For the guys who think they get more power with 91 octane fuel

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Not sure why adding 113 octane ethanol to 110 octane non-ethanol alkylated gasoline yields an 87 octane blend. Pretty clear that ethanol was used as a cheap, taxpayer-subsidized octane booster that also reduces fuel economy due to less thermal energy per unit volume.

Higher octane fuel only performs better in engines that have high enough cylinder pressure to burn it. Whether be by compression ratio, turbocharger, supercharger, intercooler, or other means. Otherwise, a higher octane fuel without enough spark advance does not burn completely - producing more engine deposits.

Low octane pure gasoline is especially important for small gasoline engines with low compression ratios, such as Briggs & Stratton's (6:1 compression ratio, flathead, extremely sensitive to incomplete combustion buildup).

I worked for a major engine manufacturer, Onan. Also used Ford & GM Industrial engines. Then Cummins for diesels.
I am not a gas/fuel chemist, mad scientist, "Breaking Bad" type of guy, but I am only going by what these articles and people who own gas companies that I know do ...

Like I said, my friend in Georgia, her and her husband run gas companies and they bought 110 octane fuel, mixed it themselves and go the 87, 89 and 91 that the sold without having to actually buy the blended octanes already from the refineries ...

I think this is what's confusing right?

When you mix 10 percent 113 octane ethanol with 85 octane gasoline it increases the octane two points to the normal 87 octane most consumers use

I take or understand from that above that if you mix 113 octane gasoline with 10% ethanol with 85 octane you get the 87 which is the normal octane mos use ... that is how gas stations sell 87, 89 and 91 as they like .....

I have seen how some people on these forums are leery about certain gas stations selling 87 as 91 or 89 as 91 .... this is how they do it ... all that gas is actually raw 110+ octane to start off with, but adding that ethanol and what ever else they add drops it down to the 87 ... right?

I might be completely misunderstanding all this lol ..but that's how my brain is understanding this mumbo jumbo lol ....
 
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Correct me again,but if they're adding alkylate to fuel,which has a lower voialatilily rate then gasoline ,that would mean there's less actual BTU's per pound of fuel then a pound of fuel with-out it.Which leads me to think there's more alkylate added to the lower octane fuels,consequently they would have a lower production of energy in comparision,to the higher octane fuels with a smaller percentage of it.Which would explain why you notice a differance in power,less BTU's means less power production. So if that's the case ethanol really has nothing to do with it,at least in California.
Could very well be why Wilds ... all I know is that my truck on 89 ran like **** ... went back to the 91 and all is good .... I am no biochemist in gasoline, fuels and all this **** lol ... but something about 91 here especially from Chevron that my truck loves ... my corolla loves it and it's a 1993, all the cars in our family have only ever had 91 Chevron ... so does my wife's Lexus but hers requires premium anyways ...

I did mention this before in another post, our gasoline here in California is different from other states, I have only been to Arizona in the last 20 years and their Chevron is the same as California's .... so that can very well be why 89 octane drops my trucks power so much .. in reality by what you just described, it's probably low end 87 with maybe something like 15% or more ethanol ... I know I have seen some gas stations mention up to 20% ethanol, but those gas stations sell gas cheap as hell lol .. like $4 - $5 a gallon and you can tell when someone is running that cheap watered down gas lol because you can smell it coming out of their tailpipes..

AM/PM gas out here is the cheapest "quality" wise gas you can buy ... when someone uses am/pm gas out here you can tell right away no matter what grade they are using ... it smells horrible lol
 
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Correct me again,but if they're adding alkylate to fuel,which has a lower voialatilily rate then gasoline ,that would mean there's less actual BTU's per pound of fuel then a pound of fuel with-out it.Which leads me to think there's more alkylate added to the lower octane fuels,consequently they would have a lower production of energy in comparision,to the higher octane fuels with a smaller percentage of it.Which would explain why you notice a differance in power,less BTU's means less power production. So if that's the case ethanol really has nothing to do with it,at least in California.
Another thing Wilds ... Newsom doesn't want anyone being able to outrun the cops out here lol .. they want our vehicles to produce the least amount of power as possible ... that is why we can't legally add headers, tunes, an all that cool **** to our trucks ....

The fines for illegally tuned vehicles out here is ridiculous .... those that get away with it man I commend them for being able to lol ... What I would do to have my Ram with long tubes, an HP tune and everything else I could possibly add to it ...

My last tuned vehicle was a 91 Honda Civic hatchback back in 1998 ... it was impounded and the fines for everything that it was tuned on it totaled $17k .... I couldn't get my driver's license back until it was all payed and since the damn thing was sold at an auction they dropped the total to $8k after 2 years of battling it all out in court lol .....

California is straight up a Communist State lol ..... but oh well not much I can do right now ..
 

gofishn

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I have always said I am in California lol ....**** even my profile to the right says I'm in California ....
So, is it the Water, Biology , Nature or Nurture that make so many Californians wear Rainbow *******?

Positive side, the dark Brown Racing Stripes, on my Tighty ******'s, would be much less noticeable, on Rainbow colored ones.
Wouldn't have to soak them in 5 gallon buckets of Bleach, for 3 days, before washing.
 
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Wild one

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I am not a gas/fuel chemist, mad scientist, "Breaking Bad" type of guy, but I am only going by what these articles and people who own gas companies that I know do ...

Like I said, my friend in Georgia, her and her husband run gas companies and they bought 110 octane fuel, mixed it themselves and go the 87, 89 and 91 that the sold without having to actually buy the blended octanes already from the refineries ...

