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Discussion Starter #1
Iv'e heard this before octane without a flash is useless. I did 1/2 & 1/2 93 & 112 it screamed. The acceleration was intense it would hit a buck 50 quick. I know I'm probably going to hear all kinds of guff on this but it is what it is.
 

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Iv'e heard this before octane without a flash is useless. I did 1/2 & 1/2 93 & 112 it screamed. The acceleration was intense it would hit a buck 50 quick. I know I'm probably going to hear all kinds of guff on this but it is what it is.
I've heard the same speculation as well. Some say you'd only see a difference in power if you have a turbo or non naturally aspirated engine if you use race fuel. I too wanted to try this out but couldn't reason the expensive price per gallon if I knew it might not give any return.
 

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Careful, 112 is usually leaded.

The highest unleaded I've seen is 105.

You might ruin your cats and o2 sensors and I don't know what else.
 

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Discussion Starter #4
They had up to nitro methane as far as what you wanted. And I went with the 112 and I mixred it 1/2 and 1/2. It was worth the $ and I'd do it again hey man what do you got to lose but a few $. It works flash or no falsh as far as my rideby the time I got back tp the frwy it was smoking God what a rush.
 

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Caymaniac
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Your engine timing will only adjust to a certain point with your stock ECU. Past a certain octane level, your car in incapable of developing the compression to benefit from the increase in octane beyond something below 100 (the way we calculate octane in the US).

On a side note, I know a guy who damaged his valves when he was forced to run 91 octane in his Porsche that was running a 100 octane map. Predetonation. Lower octane fuel can't withstand the pressure/temperature the tuning allowed the car to develop. Bad news. Aside form the lead, you will only hurt your wallet going higher than your car can run.

I did 50/50 100/91 at the track (unleaded) and I absolutely could tell that the car pulled harder. No question. Was it worth the $7.50 a gallon? Nope. Not for me. But I have four kids. LOL.
 

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Your exhaust and tail pipe(s) will love the extra octane.
 

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Dave N007 nailed it. Using more octane then your engine requires will not result in more HP and may actually develope less power. My old race car had a 14:1 compression ratio. It needed octane.
 

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Discussion Starter #9
I've got the Sport Progerm from the factory and allthough Porsche makes no claims to any HP gains it is a differant story when it is engaged. You set the cruise and disengage the Spoert button and the cruies control has to reset itself. There is a definant differance while running it. Supposedly it only gives you a crisper ride but I have found that not to be the case. There is a defient power increase noticeable upon accelleration when I have it on as to having it off. I tried to do a couple of flashes and was told there was not enough room for all the info. Whether it is true or not I like it and the fuel was unleaded. Not something to do a lot don't want to clog the cats. But every once in a while it is worth it. I spoke with Klauss at the ruff store in Dallas and he stated the sport system is a tune in itself and no wonder the others failed. I could however send my ECU out but warraty purposes kills that idea. I think I got a car with the 10% extra hp from the factory. I'ts enough for me and I still slam my bdddy in his 911 non turbo everytime we race. So for now I am more than satisfied with the way it performs with what mads I have on it to date. But I do agree done to much could cause some serious problems so I would not recomend everbody going out and doing it.
 

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Where in Dallas did you find 112 octane?


They had up to nitro methane as far as what you wanted. And I went with the 112 and I mixred it 1/2 and 1/2. It was worth the $ and I'd do it again hey man what do you got to lose but a few $. It works flash or no falsh as far as my rideby the time I got back tp the frwy it was smoking God what a rush.
 

