6.2L gas 91 vs 93

[Snakes709]

24 minutes ago, Tr3kker said:

Because there is a difference. Maybe not seat-of-the-pants dyno testing, but with higher compression engines like the 6.2L (11.5:1). Arguably, the 6.2L is on the lower end of "high" compression, so there's not as much difference between running 87 and 91 fuel. Might as well save even more $$ and opt for the 5.3L if you don't need all those extra horsepower. 

 

https://www.youtube.com/watch?v=gqvhaPLuTPI

 

Currently -41*C (with the windchill) with snow and ice on the road. No need to go over 2000rpms or the extra hp.  So why spend $27 per tank extra?  I got no problem using 91/94 in the summer, but absolutely no reason to use it in the winter. 

[Tr3kker]

5 minutes ago, Snakes709 said:

Currently -41*C (with the windchill) with snow and ice on the road. No need to go over 2000rpms or the extra hp.  So why spend $27 per tank extra?  I got no problem using 91/94 in the summer, but absolutely no reason to use it in the winter. 

 

Wow! $27 CAD extra?  If I was getting gang-raped like that at the gas pump, I would probably run the lower octane (or buy a deisel). Down here in the lower 48 where there's only pennies (maybe a buck or 2) difference on a fill up, makes sense to run the higher octane.

[Snakes709]

12 minutes ago, Tr3kker said:

 

Wow! $27 CAD extra?  If I was getting gang-raped like that at the gas pump, I would probably run the lower octane (or buy a deisel). Down here in the lower 48 where there's only pennies (maybe a buck or 2) difference on a fill up, makes sense to run the higher octane.

Yea, 94.9/L for 87 and 125.9 for 94. If it was something like $5-10 difference per tank, the. Yea i would put premium in all the time.  But $27 per tank which i cant really use as the roads are covered in ice and snow is just pointless. 

[T1Kaiju]

 
Wow! $27 CAD extra? [emoji857] If I was getting gang-raped like that at the gas pump, I would probably run the lower octane (or buy a deisel). Down here in the lower 48 where there's only pennies (maybe a buck or 2) difference on a fill up, makes sense to run the higher octane.

Around here its never less than 40 cents more for 93, and usually its more like 80 cents. $10-20 a tank extra in DFW...

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[Cpl_Punishment]

3 hours ago, Tr3kker said:

 

Wow! $27 CAD extra?  If I was getting gang-raped like that at the gas pump, I would probably run the lower octane (or buy a deisel). Down here in the lower 48 where there's only pennies (maybe a buck or 2) difference on a fill up, makes sense to run the higher octane.

Yeah, premium is about a dollar a gallon (25 cents a litre) more here and we probably have the cheapest gas in the country. Diesel is about on par with premium, though; the days of cheap diesel seem to be over. 

[spizike9]

7 hours ago, Snakes709 said:

Yea, 94.9/L for 87 and 125.9 for 94. If it was something like $5-10 difference per tank, the. Yea i would put premium in all the time.  But $27 per tank which i cant really use as the roads are covered in ice and snow is just pointless. 

I get my gas at Costco usually and there is is usually about .20 difference between 87 and 91. I typically put in 20-23 gallons so it’s about $4.50-5.00 difference per fill up. I will usually fill up twice per month but occasionally 3 times. It’s only going to cost me an $10-15 a month to have the 6.2. 
 

I currently have a ‘18 SLT 5.3. Hoping to get a AT4 in 6.2 sometime this year. Kinda waiting for the rear window thing to fix itself and see if they end up doing the new interiors for the model year 2021. 

[Snakes709]

29 minutes ago, spizike9 said:

I get my gas at Costco usually and there is is usually about .20 difference between 87 and 91. I typically put in 20-23 gallons so it’s about $4.50-5.00 difference per fill up. I will usually fill up twice per month but occasionally 3 times. It’s only going to cost me an $10-15 a month to have the 6.2. 
 

I currently have a ‘18 SLT 5.3. Hoping to get a AT4 in 6.2 sometime this year. Kinda waiting for the rear window thing to fix itself and see if they end up doing the new interiors for the model year 2021. 

Havent had any issues with my rear window with the AT4.  Only issues i have had is “service 4wd” any time i switched to any of the 4wd’s. Had it happen 3 times, each time the dealership does a system relearn and sends me on my way.  Hasnt done it in quite awhile though so i think the 3rd time it fixed it. 

[AlaskaErik]

On 1/11/2020 at 6:38 PM, Colossus said:

Stick with top tier fuels and run some good cleaner in there a few times a year, like BG44k or Techron concentrate. 

The whole idea with using top tier gas is so you don't have use additives.  My Hyundai even stated in the owner's manual that if you don't use top tier gas you need to use an injection cleaner, such as Techron, every so often

[PabloK]

I run non-eth 93... don’t care about the cost.

