Refining and quieting a loud exhaust system

**MosportGreen66** · #1 10-23-2024, 07:00 PM

Hi Guys,

I'm helping a friend spec a protouring car and after driving a comparable model, he mentioned it is too loud for him/family. Does anyone have experience refining and quieting an exhaust system?

The car is running a new coyote Ford crate engine. It will be used a weekend cruiser/never raced. Performance loss is not a concern and likely won't be noticed.

I'm considering a couple baffles and muffler combination but would appreciate feedback on type/style/brand.

Thanks,
Dan

**Derek69SS** · #2 10-23-2024, 07:51 PM

I'm a big fan of the Pypes "Race Pro" that I have on my LS swapped Chevelle. Very smooth sound, no drone, 3" with X-pipe, and dumps before the rear axle.

LS engines don't have quite the shriek of a Coyote, though.

**Too Many Projects** · #3 10-23-2024, 09:02 PM

I have Race Pro's on my Camaro and they are about as quiet as I want for normal driving. Step on the pedal hard and they are going to let everyone in a wider area know that the car is around...

On my '38, it came to me with unknown mufflers and the wife complained it was too loud. We have used the car to pull the camper and it was rather annoying after a few hours and down right aggravating after 10 hours. After reading way too many reviews about mufflers, I changed them out for Dynomax Super Turbo's that MOST of the reviews said were too quiet on their muscle cars, not enough growl.. LOL They were quieter than I expected and I'm happy with them, but the noise analyst still wasn't entirely happy, but doesn't say much anymore.

**napa68** · #4 10-23-2024, 10:26 PM

Dan,

The Ford Coyote engine are known to be really have a lot of rap (as are the LS engines). Stainless exhaust tends to exaggerate it as well. I see Roadster Shop is using resonance chambers on many of their builds now.

**Arrowsmith** · #5 10-24-2024, 01:39 AM

I used bullet resonators before the mufflers and dB killing cones in the reducers on my 565 cid Nova. Worked great.

**MosportGreen66** · #6 10-24-2024, 03:39 AM

This is great info guys thanks!

**JRSully** · #7 10-24-2024, 12:05 PM

X2 on the Pypes Race Flow. Have had it on a stock L78 Nova for years, I use the Transverse Muffler mounted in the stock location and configuration. it is really pretty quiet at idle and normal driving, but jump on it, and it roars. Best of both worlds IMO

The Following 2 Users Say Thank You to Derek69SS For This Useful Post:
dykstra (10-25-2024), MosportGreen66 (10-24-2024)

The Following User Says Thank You to Too Many Projects For This Useful Post:
MosportGreen66 (10-24-2024)

The Following User Says Thank You to napa68 For This Useful Post:
MosportGreen66 (10-24-2024)

The Following 2 Users Say Thank You to Arrowsmith For This Useful Post:
MosportGreen66 (10-24-2024), olredalert (10-24-2024)