Experience With Gm Performance Exhaust On Nbs Silverado

5.3Avalanche · July 12, 2007

Hey guys,

I have a 2008 5.3L, Z60, 4x4, extended cab Silverado on order and was hoping to put on a GM Performance exhaust right from the dealer so that I can put it in with my truck payments. I've contacted Borla & Corsa and both have confirmed that Borla does indeed produce these systems for General Motors. I have a few questions that I've emailed to both GM Accessories and Borla but neither have emailed me back with answers.

What does the system look like? Is it accurate to say that it looks exactly as shown on GM's website, since I know they aren't the best at updating pictures there. The picture immediately below is off of GM's site for the exhaust. The next two pictures below is the exhaust offered by Corsa taken off of their website. The similarities seem odd to me. The fourth & fifth picture is off of Borla's website, and the tips seem to be different than the tips on GM's site. I'm so confused. Is it really that hard to show pictures on your website GM????
GM's Website

Corsa's Website

Borla's Website
Secondly, I'm wondering if you have to remove the spare tire to mount this GM Performance Exhaust on the truck. I really don't want to keep my tire in the bed.
Lastly, what is cruising drone like in both V8 and V4 mode? I'm concerned more about the drone in V4 mode as my truck will have multi-displacement and I've heard bad things about V4 drone.

If you have any information or can post some pics of this system (dual or single outlet) that would be greatly appreciated. Thanks guys, this seems to be a very helpful and mature forum from what I've read so far. Cheers.

-Andrew

hotwheels57 · July 12, 2007

It's more than likely that the GM tips are slightly different than the BORLA tips to distinguish them as coming from GMPP. Lots of companies do that. GM wants you to buy your performance exhaust from them, not their vendor that produces it.

I've been researching both BORLA and CORSA for my '07 Silverado LTZ crew cab 6.0L. I plan to buy direct from one of them rather than buy from GMPP, paying that extra money for the product, plus more money for the installation to get a lifetime warranty through GM. Both BORLA and CORSA already have a lifetime warranty whether it's professionally installed or DIY.

I'm told that neither one require removal of the spare tire.

Both BORLA and CORSA told me that there is a slight difference in the exhaust tone when in V4 mode. Their sound cancelling technology reduces it significantly, but it's still there. I wonder if the sport exhaust makes it more noticeable than the touring exhaust? Maybe that's why my 6.0L oem exhaust has that secondary resonator just behind the rear axle.

5.3Avalanche · July 13, 2007

It's more than likely that the GM tips are slightly different than the BORLA tips to distinguish them as coming from GMPP. Lots of companies do that. GM wants you to buy your performance exhaust from them, not their vendor that produces it.
I've been researching both BORLA and CORSA for my '07 Silverado LTZ crew cab 6.0L. I plan to buy direct from one of them rather than buy from GMPP, paying that extra money for the product, plus more money for the installation to get a lifetime warranty through GM. Both BORLA and CORSA already have a lifetime warranty whether it's professionally installed or DIY.

I'm told that neither one require removal of the spare tire.

Both BORLA and CORSA told me that there is a slight difference in the exhaust tone when in V4 mode. Their sound cancelling technology reduces it significantly, but it's still there. I wonder if the sport exhaust makes it more noticeable than the touring exhaust? Maybe that's why my 6.0L oem exhaust has that secondary resonator just behind the rear axle.

In the Borla picture it shows the exhaust coming out at the sides on the rear end, but the GM picture shows the tips coming out the rear parallel with the sides of the truck. This is more than just different tips as the tubes have to be bent in order to angle the tips. Just another part of my confusion. Thanks for your response though.

dsmazz · July 13, 2007

GM Accessories sells a tire inflator that is for use with the GM dual exhaust system. Reason? The spare has to be deflated for the pipes to clear the spare. Dealer told me the spare had to be removed with the new GM catback, or deflated. I don't believe such is the case with the Corsa dual system. You can pick up the Corsa system for a lot less than the GM or Borla systems, and I think the Corsa system is better, but that's just my opinion.

MS3DALE · July 13, 2007

Mazz is correct,You have to remove the spare to install the GM system,With the CORSA you do not.

