Which exhaust generates the best power?

**R_Yates69@Hotmail.com** · 08-11-2009, 11:50 AM

The topic speaks for itself, which exhaust generates the most power?

**shady milkman** · 08-11-2009, 12:07 PM

so does the search.......there is not generic best exhaust

the highest flowing/least restrictive exhaust will generate the most power in general.
the size of the pipe almost plays into it

a custom true dual exhaust without mufflers..so straight pipes...will produce the most power.

the question is soooooooooooo open ended there are countless possibilities

**Mr. Luos** · 08-11-2009, 12:09 PM

True duals dumped before the axle.

As for catbacks....they tend to be within a few HP of each other, with the Flowmaster bringing up the rear (for whatever reason).

**Hi-Po** · 08-11-2009, 12:53 PM

Dis agree. True duals make great power.... and sound. But I bet a 4" Mufflex with a nice cat back makes more power. Now, if your talking dumped before the axle, I bet they are close. I would still put my money on the 4" Mufflex or similar style. I could be wrong.

You can go wrong with either really. They will both make great power and sound.

**R_Yates69@Hotmail.com** · 08-11-2009, 03:37 PM

Ok I def worded this wrong, thanks for the help anyways, I think i'll just take this to pms lol

**shady milkman** · 08-12-2009, 04:35 AM

Originally Posted by R_Yates69@Hotmail.com

Ok I def worded this wrong, thanks for the help anyways, I think i'll just take this to pms lol

its all good

**Goat-E** · 08-12-2009, 05:37 AM

An insulated exhaust. The insulation holds the heat in whereby causing the gasses to expand and move faster. This causes more scavenging and better flow. You need to do the math on cross-section and determine delta pressure. 2-5 lbs delta pressure helps to maintain low end torque. I am running a manifold back like this. 2.25 x 2 y'd into a single 3 inch with highflow cats and a straight through muffler before the bumper. There were a lot of physics advantages to this setup. All magnaflow equipment. It all depends on what you want and intend to do. I'm only expecting around 425 hp buy the end of my MOD plans. (This is not a joke shady)

**Firebirdjones** · 08-12-2009, 06:07 AM

If you want a simple 3 inch catback, you can't go wrong with any of them really. They all perform nearly identical. Just pick a sound you can live with and a price you can afford.

If you want better performance than a 3 inch catback then there are a few different routes to go,,,

Start looking at mufflex for a 3 1/2 or 4 inch catback. I vote for the 4 inch,,,best system I've ever tried on a 4th gen.

If you want a real dual system you can custom bend one, or buy a system that dumps in front of the axle, or my personal vote would be to pony up for a Bassani true dual setup.

**Marc 85Z28** · 08-13-2009, 09:59 AM

Originally Posted by Hi-Po

Dis agree. True duals make great power.... and sound. But I bet a 4" Mufflex with a nice cat back makes more power. Now, if your talking dumped before the axle, I bet they are close. I would still put my money on the 4" Mufflex or similar style. I could be wrong.

You can go wrong with either really. They will both make great power and sound.

Maybe the newer Magnaflow Mufflex systems are better, but the Spintech dual out I originally had and then the Flowmaster single out where outrageously heavy, and as I later found out fairly restrictive. The Spintech is terrible! I gained quite a bit by slipping off the catback on the dyno.

I now have 3" duals with single chamber Flowmasters and the power and sound cannot be beat, I don't care what you run. I gained NOTHING by dropping that setup.

Originally Posted by Goat-E

2-5 lbs back pressure helps to maintain low end torque

You're misinformed. I mean, seriously? 2-5 psi backpressure would restrict HUGE amounts of power

**BADASS2000SS** · 08-13-2009, 11:29 AM

Originally Posted by Hi-Po

Dis agree. True duals make great power.... and sound. But I bet a 4" Mufflex with a nice cat back makes more power. Now, if your talking dumped before the axle, I bet they are close. I would still put my money on the 4" Mufflex or similar style. I could be wrong.

You can go wrong with either really. They will both make great power and sound.

I would love to see someone try to fit a 4" exahust under a Camaro!

**Hi-Po** · 08-13-2009, 12:47 PM

Were not talking about TWO 4" pipes. One single. I cant help but think a Camaro underbody is much different then a TA's... but maybe it is. Mine is a fabb'd up piece. Just like Mufflex, just done by someone else by hand.

The SpinTech is fairly restrictive, yes. It sounds good though IMO. But, when talking about certain cat-backs being more restrcitive over another... My 4" electric cutout stops the discussion on my part

Always open.

**Hi-Po** · 08-13-2009, 12:50 PM

And im still trying to figure how one could type such a short, to the point sentence... And a thread title for that matter... and mis word it.

Seems pretty cut and dry to me

**Firebirdjones** · 08-13-2009, 03:14 PM

We found with track testing a 450+ rwhp camaro that the 4 inch mufflex gave the best performance. Didn't matter if we stuck the Spintech or the flowmaster muffler on it.
At the time Magnaflow wasn't in the picture when it came to 4 inch systems. Maybe that muffler is better,,,,but I can't comment for sure.