If your getting the big engine why leave performance on the table?

Honestly... if you want more performance, throw the shifter all the way down then manually gearing up to D9. its fukin epic.

The cylinder deactivation ruins the V8.... this drops it... it’s night and day difference.

More power, all the time, no hesitation, sounds better, shifts better

Swapping my ecu soon so I don’t have to manually do it every time.



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[PabloK]

Currently -41*C (with the windchill) with snow and ice on the road. No need to go over 2000rpms or the extra hp.  So why spend $27 per tank extra?  I got no problem using 91/94 in the summer, but absolutely no reason to use it in the winter. 

 

Your already running the engine in extreme conditions... now your just adding more stress to your truck.

 

First, With high octane fuel, engine designers are able to implement various techniques to improve reliability, efficiency, and power output. First, it helps prevent knock. Engine knock, or pinging, occurs when a separate pocket of air-fuel mixture ignites after the spark has ignited the air-fuel mixture within the combustion chamber. This is obviously undesirable as it can cause serious engine damage, and it can be prevented by using the proper octane rated fuel.

 

Second, higher octane allows for the use of higher compression ratios. Compression ratio is directly linked with thermal efficiency, so the higher the compression ratio, the more efficient the engine will be (law of diminishing returns certainly applies).

 

Third, high octane fuels allow for advanced ignition timing. What this means is the spark is fired well before the piston reaches top dead centre on the compression stroke. The reason this is done is because it takes time for the flame front to expand out and combust the air fuel mixture. If you start this process in advance of the piston reaching top dead center, you can increase the maximum pressure the cylinder will have once the air-fuel mixture is fully compressed (and traveling downward), and this will result in increased power. Obviously you do not want to detonate too early, as you’ll be applying pressure in the wrong direction, but if you ignite too late, you’re losing valuable torque.

 

 

 

 

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[Snakes709]

10 hours ago, PabloK said:

 

Your already running the engine in extreme conditions... now your just adding more stress to your truck.

 

First, With high octane fuel, engine designers are able to implement various techniques to improve reliability, efficiency, and power output. First, it helps prevent knock. Engine knock, or pinging, occurs when a separate pocket of air-fuel mixture ignites after the spark has ignited the air-fuel mixture within the combustion chamber. This is obviously undesirable as it can cause serious engine damage, and it can be prevented by using the proper octane rated fuel.

 

Second, higher octane allows for the use of higher compression ratios. Compression ratio is directly linked with thermal efficiency, so the higher the compression ratio, the more efficient the engine will be (law of diminishing returns certainly applies).

 

Third, high octane fuels allow for advanced ignition timing. What this means is the spark is fired well before the piston reaches top dead centre on the compression stroke. The reason this is done is because it takes time for the flame front to expand out and combust the air fuel mixture. If you start this process in advance of the piston reaching top dead center, you can increase the maximum pressure the cylinder will have once the air-fuel mixture is fully compressed (and traveling downward), and this will result in increased power. Obviously you do not want to detonate too early, as you’ll be applying pressure in the wrong direction, but if you ignite too late, you’re losing valuable torque.

 

 

 

 

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I know how engines work and what higher octane does. Putting 87 in my truck wont cause any damage and putting 94 wont help it any either.  You want to explain how im adding more stress to it when i dont go above 2000rpms or past 1/4 throttle? And no signs of knock or pinging?

[diyer2]

Where do people get their ideas from?

[Ezekiel2517]

I run 89 unless I am towing.  Then Ill go with 93.  Im just piddling around town so I dont need high performance to cruise to wrk and haul kids.  It runs fine and gets the same MPG.

[Colossus]

On 1/12/2020 at 7:53 PM, AlaskaErik said:

The whole idea with using top tier gas is so you don't have use additives.  My Hyundai even stated in the owner's manual that if you don't use top tier gas you need to use an injection cleaner, such as Techron, every so often

What auto repair experts are finding is that even top tier fuels are not getting a lot of the carbon build up with the direct injection engines which is why running a heavy duty cleaner like the Techron concentrate or BG44K a few times a year has it's advantages. 

 

Here is one of the few articles I have read that does a good job of explaining what I mean:

 

https://www.underhoodservice.com/carbon-deposits-direct-injection-engines/

 

[SSoto]

I just recently picked up a 6.2L AT4 Carbon Pro. I drive an average of about 30k miles per year. My company provides FREE 87 octane gas (up to 40 gal/week). So far I've filled up 3 times (twice with 91 and once with company gas). I haven't noticed a difference so far but i'm still getting accustomed to the truck. What would those in the, "Premium ONLY" camp do in my situation? I'm thinking about running 8oz of Boostane PRO with every 20 gal fill-up which would take the octane to 92/93. If i did that with every fill it would cost me about $7.50 a pop ($30 for 32oz). Thoughts?