5.3L vs 6.2L V8

the wanderer · May 26, 2020

9 hours ago, Grumpy Bear said:

A = F/M. Newtons second law of motion. "A" or acceleration is that thing you feel in the seat of your pants. You feel it as lateral force in a curve or restraint during braking. That shove to the back of the seat matting the gas. Thing is for a give mass (M) of the vehicle the force (F) could come from any motor and "feel" the same for the same rate of acceleration (A).

Until you asking the larger motor for a greater rate of acceleration than the smaller motor can provide there is ZERO difference between them.

So here's the question. How often do you plan on accelerating that requires more than 355 hp or tow that requires more than 382 pounds feet torque? I have a V6 with 285 horsepower and used it all but a few times playing. Even interstate merges at any speed you care to name she's up to it.

Not bragging up the smaller motors. Saying they don't 'feel' different until you ask them different.

The problem is you're not accounting for torque that is coming out of both engines, at the same RPM. These engines will give you different power and torque at any RPM you pick, with the V8 giving you far more torque than the v6.

Put them on a dyno, you will see the numbers. You don't have to work them hard to feel that that the one engine is delivering far more power at the same RPM as the other.

N55_6MT · May 26, 2020

24 minutes ago, the wanderer said:

The problem is you're not accounting for torque that is coming out of both engines, at the same RPM. These engines will give you different power and torque at any RPM you pick, with the V8 giving you far more torque than the v6.

Put them on a dyno, you will see the numbers. You don't have to work them hard to feel that that the one engine is delivering far more power at the same RPM as the other.

At WOT...

Torque is a product of the force of combustion which depends on the fuel/air charge in the cylinder.

I don’t know about you, but I don’t spend a lot of time at full pedal on a normal day.

To me, the more perceptible thing is how high the engine will rev to obtain my desired acceleration, and there is way more to this than just peak torque at a given RPM. The only time I “felt” a difference between the 5.3 and the 6.2 is at WOT, which isn’t how I normally drive.

Sure more torque is great if you need it, passing with a fully loaded TT at 80MPH might be an example of when the 6.2 will definitely come out ahead but that might just be an argument for getting a diesel if you’re regularly needing that level of performance.

BigMick2023 · May 27, 2020

5.3 is no slouch and would be more than satisfactory for probably 90% of truck owners IMHO.......it works very well for me and gets great MPG numbers.

If you have the need for more power on a regular basis or just want braggin' rights, by all means pay the premium and go for it.

I don't have the need and see no reason to pay the big bump for something I would very seldom if ever use.

If I truly had the need on a regular basis, I'd be looking at a diesel for sure.

JMHO...

Greyhound6.2 · May 27, 2020

I went with the 6.2 with max tow pkg because I tow 2-3 times a month and wanted the little extra comfort of knowing it was a little overbuilt for my needs. Granted my trailer is not terribly heavy around 6Klbs loaded 20' enclosed trailer and I towed it just fine with my previous V8 grand cherokee, strong cross winds were sketchy hence the move to the truck.

Grumpy Bear · May 27, 2020

1 hour ago, the wanderer said:

The problem is you're not accounting for torque that is coming out of both engines, at the same RPM. These engines will give you different power and torque at any RPM you pick, with the V8 giving you far more torque than the v6.

Put them on a dyno, you will see the numbers. You don't have to work them hard to feel that that the one engine is delivering far more power at the same RPM as the other.

The problem is understanding the problem. Your saying the 6.2 will out accelerate the 5.3. Okay. I agree. You say it makes more torque at any given rpm. Okay I agree with that too. But that isn't what I was saying. I'm saying for the SAME rate of acceleration.

0 to 60 in 7.3 seconds is .375 G's of acceleration. All motors, even the V6 and in all trims will accelerate at this rate. That's a pretty brisk pace on the street. My 4.3 in this RCSB is a bit quicker than that and has no trouble with traction control off making some smoke. You have a need to drive like that every time you move? 0-60 even at 10 seconds is brisk. .27 G's.

https://www.zeroto60times.com/body-style/pickup-truck/

Doesn't matter day to day that the 6.2 is a second quicker over the 5.3 in nearly every measure unless you're drag racing.

55 to 70 in 5 seconds is .137 G's. They will all do that empty. (mph not kph)

When it matters is pulling 7500 lbs plus up a 7% grade. If you need it to pass empty your taking chances that shouldn't be taken. Didn't they teach in drivers Ed the brake is the emergency pedal not the gas. Remember? Bear Right and BRAKE?

