Does Everyone Use Regular?

What kind of mileage are some of you getting? Are you getting a difference in mileage by switching to premium?

 

It makes no difference. Really it doesn't. If you think it does it is all in your head. If you believe it does you are imagining it

 

I got zero increase in mileage. Drivability with my m/t was improved, however.

 

knock sensor, almost forgot about that, good point

 

You can advance timing all you want. You're not going to stretch your piston rods or lower the cylinder heads to make more compression. Which is where octane is relevant.
Same goes for cam timing. Unless you installed those variable displacement camshafts...?
And as another person has said, how would it know? Point to the octane measurement unit under your hood.

 

The ethanol mandate came from the Bush era, and is supposed be in favor of energy independence. Believe me though, ethanol is much worse for the environment than just using straight gasoline, and any true environmental advocate is not in favor of it. Farmers like the subsidies though.

 

You can still get predetonation, or knock, in lower compression engines. Higher octane helps prevent it, that's the point. Not saying you'll get more power out of it, but if your ECU is pulling timing regularly, it would be a good idea to use a higher octane. One of reasons I monitor timing advance on my Ultragauge. Mine seems to do great on 87, but I have heard folks on here with the V6 who say they get knocking that clears up when they use higher octane.

 

If they're running an older truck, then sure. Carbon deposits can cause pre-det, or knock, and a higher octane can help due to slower flame propagation. But on a new engine? It makes my skepticism say their ass-dyno needs calibrated.

 

Cams have a lot to do with dynamic compression ratio so I don't understand your statement there.

If you put too low octane in an engine with a know sensor, it will pull the timing, so why would it do that if octane has nothing to do with timing?

 

You're still operating under the assumption that while all our trucks call for 87, there's like a magical back door ECU program that'll make it produce more power. It's baloney and you know it.

Sure. In this fictitious 3.5L capable of measuring octane numbers and infinitely adjusting timing and valve sequence you could in theory use and benefit from a higher octane. You're talking about the kinds of things used in higher performance engines to then retrograde performance to deal with crap gas. But you're trying to apply it forward on an engine which,by its own manufacturer, is rated for 87. Just stop. Seriously. I can pee farther and with more volume. Just accept it.

 

No, I'm saying it is POSSIBLE, you are saying you know it for a FACT. And your wrong, you don't know for sure. As a matter of fact does the 3.5 not have a simulated Atkinson cycle that works by cam timing that lowers the dynamic compression? So I really don't see it too much as a stretch that this engine COULD run better or worse with different fuels.

 

You're assuming it has a baseline above what the manufacturer created as it's baseline. You're fantasizing. Lots of things are "possible" in the realm of fantasy. Any engine can run worse on crap fuel. But you have to have the base mechanical ability to run better on better fuels. We can go from baseline and decrease it only. To increase it would take differently shaped and manufactured hard parts.
"The Atkinson cycle can manipulate effective cylinder volume."
Ya got me.
It can manipulate it LOWER nimrod. It can't make it higher because as I pointed out, rod length isn't variable, and therefore cannot Increase compression ratio and therefore cannot truly exploit benefits from a higher octane rating. I KNOW this. It's doggone physics and science. Read a book. Smh. Goodnight psc199333. I'm sure you have school in he morning if you're not already too tired from the schooling tonight.

 

You haven't schooled anyone, all you've done is personal attacks and be insulting the entire thread. Look all I'm saying is that it is POSSIBLE for me, and other people here,to have increased drivability and acceleration with higher octane fuel. I don't really see where calling someone a nimrod really supports your arguments, but whatever, I've been called worse.

 

You guys running 87 ethanol blend; are you sure about the octane?
If the actual E number of the gas is lower than what's advertised on the pump, you get less than the advertised octane.
If 87/E10 separates, the top layer becomes 84 octane.

FWIW, I use 91 non-ethanol

 

76 station on Imperial hwy off the 57 fwy. has 93.

 

Shell 87.

Folks got to take a physics class or do some reading before entering the world of Octane. You can do a lot of things with higher Octane ratings but believing you get better gas mileage due to the higher octane rating defies logic...not to mention science.

Take Care

Bob

 

No difference than cost more for premium. I get awesome fuel mileage when I keep my foot out of it and drive 60 mph or less.