octane in my svx

[oab_au]

Originally Posted by Cam

Most engines probably have suffered from a slight compression loss, like stated above. Also, the air density matters as well. High elevations will take less air into the cylinder making the car run rich. So high elevation cars should run fine on slightly lower octanes as well.

I think the Mass Air Flow sensor, will take care of that.

Harvey.

[Cam]

Originally Posted by oab_au

I think the Mass Air Flow sensor, will take care of that.

Harvey.

To a certain degeree. This is just speculation, but the injectors can only open and close so quickly. There is a point where they would not help but run rich. (that could possibly be a very extreme situation, though)

[svxfiles]

OK,
Today's gasoline is not the same gasoline that we had back in 1991-1997!
The octane might have close to the same numbers, BUT it now has less BTUs, thanks to ethenol!
Ethenol=alcohol
“On a volumetric basis ethanol yields 83,910 BTU’s/ gallon of thermal energy from combustion.
Gasoline yields 124,800 BTU’s/ gallon of thermal energy."
It takes more fuel to get the same power out of a gallon of today's C.R.A.P.
Citizen/Required/Alcohol/Petrolium!

Sure, adding alcohol lowers combustion temperatures, but the power falls off.
If I wanted less power I'd drive a Neon! Or a Taurus or some other piece of crap.
Cheaply Replicated Automobilelike Product!
And now THEY are raising the ethenol to 20%!
Comrade, Reality Ain't Pretty!

[92 SVX]

Originally Posted by Huskymaniac

Maybe we should run regular and add Toluene or Xylene. It would keep the fuel system clean and boost the octane.

I have done that, its cheaper to buy premium. Both Toluene and Xylene are over $15 per gallon, even more expensive if you buy smaller quantities. To get even 1 octane rating higher you need 1 gallon per tank

Originally Posted by Cam

I wouldnt do that without buying some seals and dumping them into a bucket with those chemicals. Probably not a good idea. I heard of someone using acetone to get better fuel economy. But that's the kind of thing you do with a rental vehicle.

Toluene and Xylene will not harm your seals, they are already in gasoline Acetone however could in large enough quantities though I have used that in small doses with minimal improvements so I stopped.


http://www.gnttype.org/techarea/misc...explained.html

This is a very good write up of octane and toluene

[Bonestock]

I run mid grade nearly all the time in my car and only run premium once every 3 fill ups if I remember. Unless you are running the car hard or loading (high load, low RPM) its not gonna matter IMO.

YMMV

BTW this is coming from a guy that was fanatical about buying only Shell v-power and running only the finest PAO oils. All that additional expense added up to NOT, NADDA not a damn thing except less $$$ in my pocket.

[1986nate]

I have proven that my gas mileage will suffer under highway cruising with lower octane. I got 30.9 with 93 octane with 10% ethanol blend from here to about Indianapolis where they had 92 octane, got about 29.5 so slight changes in driving conditions could apply there, but every time that I have put 91 octane in , either with or w/o ethanol mix, the mileage drops to about 24-26 hwy mpg's...

These were all on my laguna fwd SVX. Considering 93 octane is generally found here for 16-20 cents more than regular, I'll stick to 93 octane.

[Gamesy]

whats everyone's opinion on octane booster to help offset the ethanol?

[92 SVX]

Originally Posted by Gamesy

whats everyone's opinion on octane booster to help offset the ethanol?

be careful and do your research on the booster, I believe, IMHO most are garbage.
I have tried the NOS which is supposed to raise octane about 60 points, or i think about 3 octane though I could be wrong on that number. could be 6 octane anyway I think it does what its supposed too. not a bad price at just over $10 a bottle.
Here is a good place too look
http://www.octane-booster.com/
And it looks like I was mixing nos regular and nos racing regular is 30 points or 3 octane and racing is 60 points or 6 octane.

Here is a great place to start researching and learning
http://www.europeancarweb.com/tech/0...ted/index.html

[LetItSnow]

Originally Posted by 92 SVX

While it looks impressive subbieatnz is in new zealand and they rate the octane differently, ...

I figured as much, but taken out of context, it's still a nice wish. I've got a legitimate reason.

