69 cuda with 360 stroked to 410 Way the hell to loud.

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twalt87

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The car was being built to be a drag car, we got it and got it useable for street the exhaust was all already on it.
The car has roughly 600hp, and is using flow master 40 series mufflers. Any mufflers i can easily chuck in there to quiet this thing down? Driving for an hour and your ears ring. You cant have a conversation standing beside it idling.
 
Anything but Flowmasters lol, seriously Magnaflows, or Borla would be my choice. I personally run SpinTech mufflers.
 
Personal preference, but I really like the Borla ProXS. Deep and mellow tone without being obnoxious. Their website claims up to 740 hp before becoming a restriction on a dual 3" system.
 
I ran dynomax super turbos on the 550hp indy sb stroker and found the exact same thing.
I switched to walker quietflow, but I also switched from a sb stroker to a bb stroker. So can't really make an apple comparison.
I am debating switching from 2.5" to 3"
 
Awesome! Thanks for the options and replies. Loud is cool and all but this just isnt enjoyable haha. When I drive to my buddies house he hears me from 2 blocks away
 
Does it have tailpipes on it? If not put some on it, that will definitely make the cabin noise much better.
 
The car was being built to be a drag car, we got it and got it useable for street the exhaust was all already on it.
The car has roughly 600hp, and is using flow master 40 series mufflers. Any mufflers i can easily chuck in there to quiet this thing down? Driving for an hour and your ears ring. You cant have a conversation standing beside it idling.
Is power important on the street? As in, would a loss of 50/75 or better HP while on the street an OK thing?

Here’s the catch to a quiet exhaust, the muffler has to get longer for more sound deadening. Multiple mufflers may be needed for a conversation.

Try this. Glass packs with a large inner diameter, as long as possible, connected to and in front of the mufflers. Done in this order, it will help quite the interior. Glass pack mufflers normally have a very thick case shell that helps contain sound while dampening the exhaust note within.

Turbo mufflers are the quietest but most restrictive of any performance muffler. Having used the dyno max quite flow mufflers before & cutting them open, it’s easy to see where there the quite and power robbing. These mufflers by themselves can be used as a stock replacement muffler.

As above, tail pipes help a lot as well. Chrysler used a resonator in the tail pipe section on many cars for years. My ‘74 Duster had one, my ‘18 Ram has one. At the end of the tail pipe creates a quieter sound at the end of the system for the outside people, not inside. This is why I suggested glass packs before and connected to the front of the muffler.

Again. Glass packs and mufflers should be as long as possible.

Best of luck on your attempts.
 
Some of the welded Dynomax Ultras flow more than an open pipe. I know. Sounds impossible. It's alien technology. They have charts on their website.

and......I caint resist. Too loud? Ya sissie. lol
 
It has tailpipes, I don't care about losing a few hp, if I have to add mufflers with resonators I will.

As for the too loud joke lol. It may as well be open headers right now lol.
 
I still trying to get over no pictures, not a one of a 69’ cuda with a 600hp small block.
That’s like giving a Playboy to a guy on death row with no pictures. LMAO.
 
Cross overs (H, or X, your choice) and the largest/longest Mufflers you can fit and afford. Go as large as possible on the pipe diameter as you can fit or afford too.
Auto Exhaust Science

Power impact can be minimized, but most folks go too small or try to pinch pennies a bit too much and then lose big power. Quieting something doesn't need to rob power, it can still flow (and flow it must), the idea is to reflect some of the energy and reduce the sound pressure which is why larger diameter pipes can help - deepens the tone and kills some of the rasp, pop, and harshness.

Dynomax makes some great stuff and others have recommended same or similar above.
 
Awesome! Thanks for the options and replies. Loud is cool and all but this just isnt enjoyable haha. When I drive to my buddies house he hears me from 2 blocks away
Only 2 blocks? sounds to quiet to me.
If I'm not rattling windows from 2 blocks away I'm down on power.
 
What size are the inlet and outlet of those flowmaster 40’s? I’m lookin for a set with 3” inlet and outlet. Lol

I like loud.
 
Listen to the stereo while parked with the car shut off. While driving wear ear plugs and use sign language to communicate with your passengers. You bought a race car not a Limo.
 
I loved the glass packs on my car. I would play the beat of the camshaft on the steering wheel at stop signs. No better music on a crisp summer night. Volume control was the accelerator pedal.
 
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