Addicted to octane (good octane boosters?)

[B6_Rakete]

I pumped a tank of Sunoco 100 octane gas ($7.49/gal) into the S4 the other day when I was running on fumes to see what the stock computer would make of it. I was really surprised at the difference, the car was *much* faster as compared to running on the normal "Premium" 91 octane crap we get here in CA. It felt like the car had another 20-30HP easy, which I really didn't expect without a special APR/GIAC/Whatever tune.

I was desperate to maintain the extra HP tonight while at Shell filling up on crap and ended up pouring in some STP Octane Booster (with no advertised octane increase estimates on the bottle or on the website: http://www.stp.com/fuel_octane.html) that they were selling at the station for $5.83. The whole bottle was supposedly good for 15 gallons of gas.

Anybody know which octane booster gives the highest octane bump without clogging/burning/choking the cats?

[ngng]

you're tricking yourself. you should run the lowest octane possible where your engine doesnt knock

[PenguiN]

yea what he said ^

[Ike]

Yeah, most of what you felt was probably placebo. However, if you're convinced that you need better octane don't waste your money on the silly little things from the gas station. Go get yourself a few jugs of toluene and add a gallon or two every time you fill up. Just be careful of the paint ;)

[B6_Rakete]

you're tricking yourself. you should run the lowest octane possible where your engine doesnt knock

Wow, you are very confused.

Educate yourself:
http://www.youtube.com/watch?v=dDHwCWdrtdg

http://en.wikipedia.org/wiki/Octane_rating

Excerpt: "However, burning fuel with a lower octane rating than required by the engine often reduces power output and efficiency one way or another. If the engine begins to detonate (knock), that reduces power and efficiency for the reasons stated above. Many modern car engines feature a knock sensor – a small piezoelectric microphone which detects knock and then sends a signal to the engine control unit to retard the ignition timing. Retarding the ignition timing reduces the tendency to detonate, but also reduces power output and fuel efficiency."

[B6_Rakete]

yea what he said ^

And you as well.

[B6_Rakete]

Go get yourself a few jugs of toluene and add a gallon or two every time you fill up. Just be careful of the paint ;)

I think you're right, it seems toluene might be the best option:

http://www.elektro.com/~audi/audi/toluene.html

[CHECKERED]

I pumped a tank of Sunoco 100 octane gas ($7.49/gal) into the S4 the other day when I was running on fumes to see what the stock computer would make of it. I was really surprised at the difference, the car was *much* faster as compared to running on the normal "Premium" 91 octane crap we get here in CA. It felt like the car had another 20-30HP easy, which I really didn't expect without a special APR/GIAC/Whatever tune.

I was desperate to maintain the extra HP tonight while at Shell filling up on crap and ended up pouring in some STP Octane Booster (with no advertised octane increase estimates on the bottle or on the website: http://www.stp.com/fuel_octane.html) that they were selling at the station for $5.83. The whole bottle was supposedly good for 15 gallons of gas.

Anybody know which octane booster gives the highest octane bump without clogging/burning/choking the cats?

Same exact experience here.
I mixed 5.5 gallons of 100 octane from 76
With 11.5 gallons of 91 according to my calculation, That makes almost 94 octane.
Car feels noticeably faster and more responsive, I hooked up a my G-Tech SS and measured 0-60.
Best I got was 5.44
After my next refill with just 91, I will run again to see if there are any difference in performance, and post my results.

[Justincredible]

With the Cally craptane you are definitely going to see a difference with 100. I see correction in timing and I use 93. Our 93 is WAY better than your 91.

As for the power in a bottle
http://www.youtube.com/watch?v=2jbcCr2ll3c&NR=1


toluene is good but If you can find E85 that is much better for what you are doing. E85 should be coming to cally soon. With 109oct rating it is a good mixer. NEVER use it as a standard fuel and NEVER mix more then 20% but that should be a good option in the future

[WhippeD]

would be 100x better if you have the appropriate tune/software for it though

[37doc]

If your running 100LL (blue/avgas) better be carefull , you can burn up your valves.......

[ngng]

Wow, you are very confused.

Educate yourself:
http://www.youtube.com/watch?v=dDHwCWdrtdg

http://en.wikipedia.org/wiki/Octane_rating

Excerpt: "However, burning fuel with a lower octane rating than required by the engine often reduces power output and efficiency one way or another. If the engine begins to detonate (knock), that reduces power and efficiency for the reasons stated above. Many modern car engines feature a knock sensor – a small piezoelectric microphone which detects knock and then sends a signal to the engine control unit to retard the ignition timing. Retarding the ignition timing reduces the tendency to detonate, but also reduces power output and fuel efficiency."

you probably have a electric turbo too.

