alextaylor29

I read somewhere, that putting in a few gallons of 109, (if you start with 91, the highest here in AZ), blends to a 95-96 range with based on my mods will give me about 10% more HP/TQ.

So per my mods below I'm officially at ~550 HP/625TQ @ the wheels!

Seriously though, I do this once a month on a Friday so I can enjoy the extra power over the weekend.

It's a nice, "Instant mod," that costs comparatively little and does translate to the bottom line as far has addition HP.

My headers just sing when I'm booting it! Too bad it's still hot in AZ right now, 100 degrees at the moment, but still!

Definitely try this at least once if you've never put in a higher octane gas in your ride.

Alex

AWOL

hit the dyno

alextaylor29

My right foot is my dyno.

POWERRRRRRRRR!

AMGPilot

The "10%" won't occur instantly the ecu needs to learn the higher octane but seeing lower knock sensor activity.

to figure new octane number you need to do the following maths

(Gallons * Octane A) + (Gallons * Octane B)
---------------------------------------------------
total gallons

so for 95.5 octane you'd need 6 gallons of 109 and 18 gallons of 91

urbamworm

This is to funny and couldn't have come at a better time. An arguement taking place today in my thread was with the other side telling me that race gas won't make any difference unless you change your tune for it. Which you are confirming isn't true by stating your car is faster by just adding in a few gallons

There is a reason people mix in or run race gas, because it helps!

RedBullJnky

Nice! We have 93 octane down here and down the road from my house, at a gas station by the track, they have 100 and 110. Most people hit it before the track.

alextaylor29

I have a stage 3 Jerry Tune now so that might help a bit, but I don't have a 109 Octane tune I can, "Turn on."

It definitely helps though, you can absolutely feel it. It does take a few minutes/hours for the car to, "Wake-up" adjust the timing, but it's definitely faster. Many people know more about this than I do, so just wanted to share this fun bit of info in case you were interested.

I remember reading in Motor Trend a few months back where they put in a few gallons of 109 in a Bentley Continental GT the were testing (which has 500 HP stock) and they dynod it and it showed a 10% HP gain, so 550 HP just on the gas.

I mean if you think about it, additonal octane, epecially from 91 to 109 will make more HP even if the car is not perfectly tuned for it.

I can absolutely feel the difference in my car, no question about it!

In fact in WWII, our planes beat the german planes as we ran 100 Octane in ours vis 87-90 in theirs.

Fuel is rated according to its level of octane. High amounts of octane allow a powerful piston engine to burn its fuel efficiently, a quality called "anti-knock" because the engine does not misfire, or "knock." At that time, high-octane aviation gas was only a small percentage of the overall petroleum refined in the United States. Most gas had no more than an 87 octane rating. Doolittle pushed hard for the development of 100-octane fuel (commonly called Aviation Gasoline or AvGas) and convinced Shell to begin manufacturing it, to stockpile the chemicals necessary to make more, and to modify its refineries to make mass production of high-octane fuel possible. As a result, when the United States entered the war in late 1941, it had plenty of high-quality fuel for its engines, and its aircraft engines performed better than similarly sized engines in the German Luftwaffe's airplanes. Engine designers were also encouraged by the existence of high-performance fuels to develop even higher-performance engines for aircraft.

AMG_RL

They got us back by inventing airmatic.

RedBullJnky

03'55AMG

Lmfao^^^

Jakpro1

That's insane. Wonder who would take that side? Proven since these things came out that they respond to race gas nicely.

Yacht Master

FWIW
There is a VP station on Andrews a few bolcks south of Power line up here in Lauderdale. What kind of fuel are they selling in Pembroke Pines?

SterlingE55

Had to chuckle at this one.

RedBullJnky

I'll go tomorrow and let you know what the name of the gas station is. I believe it is inbetween Stirling and Griffen on 27. County line and 27 is the track.

citylightva

and putting E18 caliper bolts in impossible to reach locations...they've been getting us back for a long time

infantry

Interesting, I'm in AZ too. I want to run 100 octane but really haven't found a station at the pump. Another thing is isn't 109 octane leaded? Are you catless if it is leaded?