EXSlider400 · May 27, 2020

Showing my age... I have owned a range of years of GMC trucks/SUVs (This list does not include cars or other brands I have owned)

- 1988 4.3

- 1990 5.7 (Then 383)

- 1995 5.7

- 2000 4.8

- 2005 4.2

- 2007 5.3

- 2014 5.3

- 2014 6.2

- 2016 6.2

- 2018 6.6 L5P

- 2019 6.2 (AT4)

- 2020 6.2 (Yukon)

I used to tow a trailer with air shocks, a v6, and 4l60. Was it fun...no, but it did the job. The v4 now make as much power as the old v8 and that is not even including the extra advantages of the extra gears in the trans. They are all good choices. We love the 6.2 with 10-speed and yes it is not needed but it is more fun and sounds great. Race vehicle....no. Yea you can add power to the 5.3...but you can also add it to the 6.2 for similar costs. These trucks require a lot of money to compete with a light car so don’t expect either to set the world on fire (only a few have modded to that extreme). My wife has a bi-turbo V8 AMG....you want speed...that will do it. Get what you want but get it for you not others. Enjoy what you get and don’t mind the haters.

Yondu · May 27, 2020

On 5/20/2020 at 9:14 PM, Jonofmac said:

Modern knock learn factors don't necessarily wait until knock is detected. Knock is not a clear cut ping always.

Knock sensors are microphones. They can measure the relative combustion volume. They will detect when you're close to knocking well before you get to the audible pinging noise.

I tune GM (and some import) vehicles. I've seen this repeatedly. Hell, even the GM Gen 3 PCMs don't need to see knock to realize they're on low octane. If they do see knock, they will adjust more quickly, but it doesn't require knock to realize it's close to the threshold.

I can datalog my gen 5 truck and see when it knocks and see the knock learn factor.

Sent from my SM-N960U using Tapatalk

Oh my god no. For one, it's not a microphone it's a piezocrystal.

They can't measure relative combustion volume.

They pick up vibration and turn it to electric current. This is then filtered to what is determined to be pre ignition / pre detonation. They are REactive to knock that's already occured.

Please don't ever tune anyone else's vehicles.

Yondu · May 27, 2020

On 5/24/2020 at 8:18 PM, TXGREEK said:

It’s a SuperChips tuned 2018 and I don’t have to give it to much gas to go, it’s a beast. So far, I’m still loving it, I live in the city and most of the time I don’t even pay attention to the mpg’s but it’s definitely an excellent motor/transmission combination. I’ll never switch back to a smaller motor. Btw, I switched from a 2016 DMax to the 18 6.2 and never looked back.

Sent from Above

I have a tuned 5.3 and I don't have to give it much gas to go, btw. That's the tune changing the throttle rate as well as timing to make it more responsive. A tuned 4.3 can easily be more responsive than a 6.2.

Flat foot it and the 6.2 has more getup, but with LT 33-34" tires a stock 6.2 truck would have it's hands full with a tuned 5.3 on stock 18" wheels.

Edited May 27, 2020 by Yondu

Grumpy Bear · May 27, 2020

32 minutes ago, EXSlider400 said:

Enjoy what you get and don’t mind the haters.

Physics isn't hate and it isn't ever an argument. It just is.

If power is all your after 1970 454 LS-7 465 hp 610 lbs/ft torque. Carbs on gas and a little tuning 500+ NA at the crank. Slow rolling steam rollers.

I drag raced for years. I don't hate power. I hate wasting it.

TXGREEK · May 27, 2020

All I can say is, LMAO!

Sent from Above

Jonofmac · May 27, 2020

Oh my god no. For one, it's not a microphone it's a piezocrystal. They can't measure relative combustion volume. They pick up vibration and turn it to electric current. This is then filtered to what is determined to be pre ignition / pre detonation. They are REactive to knock that's already occured.
Please don't ever tune anyone else's vehicles.

Oh my God. Yes. Excuse me for giving a simplified explanation for those that don't have degrees in electrical and computer engineering. First, it's called a piezoelectric crystal, not a piezocrystal.

Yes, it's not a literal microphone, but it behaves in a similar manner, which is (to simplify it) convert combustion noise into an electrical current which can be sampled by a MCU's ADC. That vibration they detect is always present, not just during knock. Combustion is noisy.

Have you personally tuned a knock ****** system? Because unless you have, you have nothing to stand on other than your (lack of) "knowledge". I know how these systems work and have worked with them with several large OEMs. Knock is not a binary thing, despite what you think. There is not only a pinging that the ECU detects. The piezoelectric crystal characteristics are tuned for a resonant frequency to make actual knock frequencies more sensitive than combustion noise (glorified band pass filter). Since knock is not a simple YES/NO, they actually can (and DO) estimate how close to knocking you are. The "noise" from knock, is a result of peak cylinder pressure happening too early, and creates a non smooth pressure waveform vs time (if you plot cylinder pressure through the cycle). This jagged edge of pressure creates the pinging you hear, however the knock sensors are sensitive enough to pick up smaller magnitudes of this and even the absence of knock (misfire detection, anyone?). They have several different thresholds uses to determine when knock has happened, which vary per RPM, and load, and even cylinder which are uses to determine the relative "volume" of the combustion. This is not up for debate, this is quite simply how the systems work. It is NOT just responding to knock which has already occured, if that were true, misfire detection would not work). I even attached some literature for you to show I'm not talking out of my ass. Yes, it is tuned to detect knock frequencies (that's the goal of a knock sensor), but they measure the knock level. Note that knock level is merely an amplitude of combustion noise for a given frequency, and this can range from none to full on audible pinging.