"Are you tempted to buy a high octane gasoline for your car because you want to improve its performance? If so, take note: the recommended gasoline for most cars is regular octane. In fact, in most cases, using a higher octane gasoline than your owner's manual recommends offers absolutely no benefit. It won't make your car perform better, go faster, get better mileage or run cleaner. Your best bet: listen to your owner's manual."

http://www.ftc.gov/bcp/edu/pubs/cons...tos/aut12.shtm

[b spot]

Wow, you are very confused.

Educate yourself:
http://www.youtube.com/watch?v=dDHwCWdrtdg

http://en.wikipedia.org/wiki/Octane_rating

Excerpt: "However, burning fuel with a lower octane rating than required by the engine often reduces power output and efficiency one way or another. If the engine begins to detonate (knock), that reduces power and efficiency for the reasons stated above. Many modern car engines feature a knock sensor – a small piezoelectric microphone which detects knock and then sends a signal to the engine control unit to retard the ignition timing. Retarding the ignition timing reduces the tendency to detonate, but also reduces power output and fuel efficiency."

You don't even understand what you just posted. That means if you go and fill with 89 your car will be slower. Big surprise. Higher octane gas has less energy per unit of volume than lower octane gas. Unless you have the compression/timing to require it, there is no point. You have the compression/timing for 91, not 100.

I also love how your body is such a finely tuned instrument you know it was "20-30 hp"

[drew]

i used to mix some octanium with pump 100 in my 911tt with good results. however that car had a race file that took advantage of higher octane.

http://www.octaniumpower.com/

[RAudi Driver]

someone just wasted theirmoney. $7.49 per gallon. your car will not benefit from the extra octane. lowest octane without activating the knock sensor is the best.

[bhvrdr]

You don't even understand what you just posted. That means if you go and fill with 89 your car will be slower. Big surprise. Higher octane gas has less energy per unit of volume than lower octane gas. Unless you have the compression/timing to require it, there is no point. You have the compression/timing for 91, not 100.

I also love how your body is such a finely tuned instrument you know it was "20-30 hp"

Actually if you look at any of the articles out there that put cars on dynos with different octanes, all the cars gained power with the higher octane, but the articles consider the gains not very significant so they go on to advise people to use the lowest octane recommended. Even so, in many of the articles as much as 2% and 5% gains are seen. That is the same gains seen spending $1000 on an exhaust or $600 on a chip so adding the 15 cents per gallon would be a very smart buy.

Suggesting the S4 is only timed for 91 octane means you havent run timing logs on the car. It pulls back as much as 8 degrees of timing on high quality shell v-power 93 octane. Most all cars built after around 1996 have relatively sophisticated knock management systems that will allow folks to take advantage of a bit more octane (say, up to 98 or so). Sure a race file would allow for more.

cheers! mike

[GotRS?]

And Mike closes yet another misunderstood subject. Thank you.

[...Mark...]

And Mike closes yet another misunderstood subject. Thank you.

How is this closed?

[Rodknock]

I also love how your body is such a finely tuned instrument you know it was "20-30 hp"

You dont ever butt dyno your car?

[Rodknock]

I also love how your body is such a finely tuned instrument you know it was "20-30 hp"

Some peoples butt dynos are better than others!

[B6_Rakete]

you probably have a electric turbo too.

Impressive grammar.

The excerpt above is probably talking about older cars with carb's/less sophisticated engine management setups that are tuned to only use a narrow range of octane effectively. Keep putting in that 87 octane Arco crap in your car, you probably couldn't tell the difference anyway.

[Dompiece]

If your running 100LL (blue/avgas) better be carefull , you can burn up your valves.......

^i was going to try some, but I don't want to break anything. Is this really somthing that can happen?

[ngng]

Impressive grammar.

The excerpt above is probably talking about older cars with carb's/less sophisticated engine management setups that are tuned to only use a narrow range of octane effectively. Keep putting in that 87 octane Arco crap in your car, you probably couldn't tell the difference anyway.

oops, my bad. a instead of an. when you don't have a valid argument, minus whale go after lazy typing! rite?

nobody said put acro in your gas tank. my argument is our vehicle will not benefit from 100 octane race fuel, STOCK. as a master of comprehension, i figured you'd understand taht.

for a guy getting his panties in a twist about octane, you have quite a few posts showing your ignorance.

