Catback performance exhaust - review

[Oaktree]

I've had my Tahoe for about 2 months now, (High Country, 6.2) with the GM/Borla catback exhaust and wanted to post my impressions since a few are probably thinking about it. Short of it, I wouldn't buy it again.

Overall I'm happy with the look, start-up sounds and the growl around town when accelerating. It's very tame when off throttle or maintaining a single speed around town - I would say stock level db. It could be too quiet for some, its that quiet.

My biggest dislike and one that might have me remove it (but I had the dealer throw away the stock one) is the drone at highway speeds, between 65-78mph. Its loud and irritating. Above 80mph it does go away and thats what I did on our last road trip, its that irritating and teh story I was going to tell the police Can you turn up the radio, yes, but it would be loud and if you have kids sleeping, too loud.

I'm not sure what I can do to eliminate the drone. I would not recommend this product.

 

[Baja_Bob]

Does the drone come from the DFM kicking in? On my '16 Silverado you would hear a distinct drone at speed when the engine would go to 4 cylinder mode on the highway, I wonder if the aftermarket exhaust makes the drone more noticeable

 

[mikew2069]

Really surprised to hear the GMP/Borla setup has drone! Kinda sad.... Can you get a db level of the cold start?

 

[NYisles1]

Agree completely. Have same setup on my at4. I wouldn’t say the highway drone is loud but it is there and noticeable- and louder when towing or climbing a slight grade.

 

[Oaktree]

Does the drone come from the DFM kicking in? On my '16 Silverado you would hear a distinct drone at speed when the engine would go to 4 cylinder mode on the highway, I wonder if the aftermarket exhaust makes the drone more noticeable

I don't think so. I'll check again on the next road trip but I hear it all the time at those speeds.

 

[Oaktree]

Really surprised to hear the GMP/Borla setup has drone! Kinda sad.... Can you get a db level of the cold start?

I could shoot a video, but I don't have a db meter.

I'll say my wife's BMW 340 with BMW perf exhaust is much louder and my trackhawk was also louder at start-up - both of the those cars had zero drone and much better sound. That's what makes me so disappointed.

I could shoot a video my wife's car and than the Tahoe for comparison. The Tahoe would not come close to ******* off a neighbor on cold start-up.

 

[mikew2069]

I could shoot a video, but I don't have a db meter.

I'll say my wife's BMW 340 with BMW perf exhaust is much louder and my trackhawk was also louder at start-up - both of the those cars had zero drone and much better sound. That's what makes me so disappointed.

I could shoot a video my wife's car and than the Tahoe for comparison. The Tahoe would not come close to ******* off a neighbor on cold start-up.

That is so disappointing to hear about the drone. I was really leaning towards this system since I think Corsa will be too loud.

When I was doing the exhaust on my X5, I made the video below. I used the app Decibel X and set my phone up about 6 feet away from the rear end before cold start. According to this app, my cold starts average about 96dB.

If you're feeling adventurous, you could download the app and get a reading at cold start.

(I also posted this on the Performance board. Trying to get a dB rating on GM Performance and on the Corsa)
Fast forward to the end for the results...

 

[Baja_Bob]

I was just wondering if that drone sound starts from the engine, exhaust manifolds and just travels out the exhaust.

 

[rdhogg]

I have had my Borla cat-back duals now for about 4 years on my 2013. I never experienced any drone at any speed. I don't know if the 'tune' makes any difference, I have a Diablo Sport tuner, AFM turned off, rev limiter turned off, set the shifting a little more solid, tuned for 93 oct. This all should not make any difference in hearing a drone though. Here is the cold start.

 

[rdhogg]

That is so disappointing to hear about the drone. I was really leaning towards this system since I think Corsa will be too loud.

When I was doing the exhaust on my X5, I made the video below. I used the app Decibel X and set my phone up about 6 feet away from the rear end before cold start. According to this app, my cold starts average about 96dB.

If you're feeling adventurous, you could download the app and get a reading at cold start.

(I also posted this on the Performance board. Trying to get a dB rating on GM Performance and on the Corsa)
Fast forward to the end for the results...

The Borla sounds great, much better than stock. BTW love the custom rims on your Razor scoter , ha.