This was compared to all the 3 inch catback systems we tried that can be store bought and bolted on with simple tools.

Now when you get into dual systems,,,the cards change dramatically. We unfortunately never got to try it on this car,,,the Bassani was too expensive to purchase just for testing, and the owner of this car didn't want a fabbed up system under the car with dual mufflers that would compromise ground clearance, so that was out of the question as well.

**Goat-E** · 08-13-2009, 07:50 PM

Originally Posted by Marc 85Z28

You're misinformed. I mean, seriously? 2-5 psi backpressure would restrict HUGE amounts of power

Did I say anything about horsepower? If you don't keep a minimum amount of resistance your bottom end torque will go to s**t along with your fuel mileage. Daily driving is not wide open throttle and upper RPM's. I researched exhaust design and principle for over 2 months almost daily before deciding on my custom exhaust design. Depending on what your application if you are using the vehicle for a DD there should be some balance. I would like for you to try to tell me that the penultimate setup for street use is open 3 inch headers. That measure is what I found from several sources so if you have a problem with it go argue with them. My exhaust works wonderfully for my application FYI!
I'm running stock manifolds with highflow cats with the 2.25 inch pipes Y'd into a single 3 inch and a Magnaflow 3 inch in/out straight through muffler hung in the insulated recess just before the rear bumper. Does not sound radical at all, nice deep rumble and probably gained near 380 square ft per minute of flow over the stock 2 inch duals while maintaining a slight initial "Delta" (previously back) pressure at the cats.

**BADASS2000SS** · 08-14-2009, 02:53 AM

Originally Posted by Hi-Po

Were not talking about TWO 4" pipes. One single. I cant help but think a Camaro underbody is much different then a TA's... but maybe it is. Mine is a fabb'd up piece. Just like Mufflex, just done by someone else by hand.

The SpinTech is fairly restrictive, yes. It sounds good though IMO. But, when talking about certain cat-backs being more restrcitive over another... My 4" electric cutout stops the discussion on my part

Always open.

I can see one 4 inch pipe making it to the back. It would have to go down the passenger side though. Having a cutout on a single 4 inch pipe has to be badass! I can only imagine the noise that must make! I say "the louder, the better"

**shady milkman** · 08-14-2009, 05:35 AM

Originally Posted by Goat-E

Did I say anything about horsepower? If you don't keep a minimum amount of resistance your bottom end torque will go to s**t along with your fuel mileage. Daily driving is not wide open throttle and upper RPM's. I researched exhaust design and principle for over 2 months almost daily before deciding on my custom exhaust design. Depending on what your application if you are using the vehicle for a DD there should be some balance. I would like for you to try to tell me that the penultimate setup for street use is open 3 inch headers. That measure is what I found from several sources so if you have a problem with it go argue with them. My exhaust works wonderfully for my application FYI!
I'm running stock manifolds with highflow cats with the 2.25 inch pipes Y'd into a single 3 inch and a Magnaflow 3 inch in/out straight through muffler hung in the insulated recess just before the rear bumper. Does not sound radical at all, nice deep rumble and probably gained near 380 square ft per minute of flow over the stock 2 inch duals while maintaining a slight initial backpressure at the cats.

i have issue with you saying you need to keep some sort of backpressure to make power ..i am sure you misspoke and were referring to delta pressure

**Marc 85Z28** · 08-14-2009, 06:49 AM

Originally Posted by Goat-E

I researched exhaust design and principle for over 2 months almost daily before deciding on my custom exhaust design... That measure is what I found from several sources so if you have a problem with it go argue with them.

What sources? Other misinformed people on the internet spreading myths?

What is next? A restrictor in your intake tract to help low end torque too?

You're exhaust works wonderfully for your application? How would you know? You have nothing else to compare it to other than stock.

**Hi-Po** · 08-14-2009, 07:50 AM

Originally Posted by BADASS2000SS

I can see one 4 inch pipe making it to the back. It would have to go down the passenger side though. Having a cutout on a single 4 inch pipe has to be badass! I can only imagine the noise that must make! I say "the louder, the better"

I cant think of any exhuast system I would trade my single 4" custom with single 4" E-DMH cutout for. With that cutout open, its stupid loud. In a good way

**shady milkman** · 08-14-2009, 07:53 AM

Originally Posted by Hi-Po

I cant think of any exhuast system I would trade my single 4" custom with single 4" E-DMH cutout for. With that cutout open, its stupid loud. In a good way

id believe it

**Firebirdjones** · 08-14-2009, 08:40 AM

For those that want to get technical on backpressures and restriction on exhaust systems there is an easy way to test any system.

A simple vacuum gauge attatched to an exhaust bung will tell you how much restriction you really have. Most systems will show 2-3 inches of vacuum, pretty typical. Ideally you want "0"
If you have more than 2-3 inches then you have something choking the motor down and costing HP.