[greenie-reddy]

Ok, I'll try to keep this simple. We have a '69 Firebird with a 350 that someone converted to a 4BBL carb. It has a TH-350 and runs great. It has a pretty restrictive dual exhaust with 2-inch pipe and the typical street mufflers. Inside you can barely hear the motor; standing behind the car it sounds loud- but nothing your mother would get too upset about. It has the original exhaust manifolds. OK, we are going to use Pypes 2.5-inch downpipes and convert the entire system to 2.5-inch. We are going to keep dual mufflers (in front of the rear axle- nothing behind). Here (finally) is the question: We would like to hear the engine from inside the car; but don't want to wear ear-plugs either. On occassion we actually listen to the stock radio. It seems we have 2 basic choices: The Flowmaster 40-style mufflers with the "v" shaped baffles; or the magnaflow style with the straight thru "perforated tube" design. Opinions? Thanks.

[android 211]

2 1/2 inch might be a little much for a 350. 2 1/4 would probably be fine for a mild 350. If I'm reading you right you're going to use dump tubes in front of the rear axle, no tailpipes? I would counsel against that. At times you will smell exhaust inside the car and it makes for a noisy interior ride. Search for the Jim Hand muffler test. it was done several years ago (maybe 10) but I've seen it since online. If you want that Pontiac 'gurgle', don't use a H pipe or an X pipe. Firebirds are supposed to have tailpipes that dump just behind the rear wheels, not out the back like a Camaro. I don't like noise, I like my top rated for quiet and power Dynomaxes.

[Formula8]

Well my car would have come with pipes that went out the back. Otherwise I totally agree, complete the system with tail pipes.

Anyway, I have Magnaflows on my car now with a 2.5" X pipe header back and could not be happier with the sound. There is no comparison between an all stainless muffler and a Flowmaster. That being said, it sounds like you are looking for something louder then what I have. I just installed a set of Pypes violators and 4.11 gears on a friends 4.6 Mustang GT and talk about an attitude adjustment!!! The car went from a total creampuff to straight up bad ass at all throttle positions but drones a bit on the highway. They are 409 stainless, lightweight, available from the same guys who made your exhaust in the first place and reasonably priced. IMO, the Violators sound like they would fit the bill. I would rate the noise level slightly less than a Flowmaster but very unique and certainly aggressive.

[Kokamo]

I'd be willing to bet you will regret dumps before the axle unless if comes out the side of the car. You will have exhaust inside the car immediately and the drone would be intense. Done it on my 69 Camaro and it's just like the Bird. It really needs to go over the axle and out the back. I have used Flows all my life and I just like the chambered sound of them. I actually tried a different muffler recently that I like better called the 50 series "Big Block". They are the quietest muffler Flowmaster makes as they are designed for SUV's and trucks....it's a rather large muffler, but if you can fit it, it has one of the best sounds I've heard out of a muscle car. Fairly quiet but well more than loud enough to hear inside. I have them angled out pointing somewhat downward on my Camaro and strait out the back on the 69 GTO. Both of them you can hear the exhaust very well from inside the car with or without the windows down.....and no drone or exhaust inside the car! I agree about the 2-1/2" pipes. If it's a stock motor, then there is no need. Besides, I'm almost certain your manifolds aren't much bigger than 2-1/4 anyway. The only way to benefit from a larger pipe is AFTER the muffler. If you have a smaller pipe, it tends to give you a higher pitch raspy sound in the upper RPM's. If you go larger, it keeps the same sound throughout the RPM range...just so much better in my opinion.

Good luck with it!

~Joe

[Blued and Painted]

The opening on the log manifolds is around 1 3/4 to 1 7/8 inch. With a carbide burr you can open it up to around 2 inches. Ware saftey glasses. The tail pipes will not hurt preformance. As exhaust gasses cool they take up less space. If it's a saterday night cruiser by all means get the loud mufflers. If it's a daily driver with substantial miles driven, then i might suggest the dynomax turbo muffler. IMO.

[greenie-reddy]

Sorry about the confusion. It will have conventional tailpipes. I just want opinions on the sound qualities of the magnaflow vs. the flowmaster. Thanks!

[tolerico]

I would say look into Spintech mufflers. Great sounding. Or Magnaflow over Flowmaster anyday. Flowmasters are too tinny and chebby sounding IMHO.

[chrisp]

Flowmaster’s Delta Flow 40 Series two chamber have them on my 68 bird , no interior resonance at all , http://www.flowmastermufflers.com/?page_id=11139

[tom s]

Take a look at Hushpowers by Flomaster.I had them on my 69 RamAir V 69 bird and loved them.I now have them on my 63 421Lemans.Way better than the 2 chamber flomasters I replaced them with.I can actually listen to my radio now without it blasting.

[Formula8]

Originally Posted by greenie-reddy

Sorry about the confusion. It will have conventional tailpipes. I just want opinions on the sound qualities of the magnaflow vs. the flowmaster. Thanks!

Sorry but IMO, those are two mufflers that are not going to be comparable in sound level or quality. Flowmaster has some new product out there but their basic muffler has a unique sound at idle that you either love or hate. A sound cruising that you love or hate and a full throttle sound is pretty universally loved. With a Magnaflow, it is going to sound healthy but universally liked at idle, universally liked at cruise and universally liked at full throttle.

It's kinda' like who is the better athlete? A champion MMA fighter or the guy who won the gold in the triathlon?

[GTOLou]

Big fan of the magnaflows - I've got a couple of cars w/ turndowns and have not had issues w/ that either.

[crazycarlo]

Muffler and exhaust setup is such a personal choice. The best advice I can give is to go to youtube and look at different videos of them preferbly on the same car/engine as yours.

[greenie-reddy]

It's done. Used pypes ss downpipes and magnafow mufflers- with tailpipes routed in the typical fashion. The shop I used tig welded everything except the tailpipes and it hangs nicely above the e-brake cables. No squeaks or rattles. The sound is fairly agressive under full throttle, but barely audible inside at cruising speed. It doesn't have that flowmaster warble- but it does have a more typical exhaust note you'd expect from a Pontiac. First time I've ever let someone else hang an exhaust system for me- and I didn't miss beating on it while the car is perched on jack stands. Not even a little.

[crazycarlo]

Awesome man got any videos if it? I thought about putting the magna flow magna packs on my mustang.

[Formula8]

Cool, I hope you are as happy with the sound of Magnaflows as I am.