Ford Mustang Forum banner

1 - 20 of 35 Posts

·
Registered
Joined
·
99 Posts
Discussion Starter #1
Ok so I need some input, I live colorado where 91 oct is the norm and 93 is harder to find than bigfoot, so I was thinking of getting a 93 octane tune from bama and running 100 octane at the track only. Would I see any performance gains? Or would it cause trouble on a n/a setup and nitrous setup? Just trying to squeeze every hp out of the pony .
 

·
Registered
Joined
·
1,399 Posts
You'd lose performance actually.

It would be like using 93octane on the stock 87 tune. A friend from this fourm has recently went from a 91 tune (that they sent him by mistake) with 93octane gas to the 93 tune and he said there was a noticable difference.

When I went back to the stock tune and had a full tank of 93 octane my car was sluggish like crazy!

Maybe with the new system where you can run 87 or 93 and the computer will adjust.
 

·
Registered
Joined
·
1,652 Posts
Oak Lawn Chris is correct. You'll lose performance using 100 octane gas with a 93 tune, because there will be incomplete combustion.

Another option is to add 3.5 gallons of 100 octane to 12.5 gallons of 91 octane to get a 93 octane mix.
 

·
Registered
Joined
·
1,399 Posts
After I posted it I saw that he was running Nitrous and wasn't sure if that would change anything. Thanks ski for confirming.
 

·
Registered
Joined
·
2,541 Posts
Or get a 100 octane nitrous tune for the track and a 91 octane tune for the street
 

·
Registered
Joined
·
1,749 Posts
actually, you wont see a performance increase or decrease. a fuels octane rating is simply a rating of its resistance to pre-detonation. higher rated fuels are less like to pre-ignite or in laymans terms cause the engine to "ping". If you have a 93 tune, as long as you run 93 or better your good, but you wont get more performance with a higher octane fuel.

actually, i have dougs 91 octane torque tune and ive been running 89 in it for 3 years now unless im going to the track and know i will be pushing the car really hard. for everyday street driving i use 89 cuz its cheaper, i havent heard a single ping running 89 with the 91 tune. in the winter when its really cold, i do go back to 91 too.

simply put, as long as shes not pinging, obviously the octane rating is ok.


to debunk another common myth, higher octane fuel is not cleaner either...:winks
 
B
Joined
·
0 Posts
One other thing to consider also is most racing fuels are oxygenated. This means oxygen entering the combustion chamber which has not been acounted for by the MAF which could cause a lean issue.

I've been mixing my fuels for the last couple years now with no problems. Just keep a log book and update it everytime you fill up.
 

·
Registered
Joined
·
1,399 Posts
actually, you wont see a performance increase or decrease. a fuels octane rating is simply a rating of its resistance to pre-detonation. higher rated fuels are less like to pre-ignite or in laymans terms cause the engine to "ping". If you have a 93 tune, as long as you run 93 or better your good, but you wont get more performance with a higher octane fuel.

actually, i have dougs 91 octane torque tune and ive been running 89 in it for 3 years now unless im going to the track and know i will be pushing the car really hard. for everyday street driving i use 89 cuz its cheaper, i havent heard a single ping running 89 with the 91 tune. in the winter when its really cold, i do go back to 91 too.

simply put, as long as shes not pinging, obviously the octane rating is ok.


to debunk another common myth, higher octane fuel is not cleaner either...:winks
Actually, I think you're wrong. Speaking from personal experience, I've noticed less performance when using higer octane, as have many others. Cars run a bit more sluggish. As for you running 89 on a 91 tune, maybe the tune is conservative.

I dont have any scientific proof, just how the cars I've used have felt to me.
 

·
Registered
Joined
·
1,749 Posts
I stand by my post. Ive researched this before for personal knowledge. Everything I find is the same as this



From Discovery channel "How Stuff Works":

first line tells it all....


The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, it causes knocking in the engine. Knocking can damage an engine, so it is not something you want to have happening. Lower-octane gas (like "regular" 87-octane gasoline) can handle the least amount of compression before igniting.
The compression ratio of your engine determines the octane rating of the gas you must use in the car. One way to increase the horsepower of an engine of a given displacement is to increase its compression ratio. So a "high-performance engine" has a higher compression ratio and requires higher-octane fuel. The advantage of a high compression ratio is that it gives your engine a higher horsepower rating for a given engine weight -- that is what makes the engine "high performance." The disadvantage is that the gasoline for your engine costs more.