I remember back in my hometown of modesto, ca I put more than half a tank of 100 octane, cost me over $80 but it was honestly worth it. It didn't feel like it just made more horsepower, but I felt the car was able to use all of its potential horsepower, i.e. not pulling timing due to signs of detonation and all that.

It felt like the car was making the power it was suppose to make. I've done this maybe 8 times when I lived there, doing it once every few weeks. And every single damn time, it felt a bit quicker up top.

urbamworm

VP MS109 is unleaded. I assume since he said 109 octane that is what he used.

alltrac

Its sunoco...its high octane but,.its leaded. No good for cats or O2 sensor. Also they wont let you pump it in ur car. U must bring a gas can.

mrweelr

I always fill my ride with Union 76 Cool Blue 100 octane before I do hit the drags. Don't want to be running 91 monkey **** when trying to make my best passes. Can also add 5 gallons of Xylene for the same effect, but it's toxic and messy to deal with. Wish we had better fuel in California.

Quadcammer

My god folks, this is common sense.

1. If the car is seeing knock sensor activity on 93, you need a new tune.
2. If the car is not seeing knock sensor activity on 93, 95, 97, 109 or 402 octane fuel is not going to make any more power.

Higher octane without a tune for it (i.e. more timing) is useless.

GT-ER

What is bold is true...but 99% of all E55's will see SOME knock activity unless it is dyno tuned or EXTREMELY conservative and even then it tends to happen. Even 100% bone stock E55's have knock retard.

In this case, adding higher octane fuel WILL make more power due to the knock activity going away and it should be near instant ( maybe 2-5 minutes into it as the fuel system will take a while to exchange the old fuel with the new one ).

However, if you car is one of those cars with no knock retard due to your tune being conservative...it will not make more power. I've done the test before on my Ex-GTI 1.8T. If your engine makes a perfect combustion on 93oct fuel, 109oct will not make the combustion any better/powerful.

I think a lot of people don't realize WHY their cars make more power on race gas. It's not because the fuel it's self makes a more powerful combustion or because the ECU will advance timing all by it's self when it "sees" the race gas. It because most vehicles have SOME kind of knock retardation and when you put race gas that retardation will generally go away.

For example, your car at any given moment may see 18* of timing advance but the knock control is removing 2* due to knock activity at that moment so you end up with 16* total timing. With race gas, you'd get the whole 18*.

But this is not guaranteed, because if my car sees ZERO degrees of knock retard, then the car will continue to put out the same 18* regardless of octane ( 93 or above ).

Now, if your car is SWITCHING to a low octane map because of knock retard, then you will feel a HUGE difference after a while of driving with the race gas when it switches back to the high octane map...but this should not happen as your vehicle should be operating 100% of the time in the high octane map...if not then it needs a tune badly.

cal1

So you are at WOT heading down the track, IATs rising, running 93 on a 93 tune and timing is as far advanced as possible. Wouldn't a little 100 race gas (unleaded) help insure no knocking if nothing else?

GT-ER

Depends, if the ECU starts to pull timing due to IAT's and not due to knock activity then no...the race gas will not help. If the ECU pulls timing due to knock activity then YES, the race gas WILL help.

urbamworm

This is not true. A car can not be tuned for optimal ignition timing for every weather therefore a vehicle with any kind of ignition advance will always have some sort of timing correction from either higher intake air temps on a warmer day or from inaudible knock picked up by knock sensors. That is completely normal even on a stock vehicle and is the reason the engine management system has the ability to adjust for over 10*.


It is quite logical to think about. If a car is tuned to show optimal ignition advance in 70 degree weather then the same car when running in 80 degree weather while experiencing less dense air and higher intake air temps will adjust for it and pull timing accordingly or on the flip side in cold weather will have all it's parameters met to allow for full advance and have zero correction.

The properties of race gas help to aid in retaining power based on what it does for the engine.

cal1

Thanks for the explanation.

I read your post on the other thread going on about race fuel. That is reason enough for me to continue to run a few gallons of race fuel for track days. I still see it as knock insurance if nothing else. Oh, and it smells good.