I think this is what's confusing right?

When you mix 10 percent 113 octane ethanol with 85 octane gasoline it increases the octane two points to the normal 87 octane most consumers use

I take or understand from that above that if you mix 113 octane gasoline with 10% ethanol with 85 octane you get the 87 which is the normal octane mos use ... that is how gas stations sell 87, 89 and 91 as they like .....

I have seen how some people on these forums are leery about certain gas stations selling 87 as 91 or 89 as 91 .... this is how they do it ... all that gas is actually raw 110+ octane to start off with, but adding that ethanol and what ever else they add drops it down to the 87 ... right?

I might be completely misunderstanding all this lol ..but that's how my brain is understanding this mumbo jumbo lol ....
I'm not sure about down south,but alot of the stations up here in Alberta only have 2 tanks,one is 87 and the other will have either 91 or 93/93 in the other tank,depending on their top grade fuel,and the 2 are mixed right at the pump to come up with the other octane levels
 

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I'm pretty sure they do. Most gas stations by me, the Eau Claire area, have 87 and 89 with 10% and 91 with no ethanol. I've seen a few kwik trips that on the 91 it says something like for recreational vehicles, collector cars, etc but not all of the kwik trips say that for their 91. Today I put in 91 octane at a Cenex and all the 91 pump said was no ethanol.
SE WI here, it's fairly random, a few BP stations, Woodman's, and a few Kwik Trips have E0 91 octane. No labels about restrictions for use.
 
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I'm not sure about down south,but alot of the stations up here in Alberta only have 2 tanks,one is 87 and the other will have either 91 or 93/93 in the other tank,depending on their top grade fuel,and the 2 are mixed right at the pump to come up with the other octane levels
That's pretty much how they do it here ... well the no name gas stations, they buy 110+ octane gasoline and mix it at the pump or before the pump in a mixing reservoir I think they call them ...
 

HEMIMANN

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What's really bizarre @CheechDogg.0n37s is California is kind of the home of the hot rod and performance engine culture. ****, Gale Banks is there, and Engine Masters.

I guess y'all gonna be running Tesla Coils from here on out. Up here we be makin' corn squeezin's and bean juice.
 
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What's really bizarre @CheechDogg.0n37s is California is kind of the home of the hot rod and performance engine culture. ****, Gale Banks is there, and Engine Masters.

I guess y'all gonna be running Tesla Coils from here on out. Up here we be makin' corn squeezin's and bean juice.
Oh dude, they are all allowed to do whatever the fawk they want .. rules only apply to certain people lol ....

I don't see it bizarre at all ... it's all about money ... they scratch each others backs ....
 
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We have a small gated community between Moreno Valley and Elsinore and Temecula called Canyon Lake, they are allowed to do whatever they want in there ... you always see Banks, Metal Mulisha, tons of offroad and water craft companies in there tearing it up, it's a small version of Lake Havasu in the summer lol .. they use so much high octane fuel to fire up those speed boats in there it's insane dude ...and no one talks about it because unless you live in there or you are a brand company name, you are not allowed inside ... not even outside cops are allowed inside during certain times of the summer .... honestly it's a damn swingers paradise with a bunch of drunk police officers, fireman, lawyers, you name it ... homes in there easily in the 5 million range ..

Anyways, that is one place where you can easily see how privileged really looks like ... I know this went off topic but rules only apply to certain people here lol
 

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Sorry, off topic, but some of you might find this interesting:


Regards,
Dusty
2019 Ram 1500 Billet Silver Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33-gallon fuel tank, factory dual exhaust, 18” wheels. Build date: 3 June 2018. Now at 80209 miles
 
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Been using Billet Technology catch cans for many years on many vehicles!
Best damn positive maintenance item one can install.
Keeping the TB and the intake plenum nice and clean is a huge benefit!
I got the UPR catch can from @Nick@GotExhaust ...he recommended it @ram1500rsm recommended it and a few others... so far it has done it's job as far as I am concerned ...I check it every 2 weeks and dump what's in there ...

I color matched mine though ...

1668449051763.png
 
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HEMIMANN

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Everybody keep in mind there isn't a breather coalescer for the 6.4 Hemi. They buried the breather return under the intake manifold. Supposedly an "improvement" over the original 5.7 Hemi architecture, for some reason. Maybe stays hotter for less depositing?
 

Nick@GotExhaust

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Catch cans are a great low cost mod to keeping your engine better maintained. The 1st time you empty the can you can tell it was money well spent!

For anyone interested we have them listed here
 

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I got the UPR catch can from @Nick@GotExhaust ...he recommended it @ram1500rsm recommended it and a few others... so far it has done it's job as far as I am concerned ...I check it every 2 weeks and dump what's in there ...

I color matched mine though ...

View attachment 506879
Same except I went with an ebay special with upgraded hoses and mounted it to the airbox. I should empty it tomorrow, it's been a bit.
 

HEMIMANN

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Correct me again,but if they're adding alkylate to fuel,which has a lower voialatilily rate then gasoline ,that would mean there's less actual BTU's per pound of fuel then a pound of fuel with-out it.Which leads me to think there's more alkylate added to the lower octane fuels,consequently they would have a lower production of energy in comparision,to the higher octane fuels with a smaller percentage of it.Which would explain why you notice a differance in power,less BTU's means less power production. So if that's the case ethanol really has nothing to do with it,at least in California.

I understood the alkylation adds a little more energy per unit volume precisely because it isn't as volatile.

It adds an alkyl group, which is denser, to the base hydrocarbon chain.
 
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