Click Here to See the Profile for Formula88Send a Private Message to Formula88Edit/Delete MessageReply w/QuoteDirect Link to This Post
Because "they" either don't know what true dual exhaust is or "they" lie.

True dual uses a completely separate pipe path for each half of the engine. There may be a H-Pipe or X-Pipe to even out exhaust pulses, but that's all.
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Report this Post09-17-2014 04:56 PM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by 2.5:

Why do they call this true dual exhaust?


Who is this "they" that you are referring to? Stay clear of them.
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Report this Post09-17-2014 05:28 PM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
Thanks for confirming my thoughts
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Report this Post09-17-2014 06:48 PM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post
I don't care what "they" call it. This type of 3" in and dual 2 1/2" outs from a crossflow muffler works well on 3800 engines. BTW, who is the OP referring to as "they"?

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
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" ON THE LOOSE WITHOUT THE JUICE "

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Report this Post09-17-2014 08:24 PM Click Here to See the Profile for hyperv6Send a Private Message to hyperv6Edit/Delete MessageReply w/QuoteDirect Link to This Post
Keep in mind one exception. Flowmaster makes an exhaust for a Camaro that has two pipes back into one cross flow muffler and two exhaust pipes. The trick is the muffler houses two separate mufflers in one housing. So while it looks like a single muffler cross flow it really is a duel. I have seen it from other companies do similar things on rare occasions. Not common but something to watch for in some rare cases.
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Report this Post09-17-2014 08:31 PM Click Here to See the Profile for cyrus88Send a Private Message to cyrus88Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Dennis LaGrua:

I don't care what "they" call it. This type of 3" in and dual 2 1/2" outs from a crossflow muffler works well on 3800 engines. BTW, who is the OP referring to as "they"?



Nobody knows!
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Report this Post09-17-2014 09:27 PM Click Here to See the Profile for DKcustomsSend a Private Message to DKcustomsEdit/Delete MessageReply w/QuoteDirect Link to This Post
Exactly.
Thanks for making this thread.

I, however, will be doing a True dual exhaust on my Fiero, each header will have its own exhaust system and come out a separate side of the car
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Report this Post09-17-2014 11:15 PM Click Here to See the Profile for dobeySend a Private Message to dobeyEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by hyperv6:

Keep in mind one exception. Flowmaster makes an exhaust for a Camaro that has two pipes back into one cross flow muffler and two exhaust pipes. The trick is the muffler houses two separate mufflers in one housing. So while it looks like a single muffler cross flow it really is a duel. I have seen it from other companies do similar things on rare occasions. Not common but something to watch for in some rare cases.


Not that uncommon at all. It's a pretty common muffler type to install on trucks.
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Report this Post09-18-2014 01:15 AM Click Here to See the Profile for JohnWPBClick Here to visit JohnWPB's HomePageSend a Private Message to JohnWPBEdit/Delete MessageReply w/QuoteDirect Link to This Post
I actually have quad exhaust on my stock Fiero.... I know this because I can stand behind my car and see 4 exhaust tips!

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Report this Post09-18-2014 09:04 AM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by cyrus88:


Nobody knows!


Just random people on forums and in real life. You know "them"
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Report this Post09-18-2014 09:05 AM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post

2.5

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quote
Originally posted by JohnWPB:

I actually have quad exhaust on my stock Fiero.... I know this because I can stand behind my car and see 4 exhaust tips!




Wooo doggies! Octo exhaust!

[This message has been edited by 2.5 (edited 09-18-2014).]

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Report this Post09-18-2014 09:24 AM Click Here to See the Profile for Lambo nutSend a Private Message to Lambo nutEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by hyperv6:

Keep in mind one exception. Flowmaster makes an exhaust for a Camaro that has two pipes back into one cross flow muffler and two exhaust pipes. The trick is the muffler houses two separate mufflers in one housing. So while it looks like a single muffler cross flow it really is a duel. I have seen it from other companies do similar things on rare occasions. Not common but something to watch for in some rare cases.


Also keep in mind "X pipes" where the two exhaust pipes from the engine are merged into one then separated to give two paths again to balance the tone.

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Report this Post09-18-2014 09:31 AM Click Here to See the Profile for mental flossSend a Private Message to mental flossEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Dennis LaGrua:

I don't care what "they" call it. This type of 3" in and dual 2 1/2" outs from a crossflow muffler works well on 3800 engines.



