[mikev65]

I have a mild 454. Low compression, xe268 cam in my 65. Right now it’s has 1 7/8 headers w 3 inch pipes going through 2 chamber summit brand mufflers dumped right before the rear axle. It sounds decent but it’s deafening & the drone is terrible at part throttle. Definitely want to put tail pipes on it too. Looking for muffler recommendations to see what you guys had success with. I’d like to take the car out at night without waking up the whole block but I still want it sound nice when I lay into it. I wanna road trip this car too. Thanks

 

[Hotwire]

I have a "similar" setup, cammed low compression 364 (LS 6.0), same size header/exhaust.

Running summit racing 3" system, I tried the summit welded turbo (sounds awesome dumped), summit regular turbo (even better but sounds like crap with tailpipes), now am running Hooker VR304 mufflers. Didn't realize it when I started but the car had mufflers in the wrong spot, not knowing any better I hung the exhaust the same way and it's been ill fitting ever since. I couldn't get summit tailpipes (straight out to rear bumper) to work w/ mufflers in the wrong spot (offset to frame rails instead of driveshaft) so I purchased Flowmaster 15819 tailpipes. Still had to modify them some with my muffler placement, but the tailpipes fit good and helped keep exhaust out of the car.

If you want it quieter I would recommend going with 2.5" tailpipes. Exhaust gases cool down between the engine and tailpipes, so there's less volume when exiting. The smaller pipe helps quiet the exhaust.

welded turbos dumped

welded turbos w/ tailpipes, really "clappy" and loud

summit regular turbos with tailpipes, sound good, but loud

hooker vr304 mufflers, I like them, but loud too
freshly installed, they were quiet and sounded good

Carboned up, they pop and crackle a lot. Noticed a good seat of the pants increase in the upper rpms w/ the straight flow through muffler. Now that they're broke in I'm starting to get some ear ringing after beating on it. Looking to go with a longer case muffler to try and help quiet it down, potentially decreasing tailpipe size too.
1964 Chevelle Malibu running the Roval in Sophia. LQ4, T56, Elgin E1839P cam

 

[Hotwire]

One other thing, if you have access to a welder and are worried about hanging tailpipes, get a handful of Walker 36516 hangers off amazon, makes routing/mounting a breeze. You can tack them on or run a bead of weld, hammer the rod to the pipe, weld, hammer, and you'll end up w/ a J rod like factory exhaust hangers.

 

[bry66]

I'm running 40 series Flowmasters. Long tube headers into 2.5" pipes and tailpipes that exit at the rear bumper. These do drone a little (pretty sure all Flowmaster's do) but not unreasonably so. They scream under WOT and they're still tame enough that I can come & go without pissing off any neighbors.

 

[Alwhite00]

I'm really happy with my magnaflows. No drone and bark pretty good at WOT

 

[chaze]

I'm running 40 series Flowmasters behind 2 1/2 pipes and OEM manifolds on a stock 396. Pleasant sound and no drone.

 

[2/75NastyNewbs]

I just picked up the new Pypes turbo pro mufflers in 3”. If you can wait a couple days, I’m going to try to get a video posted up here. They’re supposed to be pretty quiet. Going to put tail pipes on eventually.

Regardless of what mufflers you choose, tail pipes will mellow it down tremendously. Dutchmax has a few videos floating around here of his dynomax ultraflows with tail pipes. Try to find it. Sounds good

 

[Matt 69]

I am running Dynomax Super Turbo mufflers #17792. They are longer and thicker than other turbo mufflers because they are 3" all the way through the muffler. They sound great with no drone and flow very well for a Turbo muffler.

 

[Kirk's67SS]

I have the same as the guys in Posts # 4 / 6
and agree with Post # 7 that the 2.5" Tail Pipes do keep the Sound Down
until you put the Peddle to the Floor

 

[Bandit1978]

Flow Master 40's stock exhaust manifolds

 

[oliver69]

here is my comparison

 

[CMCE]

If I may, please allow me to make a few suggestions. At your HP level, 3" exhaust is unnecessary, you need around 500hp to see the benefit of a 3" system. A 2.5" system is all you need. Since you will be road tripping this car, do yourself a favor and get a complete 2.5" header-back system with tailpipes and enjoy the trip. You have a choice between X-pipe, H-pipe, or a straight dual system. X is good for some top end, and H for some low end torque. Choose your mufflers wisely- FM 40's can be too loud for some, and they drone. 50's (especially Super 50) are quieter and control drone much better. Straight-through's are generally quieter and flow extremely well, but some have a tendency to drone too. Turbo mufflers tend to be the quietest and control drone the best. Drone occurs around 1800-2300 rpm +/- 100rpm, so if your cruising rpm is in that range then muffler choice becomes critical. There are sound clips here- Classic Muscle Car Exhaust , and feel free to call if you need more info or advise.

 

[CorvZ061]

I'm running Borla ProXS 3" behind my 509. They sound great! not so loud as to get annoying, but you know something is there. They are loud when you're on it. I don't have turn downs or tail pipes at the moment, I get some drone. When I put my tailpipes on I'm betting that drone will go away.

 

[B52bombardier1]

Magnaflows connected to an H pipe with Hooker Blackheart headers up front. No drone and quiet. I almost wish they were a little louder.

Rick

Sent from my SM-G965U using Tapatalk

 

[Monkey]

Summit headers Magnaflow 20" magna flow x pipe dumps at axles. just the perfect note and volume

 

[budsthe3]

I'm running dynomax ultra flows 3in dumped at the rear axle, it has some drone but not too bad. Love the way it sounds. They're practically straight through.

 

[68Chevele]

I had Stupid 40's on the car, why do I call them stupid? well they are super loud, droan all the time and did not make my car any quicker or faster than the small case Delta Flowmasters did, the super 40's are sitting in the corner of the garage now. The car runs just as quick with the cutouts closed or open and it's pretty quiet in the car on the return road with the small case mufflers.

 

[mikev65]

Thank you everyone for the input. Looks like I have a lot of YouTube videos to start watching haha. I know I don’t need a 3 inch exhaust but I’m probably keeping it & reducing it to 2.5 out of tailpipes. Then I’ll add a cutout in the 3 inch section for when I wanna get rowdy. I just paid a shop to do it last summer so I can’t justify scrapping it and replacing 2.5 the whole way. Just gotta find mufflers that are the perfect balance of sounding good when I stomp on it but quiet enough to not have my ears ringing after driving a few hours. Thanks again

 

[67_LS1]

Dynomax long case super turbo mufflers, part 17749.
They make my tiny V6 sound “not horrible”, which is more than I can say for the Flowmaster 50 series or the Walker QuietFlow IIIs.

 

[suntreemcanic]

Get the biggest Walker mufflers you can fit under the car with tail pipes.