[nimski62]

I just put a tank of ethanol in my car... supposed to run at 104 octane. I DEFF noticed some more punch, but then again i could be absolutely wrong. I did only one tank bc my mechanic recommended it to clean out the injectors a bit (alcohol).. BUT i did get Bank 1 and Bank 2 running LEAN codes, not good..

[bhvrdr]

How is this closed?

Good point. I got off track to the original question which was regarding what octane booster to use.

My opinion is to find some real unleaded race fuel.

But, if for some reason that is not possible, maybe this article will help a bit...

http://www.europeancarweb.com/tech/0...ted/index.html

IIRC, there were some errors in that article in their math but I havent read it in a long time so I'd have to go back through it again. Either way, it's not a terrible article.

cheers! Mike

[B6_Rakete]

nobody said put acro in your gas tank. my argument is our vehicle will not benefit from 100 octane race fuel, STOCK. as a master of comprehension, i figured you'd understand taht.

Whether it was a +2 or +5 increase in octane rating that the car was able to take advantage, I'm not sure. My original point was that the increased octane did make a difference so don't tell me it didn't. It could also be the that the normal summer formula we have to run here in CA is more power sapping than I expected. Either way, the difference was significant.

[B6_Rakete]

oops, my bad. a instead of an. when you don't have a valid argument, minus whale go after lazy typing! rite?

For someone with a signature describing the difference between "you're" and "your", you should be setting a better example.

[charliemike]

I don't bother with all that nonsense. I just make sure I'm buying gas without ethanol in it :)

[VVG]

I pumped a tank of Sunoco 100 octane gas ($7.49/gal) into the S4 the other day when I was running on fumes to see what the stock computer would make of it. I was really surprised at the difference, the car was *much* faster as compared to running on the normal "Premium" 91 octane crap we get here in CA. It felt like the car had another 20-30HP easy, which I really didn't expect without a special APR/GIAC/Whatever tune.

I was desperate to maintain the extra HP tonight while at Shell filling up on crap and ended up pouring in some STP Octane Booster (with no advertised octane increase estimates on the bottle or on the website: http://www.stp.com/fuel_octane.html) that they were selling at the station for $5.83. The whole bottle was supposedly good for 15 gallons of gas.

Anybody know which octane booster gives the highest octane bump without clogging/burning/choking the cats?

Two things here:

1. Octane boosters add such a small volume of high octane product that it does very little to a full tank of gas. Adding a quart of 108 octane booster to 16 gallons of 93 octane fuel, for example, will raise the octane to about 93.3.

2. Whether or not fueling up with real 100 octane fuel will yield a benefit all depends on whether the ECU is engineered to be able to advance timing and/or alter air:fuel ratios based on the use of 100 octane. The burning of 100 octane will change the the signal coming from the oxygen sensors. If the ECU can adapt and respond to the altered inputs in a power producing manner, you will see a gain. If, however, it won't advance timing any more than what is seen with 93 octane, than adding 100 octane will do nothing.

It would appear that the S4, and certainly the RS4 are both capable of advancing timing with 100 octane beyond the level of what is seen with the burning of 93 octane.

[RAudi Driver]

Two things here:

1. Octane boosters add such a small volume of high octane product that it does very little to a full tank of gas. Adding a quart of 108 octane booster to 16 gallons of 93 octane fuel, for example, will raise the octane to about 93.3.

2. Whether or not fueling up with real 100 octane fuel will yield a benefit all depends on whether the ECU is engineered to be able to advance timing and/or alter air:fuel ratios based on the use of 100 octane. The burning of 100 octane will change the the signal coming from the oxygen sensors. If the ECU can adapt and respond to the altered inputs in a power producing manner, you will see a gain. If, however, it won't advance timing any more than what is seen with 93 octane, than adding 100 octane will do nothing.

It would appear that the S4, and certainly the RS4 are both capable of advancing timing with 100 octane beyond the level of what is seen with the burning of 93 octane.

well put. I don't think that our cars can benefit from the added octane. sure they can retard timing but i don't think that they are programmed to advance it past what they are set at.

[Justincredible]

The cars will add timing. If you log the car you will see (or at least I did) on 93oct. about 6deg of correction. Putting in a better grade gas or more octane 0 correction. What dose this mean?

Well If the car has 6deg of correction on 93 and no correction on 100. This means your car just GAVE it self 6deg of added timing. Or the car ADDED timing.

But if you see no correction on 93 adding 100 is most likely not going to help.

I would be willing to bet that cally 91 sucks (performance wise) due to all the additives put in the gas to help it run cleaner. That being said someone in cally adding 100 is going to be much different then someone in Florida that normaly runs 93 adding 100