100 octane unleaded??
11-06-02, 10:42 AM
#1
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100 octane unleaded??
A gas station in my area is selling 100 octane unleaded fuel. I have a SC 400 with a Weapon-R ECU upgrade. Can the ECU adjust to a higher octane or would I just be wasting my money??
11-07-02, 02:31 AM
#3
octane isn't a measure of 'richness,' it's a measure of the ability to resist preignition (knocking) so it will work in higher-compression engines. I'm no engineer so don't quote me, but it seems that the compression ratio is the deciding factor for octane rating although it is also affected by ignition timing - retard timing (and lose power) to prevent knock - would advancing timing past stock be an advantage? Ouch, stop, too many questions, my brain hurts -
11-07-02, 02:37 AM
#6
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10.5:1. BTW that 11:1 figure was just a blind shot in the dark 
. My point was that compression has to be significantly higher for the recommended octane to jump from 91 to 100.
. My point was that compression has to be significantly higher for the recommended octane to jump from 91 to 100.
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11-07-02, 02:53 AM
#8
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Nah, 100 octane is the opposite of rich, it's lean fuel. Fuel that ends up less combustable due to the retardant additives. That is the point because at high compression, the last thing you want is premature detonation.
11-07-02, 02:19 PM
#12
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High octane fuels...
High octane fuels are usually only needed if you are pinging or on high compression cars (or low compression with Forced induction, thus creating high compression 
) The fuel burns easier thus creating more power. If you put 100 octane in your engine, do a full tank and your car should be more rev-happy. Like a nice surge up to peak power. Jap spec Soarers are supposed to have 100 octane fuel, but the best I can get here in Australia from most gas stations is premium unleaded (98 octane). If I put normal fuel in (standard 93 octane unleaded) the car feels hella sluggish. With the 98 octane I the car feels extremely light, betraying the weight penalty that it should have.
Give it a shot and see how you like it. Higher octane wont damage your engine. Lower will. Reset the ECU at the same time.
Toan.
) The fuel burns easier thus creating more power. If you put 100 octane in your engine, do a full tank and your car should be more rev-happy. Like a nice surge up to peak power. Jap spec Soarers are supposed to have 100 octane fuel, but the best I can get here in Australia from most gas stations is premium unleaded (98 octane). If I put normal fuel in (standard 93 octane unleaded) the car feels hella sluggish. With the 98 octane I the car feels extremely light, betraying the weight penalty that it should have. Give it a shot and see how you like it. Higher octane wont damage your engine. Lower will. Reset the ECU at the same time.
Toan.
11-07-02, 06:06 PM
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I tried dropping a e-mail to Weapon-R a couple weeks ago. I did not get a reply. Im going to fill up on the way home from work tonight. I will let you guys know the results.
11-08-02, 12:20 AM
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Dude isn't it going to cost over $80 to fill your car with a 100-octane gas?
Theres a 76 gas-station in Pasadena, CA, that sells the 100-octane racing fuel and they're like $4.75/Gallon.
Theres a 76 gas-station in Pasadena, CA, that sells the 100-octane racing fuel and they're like $4.75/Gallon.