Performance Upgrade Package

bigdog2005 · March 8, 2020

On 2/21/2020 at 10:41 AM, MG386 said:

With a little spray of silicone lube on each one, and a pair of channel lock pliers, it's pretty easy to remove hangers. You could probably do it without the pliers.

The ECM program flash is included with the GM intake. I drove around for a few days with both intake and exhaust without the re-program and had no issues.

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Well I keep hearing about reflashing the ECM when using the GM CAI. Is it really necessary and did you notice a difference after reflash?

Reason I'm asking, I bought a 2020 RST with the 6.2 a couple weeks ago and installed the Borla S-Type system and Cold Air Inductions CAI. No issues with codes or anything but I keep hearing that without the flash I'm not getting the full experience.

MG386 · March 9, 2020

Honestly I couldn't tell a difference with or without the flash. No codes or problems either way. Just my OCD that makes me feel better knowing that it's done and everything working as designed. And it's free, so.... Why not.

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[email protected] · March 9, 2020

Can someone tell me the part number for the GM performance exhaust for a 2020 AT4 6.2?

MG386 · March 10, 2020

Can someone tell me the part number for the GM performance exhaust for a 2020 AT4 6.2?

84527234

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Josh Tittle · March 11, 2020

On 2/24/2020 at 5:01 PM, Supercup said:

My 2019 AT4 Carbon Pro came with cat back, but not the air box. So I picked up an OEM cold air box and asked dealer to do tune also when they installed - they looked at me like they had no idea what I was talking about. I showed them some write ups from GM where it states tune is part of performance package. They said they would look into it.

When I picked truck up they said the tune instructions were in the instructions for the air box install, so the tune was added - so I now have the performance package complete! So if you add OEM airbox, you will get that updated tune!

Hi, I currently have the OEM Cat back exhaust and really like it. I am thinking about pairing it with the OEM cold air intake.

1. Did you notice much of a sound difference adding the CAI? If so, is it a lot?

2. If you had it to do over again, would you have purchased the CAI or did you prefer just the exhaust upgrade?

Thanks!

zeon · March 12, 2020

On 3/18/2019 at 7:25 PM, Jon D said:

I did both and am happy with the outcome. Much better sound and the truck just feels a bit more lively.

Would you do it again and did you see any improvement in fuel mileage mine has the exhust but didn't come wither cai just trying too justify the money. They say it makes a lot more noise too. Thx

Jtelder · April 2, 2020

So, All in all is the performance package worth it? Do you love it?

TRKLGND · April 2, 2020

On 3/8/2020 at 8:23 PM, MG386 said:

Honestly I couldn't tell a difference with or without the flash. No codes or problems either way. Just my OCD that makes me feel better knowing that it's done and everything working as designed. And it's free, so.... Why not.

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I wouldn't think you could notice 15hp. Looks good on paper though. If I paid for the performance package I would definitely want to know that the new calibration was in place.

davidr83 · April 2, 2020

On 3/6/2020 at 8:32 AM, Sfcdjf said:

Still in shop. It was a dealer trade and they believe the dealer did not flash the ecm corectly. They can not get the ecm to do anything now. So thier going to change the ecm, do a new install on it and see if that will fix the problem. By the way, if you didnt know, anything plugged into the obd port is now permanently logged into the Ecm memory. The reprogram itself can be returned to stock, but a log is stored showing the techs time and date of ecm changes that were not done by a gm tech computer. This was gm's answer for the diesel owners deleting def systems. Now thier using it on gas trucks too. Tech says it automatically voids warranties now. Learned all this from master tech who was awsome enough to let me see thier equipment

When I had the CEL on my 3.0 Duramax, I used my hptuners to pull the code and clear it twice before taking it in to the dealer and they didn't say anything to me about this. They Just updated the software and gave me a print out of what they did and sent me on my way. No check engine light since then too.

Supercup · April 8, 2020

On 3/11/2020 at 9:37 AM, Josh Tittle said:

Hi, I currently have the OEM Cat back exhaust and really like it. I am thinking about pairing it with the OEM cold air intake.

1. Did you notice much of a sound difference adding the CAI? If so, is it a lot?

2. If you had it to do over again, would you have purchased the CAI or did you prefer just the exhaust upgrade?

Thanks!

Sorry for late reply - haven't been on lately - I would do it again - 15 hp from the combined package - 3 hp from the OEM CIA - so not much of a power gain - change in noise is minimal - but you get better flow and it looks a lot better when you open the hood. I would do it again - not really needed (performance package) - but why not, every little bit helps and OEM mean no warranty issues.

zeon · April 16, 2020

When I bought my AT4 it had the performance exhust seemed like it couldn't breath or something wrong I had Magaflow on my 2019 it did great so I went to the dealership and drove one with the cai and performance exhust couldn't believe the difference it made . At 4000 I Had it put on mine and it's breathes and runs and idles so much better. I had them do it all they reprogrammed it set everything up to specs loving it now let you know later if it help anything else

Edited April 16, 2020 by zeon
mis spell

INTJ · April 18, 2020

On 3/2/2020 at 9:06 PM, Duramax.willard said:

I have a 2019 Denali with a 6.2l, had a custom made exhaust from Heartthrob Exhaust designed and built (now available as a kit from their website, you're welcome). Dyno sheets showed a 52rwhp gain. Noticeably different while driving and not obnoxiously loud at all. Yellow is before, green after.

See video of sound here.

I am puzzled why this hasn't been broadcast everywhere. 50 HP for a cat back, meaning emissions and warranty aren't affected. They only show one for a short bed but I'll bet they'd make one for a standard bed.....

Edited April 20, 2020 by INTJ

Cameron601 · April 20, 2020

On 2/26/2020 at 8:35 PM, Glava2876 said:

I just bought my GMC with the 6.2 10A actually picking it up Friday.

I wanted performance brakes, exhaust and intake, but I bought it off of the lot and it only had the brakes.

When I asked the sales person about it he said he didn't think that the exhausts sounded much different from stock -which, based on this thread, I see isn't the case.

I had thought that I'd just order the parts and install them myself --can you just download the tune when you get the CAI or do you have to bring it to the dealer?

how do you like the performance brakes? I assume it is the Brembo ones right?

Glava2876 · April 21, 2020

On 4/20/2020 at 9:47 AM, Cameron601 said:

how do you like the performance brakes? I assume it is the Brembo ones right?

Well, they definitely feel stronger than my 2015 Denali, but I actually only have about 650miles on it so far with working from home.

Yes they are the Brembo brakes, and actually look the same as the ones on my Z06. The only odd part is that the brake life monitor is maintained on the rear brakes, but not on the front.

Musgo · April 29, 2020

Any one have any decibel readings inside the cab at highway speeds? I went thru a headache with my 2014 and a borla s type being too loud. How's the loudness with towing?