[enrita]

Originally Posted by BMWsky

I don't think it hurts anything, but it probably doesn't do much (if anything) to improve performance. It might help to keep things looking better on the aggressive maps.

i would run a small CM5 or CM3 nozzle with 50/50% water / alc instead. at least you have IAT in check and perfect timings constantly.

[Lulz_M3]

Originally Posted by benzy89

COBB currently doesn't have an upgraded turbo map does it?? I know that right now on v3 Maps there's Stage 1, Stage 1+, Stage 2 + Stage 2+. The same with the v4 Maps, but they're still in the Beta stage.

Also, I'm assuming it wouldn't be wise to run 100 oct. on a non-race gas map (where are these if they're available?).

You will actually lose power running higher octane unless you have the means to run more aggressive timing, but it wont hurt anything. I sometimes add a gallon or two to a full tank of 93 when it starts getting hot outside or if i plan on running the car hard. My car tends to be happy until it gets really heat soaked, the additional octane really helps the consistency of the performance.

[enrita]

Originally Posted by Lulz_M3

You will actually lose power running higher octane unless you have the means to run more aggressive timing, but it wont hurt anything. I sometimes add a gallon or two to a full tank of 93 when it starts getting hot outside or if i plan on running the car hard. My car tends to be happy until it gets really heat soaked, the additional octane really helps the consistency of the performance.

the more octane the better. you wont gain much power but you definetely wont loose it.

[Lulz_M3]

Originally Posted by enrita

the more octane the better. you wont gain much power but you definetely wont loose it.

Actually, you will lose power. Higher octane burns slower, more aggressive timing is a MUST to not only keep from losing power, but also to make more power.

[nafoo]

Originally Posted by Lulz_M3

Actually, you will lose power. Higher octane burns slower, more aggressive timing is a MUST to not only keep from losing power, but also to make more power.

Really? One time at the track, I put about 3 gallons of 109 in my tank with less than 1/8 93 left. I only got one run in at the track because some idiot on a bike blew his engine and leaked fluids all over the track.

However, on my way home I ran with a friend's friend's C5 Z06 and pulled him consistently 60-110ish.

My car definitely felt a lot smoother with the race gas, but maybe it was all mental? =p

[benzy89]

Originally Posted by Lulz_M3

You will actually lose power running higher octane

Was gonna say, I might not know where to get the Stage 3 Maps, but I'm sure as shit that the better octane you put in your car, the more power that it's going to deliver. And running Race Gas is going to be like running 93 + Meth anyhow, so you'd see a pretty good jump.

Reason I brought this up is b/c the COBB tune doesn't have Meth maps like its plug-in rivals, so I wasn't sure if there was a OTS Race Gas Map available.

[Pseudo Nim]

n00b question: is throwing race gas in the tank equivalent/better/worse than putting 93 + some sort of an octane booster?

[Carl Morris]

Only if your ECU adds more timing or boost than it otherwise would. Lulz_M3 is right if all other conditions are exactly equal and there is no detonation, higher octane is slower.

But our job, of course, is to make sure all other conditions are not exactly equal so that we can take advantage of the additional octane. In some cases the ECU will do that for you if timing or boost was previously being pulled.

[benzy89]

Originally Posted by Pseudo Nim

n00b question: is throwing race gas in the tank equivalent/better/worse than putting 93 + some sort of an octane booster?

Significantly, but 99% of people can't afford to run 100 oct (~$8.50 a gallon) unless it's for a special occasion. Octane booster has a diminishing return as you increase your base fuel. Basically, the 60 point (+6 Octane Pts) booster will have a bigger impact on 91 then it will on 93.

Better off just 2-3 gallons of race gas (on a low tank so it isn't diluted by 93 pump gas)instead of paying $15-20 for the octane booster.

[Pseudo Nim]

Originally Posted by benzy89

Significantly, but 99% of people can't afford to run 100 oct (~$8.50 a gallon) unless it's for a special occasion. Octane booster has a diminishing return as you increase your base fuel. Basically, the 60 point (+6 Octane Pts) booster will have a bigger impact on 91 then it will on 93.

Better off just 2-3 gallons of race gas (on a low tank so it isn't diluted by 93 pump gas)instead of paying $15-20 for the octane booster.