Im sorry, but I fail to see how having a fuel that can be compressed more will affect performance UNLESS you ARE compressing it more.


This also explains the biggest reason why diesel fuel wont burn in a gasoline engine, a regular gas engine cant compress the fuel the required 25.1 ratio to ignite it.



on another note, if your buying any of that s--ty 10% ethanol crap that some stations are selling, your gasoline engine doesnt have enough compression to ignite that either, which means 10% of the fuel you pump is just going out the exhaust, which is why i wont put that crap in my car. .:nono: (not too mention my father whos been in auto parts for 30 years says he is selling more fuel pumps than ever since that stuff hit the market. He says its eating away at all the pumps internal seals)



EDIT: the only exception i can think of is if you put in a really high octane like 105 or higher, then your engine would have a harder time igniting it. but any fuel 87 - 93 octane should still be well within the range for igintion. if performance did decrease, I seriously doubt it would be a measurable amount.
 

·
Registered
Joined
·
1,399 Posts
I stand by mine as well. I'm speaking from my experience with my cars now. From everything I've read online, they say some engines can have less performance and some it wont really effect.

To the OP, I would say do NOT use the 100 octane on a 93 tune! There is no benefit and it CAN actually hurt. Not saying it will, but it can. I noticed using 93 on the stock tune that my car was more sluggish. Maybe it was in my head, but I had no preconcieved ideas about it at the time.

You said you wanted to squeeze every HP out of it, have them change the tune for the racing fuel. Is this an option?

You can always swap out the jets and run a 125 shot too!:winks
 

·
Registered
Joined
·
1,652 Posts
Below is an interesting article on regular vs. premium gas.
Please take note of the quote from Lewis Gibbs, consulting engineer and 45-year veteran at Chevron Oil Company, and chairman of Technical Committee 7 on Fuels, part of the Society of Automotive Engineers (SAE) Fuels & Lubricants Council:
"Premium, in fact, sometimes is worse fuel than regular. It resists knock because it's harder to ignite than lower-octane fuels. As a result, some engines won't start as quickly, or run as smoothly on premium."
USATODAY.com - Why use premium gas when regular will do?

Also, E10 is a mixture of ethanol and regular gasoline in ratios that are designed to equal the octane ratings listed at the pump.
Thus, an engine designed to operate with a specific octane gasoline should not have any problems with incomplete combustion if the correct E10 octane is selected.
However, I agree that E10 is crappy fuel, not only because it can damage critical fuel system parts, but it also reduces gas mileage due to ethanol's lower energy content per unit volume, and it has a short shelf life which causes it to easily gum up fuel systems, e.g., my lawnmower.
 

·
Registered
Joined
·
1,749 Posts
To the OP, I would say do NOT use the 100 octane on a 93 tune! There is no benefit and it CAN actually hurt.

ahh, at least we have found some common ground. I totally agree with you on that one, sir.:winks definately no benefit.


main thing that gets on my nerves is the gas companies market premium fuel so that misinformed people think that it is cleaner and will get better performance or economy from simply pumping it in their gas tank. there is nothing "premium" about it. Its just higher octane.

bottom line - premium fuel is a fuel for performance engines that require it. It is NOT a performance fuel.:winks
 

·
Registered
Joined
·
1,749 Posts
Also, E10 is a mixture of ethanol and regular gasoline in ratios that are designed to equal the octane ratings listed at the pump.
Thus, an engine designed to operate with a specific octane gasoline should not have any problems with incomplete combustion if the correct E10 octane is selected.
However, I agree that E10 is crappy fuel, not only because it can damage critical fuel system parts, but it also reduces gas mileage due to ethanol's lower energy content per unit volume, and it has a short shelf life which causes it to easily gum up fuel systems, e.g., my lawnmower.

my thinking exactly. 10% ethanol means 10% reduced fuel economy. if you do the math, that nickel you saved at the pump wont be worth it.


and that is an interesting article
 

·
Registered
Joined
·
1,652 Posts
I was actually addressing your inaccurate comment that a gasoline engine does not have sufficient compression to ignite E10.

Also, I'm retracting my comment in my initial post "You'll lose performance using 100 octane gas with a 93 tune, because there will be incomplete combustion", and modifying it to "You may lose performance using 100 octane gas with a 93 tune, because there may be incomplete combustion".
 

