I am looking for a little more rumble exhaust note out of my '72 small block. One catch, i would like to keep it looking stock from behind, any suggestions on mufflers that would give me a good sound?

 

Throw some longtubes on it first it may just sound the way you want.

 

Hmmm, I found that the more HP my car makes, the less noise I want out of it, but in answer to your question, just replacing the stock mufflers with magnaflows or something similar should louden it up.

Note that often louder mufflers do not flow as well as some quality performance mufflers that are quieter, costing you HP.

Doug

 

Hi ms72,
Corvette Central sells 'off-road' mufflers that look just like the stock mufflers, but have fewer baffles in them, so are noticeably louder.
They were an option, (N11), for the 68 model year.
Might be what you're looking for?
Regards,
Alan

 

You could get an aftermarket muffler set, like cherry bombs or for about $400... bucks you can get the under car chambered exhaust system at Ecklers and they have the same sound as the side pipes.

 

More info on our N11 exhaust system can be found here.

 

Well I would get the best, Flowmasters!!!!
All other are just gutted factory knockoffs!!!

 

I got the SS chambered exhaust for my BB from Ecklers. It fit perfect. It'll sound a little different depending on your cam, but I LOVE the sound. Here's my 1st Drive Video w/ sound.
http://www.youtube.com/watch?v=GeP3hvJHR08

 

Tried and true Walker/Dynomax super turbos will outflow the Dronemasters all day in fact so will most aftermarket muffs.
IMO they are crap but yes they sound good until you go tone deaf lol.

Just get what you like for sound though almost anything is better than factory stock stuff. Seriously adding headers will change the tone out the exhaust, give you a little more without totally changing the car.

 

Who says? A magazine doing a muffler test paid for by Dynomax???

 

Lots of manufacturers make turbo type mufflers which were originally developed by GM for turbo charged Corvairs. Very low restriction. They'll give you a nice low rumble putting around, but when you nail it?........Music, haha!
I've used the Walkers on everything since the 70's. And, they're smaller and lighter than the originals. Get the longer ones, i think they're 14in. rather than the 12in, for a deeper tone.

 

there are days when i like quiet.there are times when loud is fun .so for me this is what i am going to do.http://www.youtube.com/watch?NR=1&v=QJ-t094ow-g

 

From elseware on the forum. Flow of various mufflers, measured in CFM:

OEM..................................... ........................................ ...225
Gibson SuperFlow 788200.................................. ............311
TTS Bullet Cat Converter............................... ..................324
Flowmaster 40 series 42540................................... .......352
Flowmaster 50 Series.................................. ...................362
Flowmaster 40 series 43040................................... .......392
Dynomax Super Turbo................................... .................410
Flowmaster 62631................................... .......................435
Carsound Cat Converter............................... ..................436
FLP Cat Converter............................... ............................440
Edelbrock Victor 5535.................................... ..................562
Flowmaster 40 series 435409.................................. ........576
Edelbrock RPM series 5511.................................... ..........579
Flowmaster Delta Force Racing 54040-10........................634
Edelbrock 304 series 5560.................................... ...........640
Edelbrock Gen App 5505.................................... ..............708
Dynomax Race Magnum Welded 17216...........................711
Borla XR-1 40600................................... ..........................836
Borla XR-1 40615................................... ..........................854
Dynomax UltraFlow SS 17263................................... .......1000
Dynomax Race Magnum Welded 17218...........................1000
Borla XR-1 40575................................... ..........................1100
Dynomax UltraFlow............................... ...........................1133
Edelbrock Victor 5537.................................... ..................1400
Borla XR-1 40450................................... ..........................1400
Borla XR-1 40741................................... ..........................1450
Dynomax UltraFlow SS 17296, 17268..............................2200
Dynomax Race Magnum Welded 17220, 17224...............2200
Dynomax Race Magnum Welded 17225...........................2600

The formula for required exhaust flow is: horsepower times 2.2. Pretty simple eh?

So if your car makes 400 hp, you will need a total of 880 cfm muffler capacity for an unrestrictive exhaust system. So for dual exhaust, you would need mufflers that flow 440 cfm.

For reference, a 2.5 inch diameter pipe flows ~500 cfm. Adding non-mandrel bends will lessen that amount.

 

Seriously, If you think the Dynomax super turbo flows 410 CFM
in this pic,
[IMG][/IMG]

And a super 40 Flowmaster only flows 352 CFM in this pic
[IMG][/IMG]

your Fxxxxx in the head! Its as simple as that!

 

Open space has nothing to do with airflow. It's all about smooth and consistant flow. Look at the turns the gas has to make inside the two mufflers.
Dynomax: 2 relitively gentle 180* bends with cruved guides to help the gas around the corner. Chamber volume is also relitively constant, so gas speed is fairly constsiant. The flow is very laminar through a Dynomax. The extra distance is has to travel is no different than having an extra 3' of tailpipe.

Flowmaster: Gas goes into the first chamber and rapidly expands, causing velocity to drop conciderably. Then into the second and it is split against a flat wall that abruptly forces it to change direction with another expansion and velocity drop, then it has to go around another very sharp corner around the back side of the V baffle. Then the two airstreams from around the baffles mash back into each other and make another abrupt 90* into another large volume. The flow is anything but smooth and major vortices are generated and almost every transition point.

If you want to continue to believe Flowmasters advertising hype go right ahead, but others may be interested in why Flowmasters are not, in fact, the masters of flow. I'll get off my soap box now

 

Like the Flowaster sound like most do but after 3 different sets and trying a few pairs of the Dynomax I was sold. THey flat out work


Interesting their 50 series outdo the 40s thought it would be the opposite.


On the 550cfm/2.5" pipe anyone know how long a pipe that references to? Wouldnt it flow less the longer it is?


Bottom line if your car is stock or mildly modified any of those mufflers will pick the power up over stock. Get what sounds good to you.

lol Ok buddy. fxxxx in the head is looking at pics and thinking you know something.


Loud doesnt always equal fast.

 

Any chance the corvette central truck will have these off-road C3 mufflers at carlisle next weekend?

I'll be there with a pocket full of $$$

 

Any more free shipping offers coming up?

 

Actually Walker bought the winning company after losing Hot Rod's first muffler shoot out badly. Despite 3 entries Walker was 9th. 14th & 15th.
The winner was renamed Dynomax.

 

Whatever you all want, just keep buying gutted factory mufflers and thinking your upgrading.