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It was worth the $ and I'd do it again hey man what do you got to lose but a few $.
When I replaced the cats on my 02 996 they were about $1800 each. In my book that's a bit on the pricey side for a bit of rush. However, have fun ;)
 

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Discussion Starter #13
Actualy it was in Pasadena TX I live in the bay area. And it would take a while to clog your cat's but they would eventually depending on how much you ran it could be as little as a month. They sell unleaded racing fuel as well but were out at the time. The brand was Sunoco and came from Oklahoma. You can buy online from them in 5 gallon or 55 gallon drums. It isn't that cheap but it it not as exspensive as you may think. I paid $10 a gallon and that is within cents of buying from them even with shipping. I belong to a Nissan Forum for my Frontier and a lot of the offroaders use it in rockclimbing and whatever else they do in theyre monster trucks. A couple of months ago the price was around $5.00 to $7.50
 

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Post some more pics of you car. It is wicked looking. I love it. :cheers:

Bay Area in Texas...I just learned something new.;)
 

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Discussion Starter #16 (Edited)
DaveN007 PM me and I will send you some of both as well a some of my old cars. Used to do some R&D with Honda for the S2000. They gave me one to drive and we went through 2 for max modification and a bit of racing I have a pic of the 1st one in the showroom with all the sponsors as well as my 66 Shelby AC427 signed by the dude at a Hooters event.
 

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What brand fuel is it?

I've searched and can't find any unleaded over 105 octane.
Highest non-leaded is 104 (that I've found). As others said, the stock ECU can only increase the timing to much on its own to match the higher octane. I have a dedicated race file on my RS370 software to take advantage of such gas. Also, be careful that you're reading the anti-knock number and not just the research octane number. The anti-knock number is the one that is of importance. To get that number you take the motor octane number + the research octane number and divide by 2. Places like VP Fuels will sell their product giving the research octane figures. Their 109 unleaded is really 104. ;)
 

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105 is what is says on their site.
Motorsport 109
• Motor Octane 101
• Research Octane: 109
• R+M/2: 105
Maybe they bumped it up a notch from when I last did my research. When I was comparing all the available race fuels to buy a large quantity (for my buddy's race shop) I looked at all the offerings. Either way...they still make is sound like its 109...when in reality its not.
 

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I would love to have a $1.00 for everytime I have seen this arguement that higher octane fuel nets more power. The only gain from higher octane fuel is the suppression of detonation/preignition.

In the high-dollar blended fuels people are buying, they also contain oxygenates and other additives that are giving the added throttle response but in total horsepower a dyno would reveal the truth. On a factory delivered/tuned car, using the lowest possible octane fuel without achieving detonation/preignition will net the highest horsepower possible.

An 87 octane fuel will burn earlier, faster and with a more complete burn than a 93 octane at a lower cylinder pressure. This means... if you are taking a road trip, on the highway and deem in unnecessary to floor it WOT, you will see a considerable GAIN in fuel economy. The reason for this is because the 87 compared to the 93 is making higher BTUs, thus more energy for the same throttle settings. Try it... you will start saving money immediately!

My 6psi Supercharged Yamaha is tuned for best performance with 87 octane. My Subaru will make 500AWHP on 93 Pump gas. Adding race fuel to the same engine without adding advance timing for the slower burn is a waste of money and can potentially harm internal engine components due to "wetting" of the cylinders due to unburnt fuel, added deposits on the valves and combustion chambers. Simple "Switch Tunes" typically give very little actual timing upgrades to warrant 93 octane let alone 105+ rated fuels.

If you don't believe it... hire a dyno for an hour, show up on empty with 87 octane fuel and make a few pulls. Then pour in 5 gallons of 93 octane and watch the power in most cases drop. All factory cars are delivered with a substantial "Buffer" in tuning to take in account for the median owner. The tuning range allows for the Prom Queen whose daddy bought her a Porsche for Graduation to the racer in most of us here who beat our cars on a track. Our shop in Alpharetta, Ga tunes cars everyday to the owner's driving style and needs. In most cases we deliver 8-10% power gains with an increase in drivability.

Take the challenge... try it. Don't fear the 87, embrace it. All cars are equipped with cylinder balance/misfire and knock sensors to care for your engine, so do not worry... it is not going to be hurt. Besides, most fuels are blended with ethanol which is a 130 octane rated fuel. If you really want to step up a tune... get your ecu tuned for e85 which is a 135 octane fuel. Our shop Supra is running as a daily driver, making over 1100rwhp on race gas and 800 rwhp daily on e85.

Here is a video of this monster! Some assembly required. Don't try this at home. Shop Website: http://www.topspeedsales.com

 
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