Beware of Cold Air Intakes

[red44]

On 2/22/2025 at 7:56 AM, KARNUT said:

I used to modify my trucks. There’s nothing I would do to my truck that wasn’t blessed by the dealer. Even changing the tire size. They’re so jammed up with sensors and technology it’s easy to mess them up. If you happened to get a problem truck or a recall you’re screwed. You can order or buy a truck with just about anything you desire. Spend the money on extended warranty. Leaving the mods to the manufacturer. 

I agree, mostly, but I used to have a 2011 Silverado with crap suspension. The first time I ran into trouble it was all still under warranty, so no issues there, but it happened again a couple of years later and I went aftermarket because it was way cheaper and all the problems mysteriously disappeared.

Probably different these days with newer trucks though. 

[KARNUT]

1 hour ago, red44 said:

I agree, mostly, but I used to have a 2011 Silverado with crap suspension. The first time I ran into trouble it was all still under warranty, so no issues there, but it happened again a couple of years later and I went aftermarket because it was way cheaper and all the problems mysteriously disappeared.

Probably different these days with newer trucks though. 

2011 is still ok. I put exhaust and a tune on a 2014 my last new one. 

[Red6.2]

I did end up getting the performance intake part number from a 2025 Silverado since they are able to be optioned from the factory. My question is am I able to somehow get the calibration from the dealer or does the truck even need that?

[Bikerjon]

On 2/26/2025 at 10:15 PM, Red6.2 said:

I did end up getting the performance intake part number from a 2025 Silverado since they are able to be optioned from the factory. My question is am I able to somehow get the calibration from the dealer or does the truck even need that?

What is the part # for the 6.2L CAI? Usually when you buy a part from GM the calibration comes with the part. You pay for the calibration when you purchase the part and you get verification code for the dealer to program your truck.

[Red6.2]

1 hour ago, Bikerjon said:

What is the part # for the 6.2L CAI? Usually when you buy a part from GM the calibration comes with the part. You pay for the calibration when you purchase the part and you get verification code for the dealer to program your truck.

It was 87845963

[Transient]

On 2/25/2025 at 9:01 AM, Dan H 2023 HC said:

"up to a +13 hp improvement at 5600 rpm and up to 8 additional pound feet of torque at 4100 rpm"

 

Key words "up to", and notice the RPM's where those potential max gains occur. What do the gains look like at between 1500 and 3500 where these engines spend most of their time?

 

CAI's and CAT back exhaust systems just aren't going to make a noticeable difference at lower engine speeds. The stock AI and dual exhaust systems are more than capable of flowing enough CFM probably up to 4-4.5K RPM, and the stock air intake is already pulling air from in front of the radiator, not from the engine compartment. If those aftermarket bits do add anything at lower RPM I'm hard pressed to believe one could actually feel it. You could have a 3 or 4 HP/TQ variation from day to day just due to atmospheric/barometric pressure changes.

 

 

First off, there's nothing aftermarket about those claims.  That's from GM.  I even provided the links.  Secondly, wanting hp numbers from 1500 to 3500 rpms is ridiculous regardless of the application we're talking about.  The horsepower curve doesn't intersect the torque curve until 5,252 rpms.  3rd I never said it was felt.  I only quoted and cited the claims. 

[Transient]

On 2/27/2025 at 10:38 PM, Bikerjon said:

What is the part # for the 6.2L CAI? Usually when you buy a part from GM the calibration comes with the part. You pay for the calibration when you purchase the part and you get verification code for the dealer to program your truck.

That is exactly how it worked for me when I installed it.  I jumped in my truck and headed straight to the dealer so they could do the tune.  All I had to do was provide the paperwork so could book it to GM correctly. 

[66ss3964spd]

Doesn't matter if the claim is from an aftermarket supplier or from GM, it is still a claim, and likely made under the most favorable conditions, which is why the words "up to" are used.

 

While the HP/TQ cross over point is irrelevant, I would argue that the torque curve is not, especially in a heavy vehicle. The more torque that is available at lower RPM the faster the vehicle will accelerate. Approximately no one is driving these things around daily with the tach pinned at peak torque RPM (4100 for the 6.2 and 5.3), so the torque numbers in the RPM range that these engines spend most of their time in do matter.

 

If someone is contemplating spending money on a performance upgrade, information is powerful. Being able to see the actual curves first helps them to make an informed decision based on their needs and driving style. Though the claim is up to 13 lb-ft at 4100, if it is only adding 5 or 6 lb-ft in the usual RPM range then, to me, the juice isn't worth the squeeze, but it certainly may be to someone else. Of course that's just my opinion.

[Transient]

On 3/2/2025 at 9:28 AM, Dan H 2023 HC said:

Doesn't matter if the claim is from an aftermarket supplier or from GM, it is still a claim, and likely made under the most favorable conditions, which is why the words "up to" are used.