·
Registered
Joined
·
1,749 Posts
I was actually addressing your inaccurate comment that a gasoline engine does not have sufficient compression to ignite E10.

actually, i said it doesnt have enough to ignite ethanol. Not ethanol in gasoline. (E10) E10 will burn, just not completely. if you pump pure ethanol in your tank, you wont go nowhere. in other words, the 10% ethonal in E10 wont burn completely, and not at a temp to provide any power to the engine, there for is basically 10% waste. you need COMPLETE combustion for optimal performance.

i also will retract my statement on the performance decrease with the higher octane and agree with you on your statement that "you may lose performance." it sure wont increase.
 

·
Registered
Joined
·
1,749 Posts
This study showed E10 improves combustion vs. regular gasoline.

http://www.ilot.edu.pl/KONES/2003/1-2/26.pdf

and this one says E10 gets 1% less....

E10 ethanol achieves only 1% less fuel economy than E5: study : Biofuels Digest


and this one a member on some forum did and got 7.8% less with E10 over regular


E10 vs E0 MPG study - Bob Is The Oil Guy

here is another that says 1.5% drop

Energy Answers: ACE Study shows minimal mileage drop for E10

point being my friend, is that we could debate this all day long, as i ran across just as many "studies" that showed E10 made no difference.

its for this exact reason that E10 fuel usage has been in debate all over the country and in fact the world since its introduction.

you pretty much just have to decide what you believe.



for me, mileage isnt the real reason i dont use it anyway.

fuel pumps are expensive! not too mention a PITA to change.
 

·
Registered
Joined
·
1,749 Posts
funny, you said:

it also reduces gas mileage due to ethanol's lower energy content per unit volume


I said:

the 10% ethanol in E10 wont burn completely, and not at a temp to provide any power to the engine, there for is basically 10% waste


we are so busy debating, we failed to realize we are debating something we already previously agreed on.:heha:


To the OP - sorry man, i didnt mean to turn this into an E10 thread
 

·
Registered
Joined
·
1,652 Posts
I believe we have what's called a proverbial apples and oranges situation.

I'm referring to the % combustion of E10 vs regular gasoline, and you appear to be referring to the mpg of E10 vs regular gasoline.
The article I linked indicates that E10 burns more completely than regular gasoline, and your linked articles indicate E10 gets less mpg than regular gasoline.

However, the reduced mpg of E10 is due to its lower energy content than regular gasoline. Not because it combusts less efficiently.
 

·
Registered
Joined
·
37 Posts
Ok so I am here to tell you guys all about Ethynol. I have many E-85 stations all over my area and love it to death. Sure it has some drawbacks namely decreased ecomony but its over a dollar cheaper and that 10-15% ecomomy loss still saves me money in the end. Lets do some math. I have a 2004 Explorer Sport Trac which on regular gas costs me $87 to fill 24 gallon tank at $3.65 a gal. Now I can get maybe 400 miles for that money if I drive all highway with the cruise set. Now I can get for that same $87 dollars a full tank of Ethyl and still fill three additional 5 gal cans for the same price. Now for that $87 dollars I can go 575 miles! While my MPG is less my dollars spent per mile is less which in the end is money saved. Also when I change my oil after 5,000 miles(yeah you read it right) the oil comes out just as clean as it went in. I had a Cat oil analysis done once and they found no impurities what so ever. Now more about how you said a tank of Ethyl wont run in your car. You are so wrong!
Alcohol is flamable and will burn. It may not burn well and your car may run pretty bad due to programming issues but it will none the less burn. The only exception is trying to run it in the winter you may have starting problems in a non flex vehicle...lol. I ran it in my Jeep Cherokee for an entire summer once to prove the guys in my Jeep Club wrong. I think that this fuel is misunderstood and full of myths started by the oil companies who dont want you to change your ways and keep you under their thumb paying their prices etc. Still dont believe me? Here is a link for a study some guys did a while back.

YouTube - ‪E85 Ethanol Does not harm Non-FlexFueled Engines‬‏. Sorry about the poor sound quality.

I really like E-85 because it has 105 octane and with the right tuning you can make it work in just about any vehicle and have the benefits of high octane without paying the race gas prices.

BTW the reason you cannot find 93 octane in Colorado is because the altitude is so high and the air is so thin that your ressistance to detonation is greater naturally. Thats why everywhere else in low elevation has 87 octane for the regular and you guys have 85 octane.
 
1 - 20 of 35 Posts
Top