Octane difference?

I've checked a number of stations here in southern AZ. They all have the same vague sticker on them: May contain up to 10% ethanol.

Have yet to find non corn gasoline here.

 

Since I ain’t no scientist, so I will stick to what the US EIA says about gas btu and what octane means. Unless you have scientific evidence that says other wise. Sorry but I can’t take 1 person’s evidence based on what a Master tech told him.

 

If it's that easy to gain 50hp and 2-3 mpg Toyota don't need all those R&D money to make the new Iforce max...just slap a premium fuel only sticker inside the gas tank door and call it good...lol

 

ya, but not 50hp and/or 2-3 mpg difference on a NA engine and all engine have a max timing, so basically you just moving the power curve to lower RPM.

 

If is that easy, dealer just need to have their own gas station and make customer go their to fill up right

 

Don’t know all the science. But with my 91 Toyota pickup I get 3 mpg better with ethanol free premium over regular crap. 2010 Tacoma got 2-2.5 mpg better. My tundra gets premium ethanol free with every fill up and always will. I like the extra range and need it during hunting season.

 

If I knew premium here was corn free, I'd use it.

 

Here's what I learnt.

vs. Gas
Ethanol has higher octane. ~110
Ethanol has lower BTU.

and ...you can pick your octane, but you can't pick your BTU.

Gas is gas.
since adding corn to gas will lower it's btu's - Gas with corn is not as good as non-corn gas.

facts below.

 

oh...and batteries suck.

 

Cute picture. Show me the scientific evidence that 87 octane has less btu than 93 octane. Show me numbers since you believe in numbers. I posted my evidence and that’s what I go by. I am not going to just change my mind because some guy on the internet posted a pic and said so. I am sure that the thousands to hundreds of thousands high mileage vehicles still running out there didn’t all run 93. I am also sure that they have more money in their pockets, since 87 is cheaper. I am also sure that there is no scientific evidence that 93 will make an engine last longer. Just there is no evidence that expensive oil will make an engine last longer. If so the million mile tundras beg to differ. And if 93 is so great, why not just make 93? I mean, I am sure 93 will burn perfect in a 7-1 or 8-1 compression engine.

If your not going to show me an experiment done on different fuels, stop replying with long and small hydrocarbon chains.

 

Engine Masters has a good show about octane differences

Does the Fuel You Choose Matter? | Engine Masters | MotorTrend - YouTube

I typically run higher octane in summer months and lower octane in cooler months.

Octane rating (Research octane + motor octane)/2 is a measure of volatility under pressure. BTU is a measure of thermal energy released from combustion, assuming perfect combustion (and whether or not you are taking in account the heat of water vaporization...aka LHV or HHV).

 

So I am supposed to take your word because you supposedly work in the field and have a clean exhaust? Are you serious? And I never said for you to do it. I said show me a study done and backed by scientific evidence. Till then I will stick to what the US EIA says about octane and btu. Also can be found in the DOE website.

As for giving your vehicle the best doesn’t always pan out. You could put the best oil and fuel and if that vehicle has a mechanical part that was machined wrong, it’s going to fail. And as far as I know nobody has done a test on longevity with crap oil vs good oil or gas. So you can say that the best stuff will make your vehicle last longer but it doesn’t make it true. If your truck would have blown up ant 100k then there goes your argument for gas /oil. But since Toyota builds a good product those failures are very few. Go buy a new Chevy with the AFM and use the best oil and gas. I bet you that won’t stop the lifters from failing at the high rate they are. So since nobody knows the future, I will take the money I save on 87 and decent oil and put it towards things I can control.

 

Bruh may know some hydrocarbons, but don’t know jack about engines and performance.

 

The only reason I see that premium would have more 'oomph' would be if it doesn't have corn in it.

 

Here's something from a credible source for the premium side of the fence.

https://daptuning.com/faqs

quote:

---
Do I need to run Premium Fuel?
As we have reported with every truck we have tested on, 4.6L, 4.7L, 5.7L, all run best on 91+ octane whether they are completely stock with stock tune, or tuned. These engines pull 8-12 degrees of timing due to knock retard on 87 oct, 6-10 deg on 89oct, 2-6 deg on 91oct, and 0-2deg on 93oct. That is on a completely stock truck with factory tune.

If you care about the engine in your $35,000-$65,000 truck as you think you do, you wont run anything but premium in it weather you are tuned or not tuned.
---

 

As someone that hammers his engine for prolonged 4k rpm pulls up 8% grades towing 7,000 pounds running 87 octane - this is BS. I do live monitoring and see 38* timing advance and no knocking. I know the guy who sells tunes will say I’m wrong but that’s okay with me.

 

I'd be curious for someone to test timing utilizing one heat range down spark plug (same as what's called for on a blow 5.7) vs the warmer OE.

 

You would probably benefit from running the blower plugs on your rig running out here in AZ.

 

We use 87 to prime the drag boat.

https://youtube.com/shorts/srnStBuZ9-A?feature=share

 

Like AZ said, he does sell tunes. But to say that every 4.6-5.7 has had knock is a stretch. Even if true, I would say that the knock is in the upper rpm range where most people aren’t in 90+% of the time.

 

using premium gas to gain HP is just like CAI makes 15-20 wheel hp claim...

 

Yes. However, he also says:

If you care about the engine in your $35,000-$65,000 truck as you think you do, you wont run anything but premium in it weather (sic) you are tuned or not tuned.

 

The seller’s logic being - if he can convince someone they should pay a huge premium for fuel (see what I did there) anyway, they might just go ahead and get a tune since it won’t cost any extra in fuel over the life of the vehicle … he might even convince you the money saved from MPG - the tune will “pay for itself”.

Call me skeptical, but when someone stands to gain financially getting you to believe what they say - you better look closely.

 

Granted.

 

Well if you really cared about your $35-65k truck you wouldn’t tune it and race it. It’s a 6,000lb brick.

 

slow your roll there. Thems is fightin words

Blown, then tuned, smaller pulley, larger injectors, tuned again

and I use use ethel

y’all remember ethel gas?

 

Been there done that. 07 Silverado SS Maggie, small pulley, dual water to air coolers, LT headers, etc. $$$$. I sometimes want to SC the tundra so bad but then I see the $7500 price tag.

 

7500 won’t get you far

it’s $10k after the folks on this forum get done with you

 

Yeah I am all too familiar. The SC on the SS was $3200. By the time I did everything I was around $10k into it.

 

i have a little hot rod that needs a blower

but, jeez the prices these days

it’s a high compression 350. So it runs on premium too

I’m not to sure it gets 5mpg.

big ole demon carb on it