 

While the HP/TQ cross over point is irrelevant, I would argue that the torque curve is not, especially in a heavy vehicle. The more torque that is available at lower RPM the faster the vehicle will accelerate. Approximately no one is driving these things around daily with the tach pinned at peak torque RPM (4100 for the 6.2 and 5.3), so the torque numbers in the RPM range that these engines spend most of their time in do matter.

 

If someone is contemplating spending money on a performance upgrade, information is powerful. Being able to see the actual curves first helps them to make an informed decision based on their needs and driving style. Though the claim is up to 13 lb-ft at 4100, if it is only adding 5 or 6 lb-ft in the usual RPM range then, to me, the juice isn't worth the squeeze, but it certainly may be to someone else. Of course that's just my opinion.

GM utilizes the same SAE certification testing requirements on all its claims, with and without their GMP intakes.  We should also acknowledge that slight manufacturing variations in all the parts in the engine also affect how much power they make regardless of the intake.  That's why GM says (for example) SAE rated up to 420bhp/460btq on the 6.2 engines without the GMP intake.  However, GM has been known to underrate the actual output of its powertrains.  They do their own SAE testing in house, and there's very little oversight on the self-reporting standards in the industry.  The actual output for a specific engine may be higher than rated.  Only way to know is to pull the engine from the vehicle and dyno it.  Nobody is going to do that with a brand new vehicle, unless they're Gail Banks. 

 

Your opinion is yours, and you're more than welcome to it.  Just realize that I didn't share my opinion for the same reason yours is unwarranted -- nobody cares because opinions are like buttholes.  Everybody has one, and they stink.

[66ss3964spd]

On 3/2/2025 at 2:37 AM, Transient said:

Secondly, wanting hp numbers from 1500 to 3500 rpms is ridiculous regardless of the application we're talking about.

Is that not your opinion?

 

Regardless, your opinion about offering unrequested opinions is noted and appreciated. 

[KARNUT]

A persons contentment and happiness is all that matters. I modified everything only to go 70 mph hour after hour. Mostly bench racing. An extreme example is my brother in law. He drives a one ton diesel everyday. Only to pull his fancy fishing boat about 6 times a year or his fifth wheel camper during hunting season. His 401K is current. And he is happy and puts up with his demanding job because of his toys. I had collector cars he had his boat. Work hard, live large and save for the future. Chances are when you retire you’ll be lucky if you can change your hobby. Drag racing or hunting and fishing will be a regret that you didn’t do. Because you waited for retirement. You’ll be struggling dragging your but to play bridge. Your new exiting retirement hobby. So if duals and cold air intake is only good for higher RPMs. The highway entry ramps are a little more fun. That’s all that matters because it puts a smile on your face.

[66ss3964spd]

19 minutes ago, KARNUT said:

That’s all that matters because it puts a smile on your face.

No argument there at all. Smiles per miles matter.

 

I recently installed quad exhaust tips on the truck and sent my youngest photos of them.

Him: Do they make it sound better?

Me: No.

Him: Do they improve performance?

Me: No.

Him: Then, why?

Me: Cuz I like them.

 

I've been a car guy since my early teens and have had a collector car for over 25 years. Constantly making "improvements" to it which my spouse doesn't understand. But I do. 

[Silverado4x4]

4 minutes ago, Dan H 2023 HC said:

No argument there at all. Smiles per miles matter.

 

I recently installed quad exhaust tips on the truck and sent my youngest photos of them.

Him: Do they make it sound better?

Me: No.

Him: Do they improve performance?

Me: No.

Him: Then, why?

Me: Cuz I like them.

 

I've been a car guy since my early teens and have had a collector car for over 25 years. Constantly making "improvements" to it which my spouse doesn't understand. But I do. 

I agree, back in the day running 4bbl carbs I always flipped the air cleaner lid over just to hear that 4bbl sing. Did it improve HP no probably hurt but I didn't care cause I liked the sound.

[KARNUT]

2 hours ago, Dan H 2023 HC said:

No argument there at all. Smiles per miles matter.

 

I recently installed quad exhaust tips on the truck and sent my youngest photos of them.

Him: Do they make it sound better?

Me: No.

Him: Do they improve performance?

Me: No.

Him: Then, why?

Me: Cuz I like them.

 

I've been a car guy since my early teens and have had a collector car for over 25 years. Constantly making "improvements" to it which my spouse doesn't understand. But I do. 

I hear you. My wife recognizes my addiction early. I got an allowance and started flipping cars in the seventies. If it had a letter like SS or GT. Or a number like 442 I had at least one. 

[66ss3964spd]

3 hours ago, Silverado4x4 said:

I always flipped the air cleaner lid over just to hear that 4bbl sing.

Yeah, the old air cleaner lid flip. Really made Quadrajets sound great when those giant secondaries started opening up.

 

1 hour ago, KARNUT said:

My wife recognizes my addiction early.

Mine did too. Still doesn't understand it, cars aren't much more than an appliance to her, but she still lets me indulge.