I also vote for the CORSA system,Its what I have on my '07 6-liter Vmax and also what I had on my last two trucks (All of them the "Sport" system)

And the tips are different,The system you would get from GM has either the Chevy bowtie or "GMC" embossed on them where the system you would buy from Borla does not.

And don't worry about about the noise in V4 mode with the CORSA system,Its not that noticable at all.

5.3Avalanche · July 13, 2007

Mazz is correct,You have to remove the spare to install the GM system,With the CORSA you do not.
I also vote for the CORSA system,Its what I have on my '07 6-liter Vmax and also what I had on my last two trucks (All of them the "Sport" system)

And the tips are different,The system you would get from GM has either the Chevy bowtie or "GMC" embossed on them where the system you would buy from Borla does not.

And don't worry about about the noise in V4 mode with the CORSA system,Its not that noticable at all.

Dale, where do the tips exit on the GM system. Do they come straight out the back or out to each side behind the rear wheels?

MS3DALE · July 13, 2007

Mazz is correct,You have to remove the spare to install the GM system,With the CORSA you do not.
I also vote for the CORSA system,Its what I have on my '07 6-liter Vmax and also what I had on my last two trucks (All of them the "Sport" system)

And the tips are different,The system you would get from GM has either the Chevy bowtie or "GMC" embossed on them where the system you would buy from Borla does not.

And don't worry about about the noise in V4 mode with the CORSA system,Its not that noticable at all.

Dale, where do the tips exit on the GM system. Do they come straight out the back or out to each side behind the rear wheels?

They come straight out the back.

5.3Avalanche · July 13, 2007

Mazz is correct,You have to remove the spare to install the GM system,With the CORSA you do not.
I also vote for the CORSA system,Its what I have on my '07 6-liter Vmax and also what I had on my last two trucks (All of them the "Sport" system)

And the tips are different,The system you would get from GM has either the Chevy bowtie or "GMC" embossed on them where the system you would buy from Borla does not.

And don't worry about about the noise in V4 mode with the CORSA system,Its not that noticable at all.

Dale, where do the tips exit on the GM system. Do they come straight out the back or out to each side behind the rear wheels?

They come straight out the back.

You wouldn't happen to have any pictures of the Corsa system on your truck would you??

MS3DALE · July 13, 2007

No,I haven't had a chance to take or post any pictures (My brother has to do it for me,I have no idea how nor do I even have a camera to do it!!)

I don't have the dual-rear exit system,I have single-side w/dual tips exit system (It exits out right behind the right-rear tire) Heres what I have.... CORSA

July 13, 2007

If you are making the change for strictly sound reasons I highly recommend yo go to your friendly neighborhood muffler shop and just have a Magnaflow installed. Cut out the old muffler, weld in the new, weld on some tips,,,,, $250-300 later you're on your way and VERY VERY happy with your new sound.

Way less than a catback.

BigHerky · July 13, 2007

I've got a video of the corsa exhaust that ive posted a few times on this forum and you can see how it looks coming out the back.

5.3Avalanche · July 14, 2007

I guess nobody has the Borla system on their Nbs here.

5.3Avalanche · July 17, 2007

I guess nobody has the Borla system on their Nbs here.

anyone?

5.3Avalanche · July 17, 2007

I've got a video of the corsa exhaust that ive posted a few times on this forum and you can see how it looks coming out the back.

very nice

dlstewart01 · July 17, 2007

I don't know about the ones for the 07, but I had the GM cat-back for an 05 ext cab. It was a single pipe out the side like stock. The pipe dia was 2.75 the same as stock. It was the touring model. It was fairly quite. It was made by Borla. I spoke with Borla about the difference in sport and tiuring and they said the only difference is length of the muffler.

The Corsa is 3" dia and has far better quility in my opinion. I am running Corsa now. I only had the GM on for a short time. It is in the garage if any one is interested. The only thing, the chrome tip says GMC.

Also the main reasion I am useing Corsa instead of the GM is the GM interfears with my helwig rear sway bar. The Corsa doesn't.

Thanks and have a great day,

Don