Understood. this is for the occasional track day more so than daily driving, of course. but filling up on race gas is murder at $7/gal... is there a "recommended dosage", assuming 93 otherwise?

[Lulz_M3]

Originally Posted by benzy89

Was gonna say, I might not know where to get the Stage 3 Maps, but I'm sure as shit that the better octane you put in your car, the more power that it's going to deliver. And running Race Gas is going to be like running 93 + Meth anyhow, so you'd see a pretty good jump.

Reason I brought this up is b/c the COBB tune doesn't have Meth maps like its plug-in rivals, so I wasn't sure if there was a OTS Race Gas Map available.

Octane does NOT = Power. The reason that Cobb must release meth maps is because in order to take advantage of the additional octane, the timing must be raised. Search for results from people running meth/H20 on Cobb off the shelf maps, they typically lose power and at best, gain no power at all.

In order to reap the advantages of additional octane, custom tuning must be done.

Race gas + pump gas tune + pump gas boost = pump gas numbers
Race gas + race gas tune + higher boost =

[benzy89]

Originally Posted by Pseudo Nim

Understood. this is for the occasional track day more so than daily driving, of course. but filling up on race gas is murder at $7/gal... is there a "recommended dosage", assuming 93 otherwise?

Personally, I'd bite the bullet and buy Race Gas for the occasionally track day. Here's why:

• It really doesn't change that much. Tossing 60 point octane booster into a tank full of 93, you'll only get it up to 95.5-96 octane.
• From an economic stand point, you'll lose more money using octane booster than if you just bought race gas from the start. Octane booster cost ~$20 a bottle & you can only use it on a full tank of gas (~$55 for a full tank of 93). So instead of costing you just $20, it actually cost about $80 in JUST GAS for a track day.

Bottom line is, when you take into account the performance & cost, you're best option is buying race gas. Just go buy an 8 gal jug of race fuel (~$50-60) & keep it in your garage for your track days. On days you have a track event, run your tank to near-empty & pour in just what you need for that day.

[benzy89]

Originally Posted by Lulz_M3

Octane does NOT = Power. The reason that Cobb must release meth maps is because in order to take advantage of the additional octane, the timing must be raised. Search for results from people running meth/H20 on Cobb off the shelf maps, they typically lose power and at best, gain no power at all.

In order to reap the advantages of additional octane, custom tuning must be done.

Race gas + pump gas tune + pump gas boost = pump gas numbers
Race gas + race gas tune + higher boost =

^^See last page when I asked if COBB has Upgraded Turbo/Race Gas Maps.

[Lulz_M3]

Originally Posted by Pseudo Nim

Understood. this is for the occasional track day more so than daily driving, of course. but filling up on race gas is murder at $7/gal... is there a "recommended dosage", assuming 93 otherwise?

A long read but a good one for those looking into octane boosters. Quoted from another website. My advice to you would be to add a splash of unleaded race gas to 93 on track days, unless you have a race gas tune to take advantage of it.

*begin quote*

Octane boosters offer little help in the quest for higher octane. Most popular street-legal octane boosters claim increases in octane ratings up to five points, and those boosters intended for off-road use only claim up to seven points. That's a lot of octane to hope for simply by pouring an additive in a tank. Sunoco told us that before they launched their GT-100 Unleaded retail pilot program, they wanted to be sure that a 100 (R+M) / 2 octane street legal fuel would be of value, and that enthusiasts would not be able to get the same (or better) results using an octane booster. Nine of the most popular retail octane boosters were put through a series of tests to determine where the consumer could get the most bang for the buck. The test results were verified by an independent testing facility, using several brands of regular unleaded and premium gasolines, just to make sure everything was legit.

According to Mark Borosky, Vehicle Test Engineer for Sunoco,"Of the nine octane boosters tested, none showed a significant increase, and one actually lowered the octane number of the test gasolines."Testing repeatedly showed a maximum increase in octane of 3.5 points by only two of the six street legal octane boosters when the recommended treatment rate was blended with lower base 87 octane gasoline. The best the remaining four products could muster was less than a one point increase. "While clearly no one would actually use an octane booster in a low base octane fuel, we wanted to give the manufacturers the benefit of the doubt relative to their claims of five-to-seven point increases," explained Borosky.