Originally Posted by 92 SVX

Toluene and Xylene will not harm your seals, they are already in gasoline Acetone however could in large enough quantities though I have used that in small doses with minimal improvements so I stopped.

Naturally, this leaves me wondering about Torco's additive, which should be good for a solid kick in the pants.

[StatGSR]

Originally Posted by Gamesy

whats everyone's opinion on octane booster to help offset the ethanol?

dude, ethanol is the octane booster... Ethanol has a octane rating of about 120...

I just prefer to run non-ox in anything that required premium (no ethanol added 91)


Also increasing the octane doesn't increase the energy in fuel, it prevents it from detonating
The required octane for a car is based on the compression ratio of an engine, the CR essentially determines the efficiency of an engine so unless you change it, (with new pistons or adding some form of forced induction which effectively changes the CR of the engine as it builds boost), then there is no reason to increase the octane of your fuel. reversely, that's why higher octane race fuels or ethanol (E85) works so well on turbo vehicles, you can raise up your boost substantially while still preventing detonation<--Engine Killer


Also, Octane Ratings across the world...
http://en.wikipedia.org/wiki/Octane_rating

[92 SVX]

Originally Posted by StatGSR

dude, ethanol is the octane booster... Ethanol has a octane rating of about 120...

I just prefer to run non-ox in anything that required premium (no ethanol added 91)


Also increasing the octane doesn't increase the energy in fuel, it prevents it from detonating


Also, Octane Ratings across the world...
http://en.wikipedia.org/wiki/Octane_rating

yes but ethanol has a lower btu, and octane booster with at least as high of btu if not higher then gasoline is much more preferable.
Its too bad ethanol is added to all grades of gasoline in most places, including where I live. means if it were possible to strip the ethanol out we would most likely be left with a lower octane grade of fuel. In the case of the 93 octane it might be 91.8 or something, the actual number I do not know.

[StatGSR]

I'm very aware of that, also please see my edit.

I'm just saying, its not a higher octane that you need to have a greater energy density in your gasoline.

Like i said, the best you can get is non-oxygenated gas if you can find it near you.


Adding ethanol takes crap gas to an acceptable level that won't destroy an engine, but on the other hand, doesnt create as much energy when burnt either.

[kwren]

Originally Posted by svxfiles

OK,
Today's gasoline is not the same gasoline that we had back in 1991-1997!
The octane might have close to the same numbers, BUT it now has less BTUs, thanks to ethenol!
Ethenol=alcohol
“On a volumetric basis ethanol yields 83,910 BTU’s/ gallon of thermal energy from combustion.
Gasoline yields 124,800 BTU’s/ gallon of thermal energy."
It takes more fuel to get the same power out of a gallon of today's C.R.A.P.
Citizen/Required/Alcohol/Petrolium!

Sure, adding alcohol lowers combustion temperatures, but the power falls off.
If I wanted less power I'd drive a Neon! Or a Taurus or some other piece of crap.
Cheaply Replicated Automobilelike Product!
And now THEY are raising the ethenol to 20%!
Comrade, Reality Ain't Pretty!

As usual, SVXFILES is right on. The feds never get anything right. The introduction of 10% ethanol reduced the gas mileage by 10%. 20 % ethanol will reduce the mileage by 20%.
Translation... ethanol is totally worthless! I believe ethanol is also disaster for our engines as well.

Keith

[jeffs92svx]

I use 93 in every car I drive. I get better mileage, better power and a cleaner burning engine.

[StatGSR]

Originally Posted by kwren

Translation... ethanol is totally worthless!

actually i couldn't disagree more.

while i don't appreciate what it does when mixed with for pump gas, E85 at a pump has huge benefits for making little engine's make gobs of power.

in my town, all the guys with the fastest turbo imports are all corn fed. race fuel octane levels and prices cheaper than gas is pretty sweet, only down side for most of those cars is they are not so good for road tripping across the country any more and obviously they get pretty lousy mpg, but for what they use em for there really isn't a better fuel around.

honestly, if a manufacture built an engine to run purely on ethanol (not this BS idea of flex fuel) those would probably some of the most impressive motors on the market, stuff like 1.3 liter I4s, turbo, direct injection... could still = 200+hp and over 30+ mpg

sorry, i just don't believe e85 is the worst thing ever when use appropriately.