I don't care how you think these systems work, dude. Thank you for providing literally 0 explanation to how you think the systems work and proving you don't actually know. Go back to buying canned tunes. Please don't spread misinformation.

Sent from my SM-N960U using Tapatalk

SMW · May 27, 2020

I’ve owned (2) 5.3 Liters and (1) 6.2 Liter which I currently have. The only reason I am still with GM is because of the 6.2 Liter. If this engine was not available, I would be in a Hemi or 5.0 Ford.

the wanderer · May 27, 2020

12 hours ago, Grumpy Bear said:

The problem is understanding the problem. Your saying the 6.2 will out accelerate the 5.3. Okay. I agree. You say it makes more torque at any given rpm. Okay I agree with that too. But that isn't what I was saying. I'm saying for the SAME rate of acceleration.

0 to 60 in 7.3 seconds is .375 G's of acceleration. All motors, even the V6 and in all trims will accelerate at this rate. That's a pretty brisk pace on the street. My 4.3 in this RCSB is a bit quicker than that and has no trouble with traction control off making some smoke. You have a need to drive like that every time you move? 0-60 even at 10 seconds is brisk. .27 G's.

https://www.zeroto60times.com/body-style/pickup-truck/

Doesn't matter day to day that the 6.2 is a second quicker over the 5.3 in nearly every measure unless you're drag racing.

55 to 70 in 5 seconds is .137 G's. They will all do that empty. (mph not kph)

When it matters is pulling 7500 lbs plus up a 7% grade. If you need it to pass empty your taking chances that shouldn't be taken. Didn't they teach in drivers Ed the brake is the emergency pedal not the gas. Remember? Bear Right and BRAKE?

I'm comparing the 6.2 to the v6, not the 5.3. You don't have to be WOT to notice the difference.

Both a v6 and a 6.2 might be going down the same road at the same speed when a hill shows up; as you approach the hill, the 6.2 keeps chugging, the v6 runs out of power and downshifts.

Grandma might be holding up traffic and you want to pass her; you drop your foot a little (not even near WOT) in both trucks, the 6.2 shoots forward, the v6 does it more slowly.

This is the part of your comment (farther up the thread) which is very very incorrect:

Quote

Until you asking the larger motor for a greater rate of acceleration than the smaller motor can provide there is ZERO difference between them.

We don't drive in a math text book. When you actually get in the trucks and daily drive them, the 6.2 just feels twice as strong. You obviously don't care about it, and that's fine.

EXSlider400 · May 27, 2020

11 hours ago, Grumpy Bear said:

Physics isn't hate and it isn't ever an argument. It just is.

If power is all your after 1970 454 LS-7 465 hp 610 lbs/ft torque. Carbs on gas and a little tuning 500+ NA at the crank. Slow rolling steam rollers.

I drag raced for years. I don't hate power. I hate wasting it.

Understood and many of us just enjoy having a little extra when we want it. I’m not saying drive like a fool because like you said that’s where dragstrip comes in, but a little extra power every now and again isn’t gonna hurt anything. If that’s the case, many can just get the four-cylinder

Grumpy Bear · May 27, 2020

3 minutes ago, the wanderer said:

We don't drive in a math text book.

No we don't drive math books. But this world we live in is under the direction of the laws of the Universe those books only explain. Those law are not like the laws of men. They can not be violated. Your understanding or not agreeing makes zero difference to these laws. Fact is if they could be then your truck wouldn't operate at all. Fact is any device is a collection of universal laws being worked out with a precision a human can't even imagine. Obvious to me is you not only do not understand this, which is actually fine, but you have no wish to. That the case I have no reason to continue explaining. Good enough? Great! Then we're done here.

4 minutes ago, EXSlider400 said:

Understood and many of us just enjoy having a little extra when we want it. I’m not saying drive like a fool because like you said that’s where dragstrip comes in, but a little extra power every now and again isn’t gonna hurt anything. If that’s the case, many can just get the four-cylinder

Nothing here I disagree with. A little extra power hurts nothing. I like power. Raced for years. Thing is the OP's question was about what is BETTER. Better has nothing to do with absolutes. It's about perception and preference. If a person sees no advantage to a 'difference' then it isn't better to him. Thus in my very first post I asked directly what he meant by better. What he received was everyone else idea of BETTER.

My explanations thereafter were to show that for the mundane utility we put our vehicles through the MAJORITY of the time there is no DIFFERENCE and without DIFFERENCE there is no BETTER. Understand? (you don't have to agree)