Need a little exhaust advice...

medic717 · February 11, 2016

I bought a GM Performance Muffler from Borla and I'm all set to get it welded in tomorrow. Question is do I remove the factory resonator thats at the back or just do a muffler swap only?

Lgetz · February 12, 2016

If you do any kind of towing or on the highway very much I would leave the resonator on. Without it you will get the dreaded "helicopter sound" when in 4 cylinder mode and the drone at 65-75 mph may be too much to bear.

medic717 · February 12, 2016

If you do any kind of towing or on the highway very much I would leave the resonator on. Without it you will get the dreaded "helicopter sound" when in 4 cylinder mode and the drone at 65-75 mph may be too much to bear.

That's what I'm leaning towards... I tow a little not a ton but I drive about 60 miles hwy to work. I guess my thoughts are I can always have it removed later if I change my mind... I wonder if the resonator will impede flow much tho. I hate to kill what HP gains I could get from the muffler.

beast 10 · February 12, 2016

I would say leave the resonator on , I did a straight pipe with afm valve and resonator in and can here a slight chopper sound, I doubt we gain any significant HP gains from exhaust just sound.

1300c · February 12, 2016

That's what I'm leaning towards... I tow a little not a ton but I drive about 60 miles hwy to work. I guess my thoughts are I can always have it removed later if I change my mind... I wonder if the resonator will impede flow much tho. I hate to kill what HP gains I could get from the muffler.

From what I've read the resonator is a straight through design so it shouldn't hurt anything enough to matter imo. If you're worried about drone, you can leave the flapper valve in the exhaust too.

medic717 · February 12, 2016

I would say leave the resonator on , I did a straight pipe with afm valve and resonator in and can here a slight chopper sound, I doubt we gain any significant HP gains from exhaust just sound.

True or false I'm not sure but Borla listed at 15 percent power increase from their straight thru muffler like I have... could be a misquote on my part I will try to find the page I read that from...

medic717 · February 12, 2016

From what I've read the resonator is a straight through design so it shouldn't hurt anything enough to matter imo. If you're worried about drone, you can leave the flapper valve in the exhaust too.

I'm pretty sure this is what I'm gonna do... leave both and see what I think I can always do more later if I'm not happy with it...

Johnnynovo · February 12, 2016

I bought the same muffler last week. I have it clamped in for now and have been contemplating the same thing. I clamped in a straight pipe in place of the muffler just to see how that compared to the Borla. It had the same sound just with a more noticeable v4 change. I also played with clamping the flapper open and that made no noticeable difference on my truck. The last thing I was wondering was the resonator. I can't imagine it makes that much of a difference since it's so far back (behind the rear wheels). I'm leaning towards taking mine off and having my shop just put new 3" back from the muffler with nice tips.

1300c · February 13, 2016

In the modification section of this forum in the Borla vs muffler delete thread the OP posted some really good quality videos of the muffler delete (headphones are best.) Since the sound is very close to the Borla it might be helpful.

medic717 · February 13, 2016

In the modification section of this forum in the Borla vs muffler delete thread the OP posted some really good quality videos of the muffler delete (headphones are best.) Since the sound is very close to the Borla it might be helpful.

I did read that and you are correct it was very informative! I ended up going with the borla gm performance touring muffler with the resonator delete dumped over the rear axle. I tried to leave the resonator but it sounded stock. Couldn't be happier with it at the moment but I need some more driving time to get a better idea of what it sounds like. It's pretty tame I'm hoping it gets a little louder as it breaks in.... also I tow a decent amount and I wanna see what it sounds like with a load behind it. Thanks for the info!

1300c · February 13, 2016

Every muffler I've had got louder so I would think it would get louder. Post some videos. We're exhaust junkies lol.

medic717 · February 13, 2016

I will try to get a good quality video posted with muffler information for those who may like to sound.

TJay74 · February 14, 2016

I have been running with a Magnaflow muffler, no exhaust valve and no resonator for almost 2 years. Truck sounds good, no drone at all ever. the first round I did the muffler and the exhaust valve and it was still too quiet, then I had the resonator cut out and it was almost perfect.

I am repeating this setup on the new truck, only slight mod may be that I cut out the 3rd cat as well.

UrbanRage · February 14, 2016

I have been running with a Magnaflow muffler, no exhaust valve and no resonator for almost 2 years. Truck sounds good, no drone at all ever. the first round I did the muffler and the exhaust valve and it was still too quiet, then I had the resonator cut out and it was almost perfect.

I am repeating this setup on the new truck, only slight mod may be that I cut out the 3rd cat as well

What are you running the 14" or 18"?

medic717 · February 15, 2016

I have been running with a Magnaflow muffler, no exhaust valve and no resonator for almost 2 years. Truck sounds good, no drone at all ever. the first round I did the muffler and the exhaust valve and it was still too quiet, then I had the resonator cut out and it was almost perfect.

I am repeating this setup on the new truck, only slight mod may be that I cut out the 3rd cat as well.

Mine seems to have gotten deeper but I may decide to remove the third cat as well if it don't get as loud as I would like