The sound of mufflers? --Dynomax

[SteveInOakland]

I'm going to put a Dynomax Super Turbo muffler on my '73. It has the stock exhaust, but with the pre-muffler/resonator swapped out for straight pipe (nice improvement).

I'm trying to choose between 2" and 2-1/4" for the muffler; both larger than the stock, I realize.

My friend Beandip has been helping me with this but I'd also like to see what others think, and maybe Gary has more to say now.

The amount of noise -- stock muffler vs. 2" Dynomax vs. 2-1/4" Dynomax -- anybody care to estimate the differences?

Like, say, 1.5X louder than stock, 1.8X etc?

Thanks!

Steve

[sblake01]

I have that muffler on my 78. To me it only seems louder than stock when you get on it. My car does have a catalytic converter so I don't know how much effect that has on the sound. Maybe about 1.8 to 2X.

[jmark]

I suspect you'll end up putting on a premuffler. It is loud. Do a search here.

[Montezuma]

I have the Dynomax on both my 78 and 73. I have 2 1/4 pipe on both cars. I originally went without the resonator on my 73 but took it back to my favorite muffler shop two weeks later to have them put it in. The car was 2X as loud. I like it so much better now than before I had the resonator placed in. My 78 has a free flow cat on and along with the dynomax sounds great. I love the sound of my cars with the Dynomax. I get all my systems at Ed Hanson's here in San Diego.

[nateroszhart]

I have the dynomax super turbo muffler on my 280 with straight 2.5" pipe back from the headers and it is plenty loud. Probably a bit too loud, but it sounds really good. Good low pitch at idle.

[Pop's Z]

FWIW, I had a new exhaust system built locally for my 73 stock Z. I used 2- 1/4" aluminized pipe and a Dynomax ROUND super turbo muffler part#17 741. It looks almost like the stock muffler(dimensions:14"X6"...19" total). When I first had the system done I had them put in a 20" glasspac(reversed for better flow) for resonance, but had it removed as the system was too quiet,almost like stock. It sounds much better now, but is not at all loud...just right for me and no resonance. I also had them weld in a flange up front so the system could be removed for suspension work, etc. I'm very happy with the system. It cost about $200 and is nicely tucked up underneath the car...in the same plce as the old system.

Cheers, Mike

[byunique]

Yeah, its going to start sounding like a real sportscar, and to me that made the real difference between stock and Dynomax.... you will certainly like it the sound. I did a 2.5 inch straight back into the Dynomax and had a bunch of resonance around 3000rpms, it would certainly help with a center mufller to reduce that, and cut back the sound a bit...probably your best bet.

[280~Master]

The sound of your Z is up to you. You could go silent just to wizz off the ricers or you could go loud just to wizz of the ricers. If you do the right combo you can get silent with good performance or go loud with good performance.

I myself like it loud. I just put a little insulation in the back and turn the radio up. I have straight 1 ½’ pipe with no resonator and bumpers taken off. You would be surprised to see how many people look at the car when it’s loud. Plus the ricers don’t know what to do when a car is louder than theirs is. You have to sit down and decide what type of sound you want out of your Z.

I have been told to use 2 ½ inch pipe for the L28 with a nice type of turbo Muffler. This should get you some pep in your car. If you have the L24 to L26 I would stay 2 ¼ and use a nice turbo muffler with no resonator. If you have the L28 I would go with 2 ½ no resonator and nice turbo muffler. You just got to remember the muffler will sound good only when you get on it. If you want it to sound good when you sit at a red light then go with no muffler and straight pipe.

[4381821]

I purchased the MSA 2 1/2" aluminum exhaust package, that includes a dynomax turbo muffler, to go with their 6-1 header and I was VERY disappointed with it. Even on my L28 motor, it sounds terrible. The ricer-rony drone had me wanting to pull my hair out every time I hit the acceleration a bit.

I ended up taking it to a local shop, and he cut out a chunk of the mid and welded me in a resonator, which took the "drone" noise out in 2-3500 rpm range.

I would go even smaller next time with 2 1/4" and a resonator. The HP tradeoff ( negligible ), is worthwhile if you drive the car alot. But there's no way I'd put the stock system back on, since the cast iron header was cracked and worthless. I'd say the 2.5" system is easily 2-3X louder than stock.