When tests were performed using 93 and 94 octane fuel, even the two best products from the previous tests produced a disappointing 1.5 to 2 point maximum increase. The remaining four street-legal octane boosters showed less than a .5 point increase. Those products designated for offroad use only didn't fare any better than the street-legal products. Subsequent tests where the dosage of octane booster was doubled, tripled, and even quadrupled produced only minimal improvements in octane, regardless of the base octane number of the test gas. In fact, quadrupling the treatment rate of the most powerful additive produced only a 3.5 point increase in octane when added to 93 premium, resulting in a cost of $3.25 a gallon.

An alternative path to octane euphoria is to blend gasolines of different octane levels yourself. It's easier than you may think, safe, and the results are predictable. The formula for mixing gasolines of the same type is pretty straightforward. When you mix a 50/50 blend of two unleaded fuels, simply average the two octane ratings to determine what's in the tank If you mix 94 and 100, you get 97. The same generally holds true for leaded gasolines, assuming the lead content is
nearly equal.

Blending a leaded fuel with unleaded, however, pushes the octane up a bit more than the math would suggest, due to the effect of the lead. Just a gram or two of lead blended into the unleaded fuel will raise the octane number significantly. Commercial leaded racing fuels contain anywhere from a trace to six grams of lead per gallon. If you were to mix 50 percent 110 octane leaded fuel with 100 octane unleaded, you would actually end up with an octane number around 106 to 107. Keep in mind that even the smallest amount of lead or leaded gas line with unleaded, could spell the end of your catalytic converter or oxygen sensor. The same holds true for using octane boosters intended for off-road use only. A word to the wise, check for any lead content in all the additives you might mix with your unleaded gasoline. And check with your state emissions regulations for street use.

We asked Sunoco's Wurth about using aviation fuel in an automobile engine. He was emphatic when he said, "Don't do it. Even though Sunoco is a major producer of aviation fuel, this fuel is specifically blended for aircraft engines. Aircraft operate under very different conditions than automobiles, and the fuel requirements are quite different as well. Aircraft engines generally.... run within a very narrow rpm range. There's no need for transient throttle response in an airplane because after the pilot does the initial engine run-up, the throttle is set in one position and the rpm doesn't normally change until landing. Also, airplanes fly where the air is cold and thin, and the atmospheric pressure is low. These are not even close to the conditions your street machine will see on the ground. Also, since most piston-driven aircraft cruise at 3,000 rpm or so, the burn rate of aviation gas is much too slow for any high performance automotive applications."

What is it that makes race gas so different? What's it made of? Sunoco tells us their GT PLUS 104 octane unleaded race gas is only 15-20 percent traditional gasoline, and about 85 percent additives! Actually there are about 120 different chemicals in GT PLUS. One reason it isn't street legal is the high oxygen content. The EPA requires that the oxygen content of a street legal fuel cannot exceed 2.9 percent. GT PLUS is about 3.5 percent oxygen. This fuel is light in weight at only 6.14 lbs-per-gallon. The high oxygen content improves the octane, and when the induction system is properly calibrated, this fuel will help make additional horsepower. The high oxygen content has a supercharging effect, since 3.5 percent oxygen is the equivalent to about 17 percent more air. Different fuels can actually alter horsepower 5-to-10 percent or more.

We wanted to to know more about the different types of race gas Sunoco had, and didn't realize there were five different types of racing fuel alone.

GT-100 Unleaded, is a clear fuel with a pump octane of 100, and will handle compression ratios of up to 12:1, and is street legal in all 50 states.

GT PLUS, is also unleaded, and is rated at 104 octane. It is suitable for compression ratios up to 14:1 and is colored light blue. It will not harm oxygen sensors or knock sensors in computer controlled engines. It is not street legal.

STANDARD, is a leaded fuel rated at 110 octane, is colored purple, and is intended for drag racing, road racing, and race boats.

SUPREME, is also a leaded fuel and is dark blue. It was developed to help resist vapor lock and meet the demands of sportsman, modifieds, offshore powerboats, and endurance racing where engines regularly run in excess of 7000 rpm.

MAXIMAL, we mentioned earlier, is colored red, has 116 octane, and is leaded. It is intended for exceptionally high performance applications like Pro Stock where extremely high cylinder pressures are common. Its extremely fast burn rate is satisfactory where rpm exceeds 10,000.