It's a sound principle ar-ar. Doubling a pipes size quadruples the flow capacity. So 2-1/2" should be plenty for the 3 inch.
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Report this Post09-18-2014 02:05 PM Click Here to See the Profile for darkhorizonSend a Private Message to darkhorizonEdit/Delete MessageReply w/QuoteDirect Link to This Post
The exbaust in question is by definition no more or less "true dual" than any exhaust that combines the exhaust at any point. A xpipe or an h pipe would just be "more dual" exhaust than that one... and comoletely pointless
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Report this Post09-18-2014 06:23 PM Click Here to See the Profile for hyperv6Send a Private Message to hyperv6Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by dobey:


Not that uncommon at all. It's a pretty common muffler type to install on trucks.


What truck and who makes it?
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Report this Post09-18-2014 06:26 PM Click Here to See the Profile for hyperv6Send a Private Message to hyperv6Edit/Delete MessageReply w/QuoteDirect Link to This Post

hyperv6

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Generally single in cross flow mufflers with two exit pipes are not good for flow. The F body system loses between 7-10 HP on the 4th gen cars with two tail pipes on each side. It would not be suprising if a single in and out Fiero may have better flow if done correctly. The path of the gas is important as every turn slows it down .
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Report this Post09-18-2014 11:54 PM Click Here to See the Profile for dobeySend a Private Message to dobeyEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by hyperv6:
What truck and who makes it?


Lots of trucks. Dual in/out mufflers are common on trucks as the exhaust routes down one side of the truck, and conversion to dual exhaust is one of the first things many do when buying a new truck.

Not OEM, but similar mufflers get installed plenty.
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Report this Post09-19-2014 06:46 AM Click Here to See the Profile for hyperv6Send a Private Message to hyperv6Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by dobey:


Lots of trucks. Dual in/out mufflers are common on trucks as the exhaust routes down one side of the truck, and conversion to dual exhaust is one of the first things many do when buying a new truck.

Not OEM, but similar mufflers get installed plenty.


I think you missed what I said.

The Flow master system is one muffler but houses to separate muffler in one housing. It is true two pipes back into one muffler but neither side is connected internally and then two pipes back.

The truck system are generally one pipe or two pipes in and two pipes out but only one muffler is in the housing and they just rely on larger muffler with more flow then just use two pipes in the back for looks.

I work in the performance industry and deal with all the large MFG and I know of no other system like the Flowmaster F body system. I am sure there may be one or two others out there but I cannot recall any. None of the trucks are done the same.

Also they often will use the two pipes as it is easier to do than the one large pipe some systems have. Trucks are one of the toughest fits anymore for exhaust due to space limitations of the fuel tank, four wheel drive systems and spare tire.
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Report this Post09-19-2014 07:38 AM Click Here to See the Profile for cam-a-lotSend a Private Message to cam-a-lotEdit/Delete MessageReply w/QuoteDirect Link to This Post
Nobody calls that a true dual exhaust.
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Report this Post10-07-2020 09:58 PM Click Here to See the Profile for GetafixClick Here to Email GetafixSend a Private Message to GetafixEdit/Delete MessageReply w/QuoteDirect Link to This Post
My Fiero with L32 (Series III supercharged with 4T65e HD) has a true-dual exhaust system. The Fiero 60V6 and related engines are 'even fire' so no crossover is required. That is also true of the L32 3800SC engine. The first photo is of the true-dual exhaust system that I designed, and fabricated with the help of a couple friends. That was an equal length extractor exhaust with two custom-spec SpinTech mufflers on 3.4 Pontiac Montana engine with 4T60 transmission. Trunk was not cut. That engine was from a salvage yard, turned out to have a crack in the block at #5, so died after only 4000 miles or so in my Fiero. I located the L32 drivetrain, and the true-dual exhaust was modified to fit West Coast Fiero's flanges. The original SpinTech mufflers, outpipes, and Monza Pacesetter tips were used. Trunk was not cut, everything fits within the original engine bay. The second photo is of that setup before installation into my Fiero. Current project on my Fiero can be found on this link:

http://www.fiero.nl/forum/F...-8mW_OKRh20#lastpost




We are also in the process of having polycarbonate GT sails with scoop made.

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Report this Post10-07-2020 11:11 PM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post

Pictures are.... nice... but we want to hear that bad boy.
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Report this Post10-09-2020 03:52 AM Click Here to See the Profile for AustralianClick Here to visit Australian's HomePageClick Here to Email AustralianSend a Private Message to AustralianEdit/Delete MessageReply w/QuoteDirect Link to This Post
If it was a Mercedes exhaust it would have one pipe and some plastic exhaust tips to do nothing so yes fake dual exhaust gets way worse than that.
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Report this Post10-09-2020 02:28 PM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Australian:

If it was a Mercedes exhaust it would have...




