octane

[The_bald_eagle_machine]

I remember in my 1987 Trans Am GTA if I ran 87 i would get Pinging/knock from the engine. Running 93 i had none. I know that is an apples to Oranges thing trying to compare that to a 2011 Camaro SS but...

My car is tuned for 93 octane so I will probably just keep bending over at the gas pump and taking it in the you know what... I tell myself its all about the smiles per gallon not the miles per gallon.

I remember when I had my 2002 Chevy avalanche with the 5.3 that had a 6 inch lift and 35's... That thing got 8 miles to the gallon and It was a turd lmao. Filling up the 31 gallon tank used to make me cringe pretty bad...

[1JEWLDSSRS]

Yep, all about the smiles, not the miles!!!

[lbls1]

All of my vehicles require premium gas. That is what I fuel them with; It hurts sometimes, especially with the prices being high. I have peace of mind putting in the proper octane, and the cars seem to run best with it.

[demonspeed]

Originally Posted by lbls1

All of my vehicles require premium gas. That is what I fuel them with; It hurts sometimes, especially with the prices being high. I have peace of mind putting in the proper octane, and the cars seem to run best with it.

How anyone buys a vehicle and complains about the fuel it requires has never made sense to me. All of mine also require better than 87 (93 in the Camaro, 93 in the Regal GS, 89 in the Durango R/T). Smiles per gallon

As an aside, it’s been probably a decade since I’ve seen a “FLS6B” reference. Brings back LS1tech memories!

[redcoats1976]

Originally Posted by demonspeed

In your case, it would be a waste (unless the 3.6 actually recommends premium for best performance - which I don’t think it does). Unlike the performance engines (L99/LS3/LSA/LS7), there’s nothing in the V6 tuning to take advantage of the additional octane.

so even if i was planning on high speeds,summer heat and humidity i should just use 87 and save money? the V6 does have an over 10:1 CR,but i drive moderately anyway.too much traffic and too many fools attached to cell phones here.

[demonspeed]

Originally Posted by redcoats1976

so even if i was planning on high speeds,summer heat and humidity i should just use 87 and save money? the V6 does have an over 10:1 CR,but i drive moderately anyway.too much traffic and too many fools attached to cell phones here.

If you’ve not tuned it then I’d just follow the owners manual. When I am giving hard time about using premium I’m referring to the guys where it literally says in the owners manual that anything less than premium may not offer best performance or fuel consumption.

[NOT A 45]

Originally Posted by redcoats1976

so even if i was planning on high speeds,summer heat and humidity i should just use 87 and save money? the V6 does have an over 10:1 CR,but i drive moderately anyway.too much traffic and too many fools attached to cell phones here.

Yea I don't get it, the V6 actually has 11.5 to 1 compression whereas the LS3 has 10.7 to 1. Chevrolet recommends 87 for the V6 and at least 91 for the LS3. May have something to do with the direct injection the V6 has IDK.

[gtstorey]

The Direct injection would be a big part of it, probably most, but cylinder design and turbulence within (and much more) can also affect the need for octane to prevent knock.

[hudson773]

Originally Posted by lbls1

All of my vehicles require premium gas. That is what I fuel them with; It hurts sometimes, especially with the prices being high. I have peace of mind putting in the proper octane, and the cars seem to run best with it.

piece of mind, did you read your owners manual. COMPLETELY safe to use regular. read before you speak

[NOT A 45]

Originally Posted by gtstorey

The Direct injection would be a big part of it, probably most, but cylinder design and turbulence within (and much more) can also affect the need for octane to prevent knock.

I think your on to something Story....if you remember way back in the 90's GM went to the LT1 that had optispark....It delivered cooled coolant to the cylinder heads first and allowed for higher compression and more timing. No doubt delivering fuel at the peak time for combustion reduces pre ignition.

[NOT A 45]

Originally Posted by hudson773

piece of mind, did you read your owners manual. COMPLETELY safe to use regular. read before you speak

It is and I do most often, and it's only because of our fuel management system you can do that. These engines are capable of detecting spark knock and making adjustments accordingly to prevent it. Results are reduced power because it's not operating as designed. Safe, yes but only because GM designed this to reduce warranty repairs! Any German vehicle does not do this! I would advise you to learn a little more about this before you speak!

[Silveradoss573]

Originally Posted by lbls1

All of my vehicles require premium gas. That is what I fuel them with; It hurts sometimes, especially with the prices being high. I have peace of mind putting in the proper octane, and the cars seem to run best with it.

My wife's Altima calls for a minimum of 91 so that's what it gets. I once tried running 87 and it absolutely wanted nothing to do with it. I run no lower than 91 on my Camaro. My truck with the LC9 small block and flex fuel capability, i have ran everything from 87 to 93 and E85 and everything in between. The sweet spot on gas seems to to between 89 to 91 octane. When I run pump E85 (which is most likely E55 +/-), I can definitely feel a increase in torque no question.

[Royal Tiger]

Originally Posted by NOT A 45

It is and I do most often, and it's only because of our fuel management system you can do that. These engines are capable of detecting spark knock and making adjustments accordingly to prevent it. Results are reduced power because it's not operating as designed. Safe, yes but only because GM designed this to reduce warranty repairs! Any German vehicle does not do this! I would advise you to learn a little more about this before you speak!

Absolutely.

Really don’t understand how he’s been proven wrong a dozen times and he keeps doubling down on his nonsense.

[NOT A 45]

Originally Posted by Royal Tiger

Absolutely.

Really don’t understand how he’s been proven wrong a dozen times and he keeps doubling down on his nonsense.

I was always taught to speak less and listen more. I don't know everything that's why I joined this forum. On this topic I do know what I'm talking about....I have spent countless hours at GM's expense to learn how our systems work. When you guys talk of turbo's and superchargers and other modifications you won't hear a peep from me....I don't know that stuff but I want to learn. Yet I see over and over guys here giving bad advice to people. If you don't know what your talking about stay away from your keyboard!