*end quote*

[igell]

What are the recommended oil change intervals when running Cobb tuning. Standard stg1 CA map?

[BMWsky]

Originally Posted by igell

What are the recommended oil change intervals when running Cobb tuning. Standard stg1 CA map?

That's pretty subjective. Personally, I change mine every 5000 miles or so.

[AWD Addict]

Originally Posted by benzy89

Significantly, but 99% of people can't afford to run 100 oct (~$8.50 a gallon) unless it's for a special occasion. Octane booster has a diminishing return as you increase your base fuel. Basically, the 60 point (+6 Octane Pts) booster will have a bigger impact on 91 then it will on 93.

Better off just 2-3 gallons of race gas (on a low tank so it isn't diluted by 93 pump gas)instead of paying $15-20 for the octane booster.

Typically, a "plus 6 point" label means +0.6, not plus 6 octane ROM/2 figures. If it were to give you that, it'd have to assume the size of your tank in order to give you the ratio. So a booster with "+ 6 points" is only going to bring your 93 to 93.6 ROM.

The best and most cost effective way to raise your octane is with toluene or xylene, which can be obtained at any paint or hardware supply store. These are dangerous chemicals, so they should be handled with care and caution.

Xylene is about 117 ROM octane level. So mixing with 91 octane from the pump in the following percentages will yield the following (approximate) results:

10%...........94 Octane
20%...........97 Octane
30%...........99 Octane

So 3 gallons of xylene on a 15 gallon tank of 91 will produce 97 octane (ROM). Many people who run their own "brews" will add a couple ounces of transmission fluid or marvel mystery oil as a lubricant to help protect rubber components in the fuel system, as toluene and xylene in high quantities can eventually dry them out.

[AU335i]

Originally Posted by Lulz_M3

I've been running a beta map from Cobb for S2+ Agg that fixed my boost oscillation issue. The fix is coming soon guys.

Good to hear!

Originally Posted by Lulz_M3

Actually, you will lose power. Higher octane burns slower, more aggressive timing is a MUST to not only keep from losing power, but also to make more power.

Originally Posted by benzy89

Significantly, but 99% of people can't afford to run 100 oct (~$8.50 a gallon) unless it's for a special occasion. Octane booster has a diminishing return as you increase your base fuel. Basically, the 60 point (+6 Octane Pts) booster will have a bigger impact on 91 then it will on 93.

Better off just 2-3 gallons of race gas (on a low tank so it isn't diluted by 93 pump gas)instead of paying $15-20 for the octane booster.

I agree with Lulz M3 on this one... not too long ago I threw in some C16 race fuel with some gas I thought was bad to see if it would help clear some timing issues up... it cleared them up but my car definitely felt ALOT slower...

although there are some variables to consider...because while the race gas mix was in my car boost logs showed the race gas made my car boost a good bit lower for some reason... car boosted fine afterwards with normal gas. and also the C16 was leaded... I only mixed a half gallon of C16 + 3/4 tank of 93... so I don't think the lead content was enough to do much damage but I think it might have played a role in why my car felt alot more "laggy" than with normal gas.


I actually just threw some octane booster (bought some ricey looking "NOS" 60 point octane booster last week) and for only $13 for a bottle I definitely liked using it for special occasions alot more than mixing the C16. Car feels great and boosts normal with clean timing logs.

[benzy89]

Originally Posted by AWD Addict

Typically, a "plus 6 point" label means +0.6, not plus 6 octane ROM/2 figures. If it were to give you that, it'd have to assume the size of your tank in order to give you the ratio. So a booster with "+ 6 points" is only going to bring your 93 to 93.6 ROM.

That's why I said 60 point booster... And I am not putting shit I can't pronounce into my gas tank

Originally Posted by AU335i

I agree with Lulz M3 on this one

And if you agree w/ Lulz, you'd agree that octane booster isn't worth shit

[AU335i]

Originally Posted by BMWsky

That's pretty subjective. Personally, I change mine every 5000 miles or so.

+1... I change every 5000 miles as well.

[E90SoFlo]

waiting for meth maps.....

[benzy89]

Originally Posted by AU335i

+1... I change every 5000 miles as well.

+1, stick to OEM fluids