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Report this Post10-09-2020 02:43 PM Click Here to See the Profile for BlacktreeClick Here to visit Blacktree's HomePageClick Here to Email BlacktreeSend a Private Message to BlacktreeEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Getafix: The Fiero 60V6 and related engines are 'even fire' so no crossover is required. That is also true of the L32 3800SC engine.

Yep! This is true for any engine with an even firing order.
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Report this Post10-09-2020 07:02 PM Click Here to See the Profile for cvxjetClick Here to Email cvxjetSend a Private Message to cvxjetEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by 2.5:


Just random people on forums and in real life. You know "them"

Hmmmmmm......."Them!!!!!"

[This message has been edited by cvxjet (edited 10-09-2020).]

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Report this Post10-10-2020 02:47 AM Click Here to See the Profile for AustralianClick Here to visit Australian's HomePageClick Here to Email AustralianSend a Private Message to AustralianEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Patrick:




Worse than the new cars hahaha
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Report this Post10-11-2020 04:25 PM Click Here to See the Profile for Jake_DragonSend a Private Message to Jake_DragonEdit/Delete MessageReply w/QuoteDirect Link to This Post
My V8 Fiero had true dual exhaust. Would a cross over pipe even help in such a short exhaust? I have had several cars that with true dual exhaust. With and without a cross over.
End of the day its what works best on the engine you are installing and what performance you are looking for.

But as a back yard mechanic I never had the money to test the differences I did as much research as I could and in the end went with what my personal preferences are. Mostly loud and a nice thump.

[This message has been edited by Jake_Dragon (edited 10-11-2020).]

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Report this Post10-11-2020 04:48 PM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Jake_Dragon:

...went with what my personal preferences are. Mostly loud and a nice thump.


For a street driven car, my preferences are the same. I'm not trying to gain the last elusive bit of horsepower (which I'll rarely ever make use of). I want an exhaust system that I enjoy the sound of the whole time I'm driving the car... and IMO, that's without an exhaust crossover pipe.
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Report this Post10-11-2020 05:20 PM Click Here to See the Profile for Jake_DragonSend a Private Message to Jake_DragonEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Patrick:

For a street driven car, my preferences are the same. I'm not trying to gain the last elusive bit of horsepower (which I'll rarely ever make use of). I want an exhaust system that I enjoy the sound of the whole time I'm driving the car... and IMO, that's without an exhaust crossover pipe.


I agree but there are exceptions. I had a corvette with true dual exhaust and side pipes and its could have used a cross pipe.
That uneven sound when standing on one side or the other just needed balanced. Now if it would have exited out the back of the car you wouldn't have noticed it as much.
But damn it was a fun car. Just like the Fiero it was like driving a single car parade.
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Report this Post10-11-2020 05:44 PM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Jake_Dragon:

I had a corvette with true dual exhaust and side pipes and its could have used a cross pipe. That uneven sound when standing on one side or the other just needed balanced. Now if it would have exited out the back of the car you wouldn't have noticed it as much.


Well, of course I don't know what your Corvette sounded like... but my nicest car was a big block 4-speed '67 ChevelleSS396 with solid lifters, lumpy cam, hi-rise aluminum intake, long tube headers, "turbo" mufflers, and 2-1/2" tailpipes that exited out the side of the car in front of the rear wheels. No exhaust crossover pipe whatsoever. I loved the rumble of the lopey idle and of the deep roar produced when the 4-barrel Holley opened up under load. That car sounded like.... heaven. It was simply glorious!

[This message has been edited by Patrick (edited 10-11-2020).]

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Report this Post10-12-2020 05:09 PM Click Here to See the Profile for Jake_DragonSend a Private Message to Jake_DragonEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Patrick:

Well, of course I don't know what your Corvette sounded like... but my nicest car was a big block 4-speed '67 ChevelleSS396 with solid lifters, lumpy cam, hi-rise aluminum intake, long tube headers, "turbo" mufflers, and 2-1/2" tailpipes that exited out the side of the car in front of the rear wheels. No exhaust crossover pipe whatsoever. I loved the rumble of the lopey idle and of the deep roar produced when the 4-barrel Holley opened up under load. That car sounded like.... heaven. It was simply glorious!



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