Author Topic: 100 Octane in a C3  (Read 10198 times)

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Offline rebel

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100 Octane in a C3
« on: April 03, 2003, 08:36:33 PM »
This is more a question for Brutus as he is our resident fuel expert but open to any one with an opinion ....

I can understand 100 octane (or more) making a difference in a newer car where the computer can compensate and adjust as necessary. But in a carbbie car like any C3, is there any leverage to be gained by higher octane fuel or is it merely to stop pinging .... ?

Offline Adam

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100 Octane in a C3
« Reply #1 on: April 04, 2003, 08:38:41 PM »
It wont do any more in a new car than an old car. The diff is, u have to adjust the old one manualy. Either way, if they run high compression they need it, if they dont then they dont.

On a side note, heres somthing u should know about our beloved Optimax. The main diff in this particular 98 fuel is it is high density, which really means u get more fuel per unit and it will last longer IF its leaned out. On a computer equipped car, it compensates by leaning out the fuel mixture automaticly. But with carbies, it will run rich unless u lean it out. Likewise if your already adjusted to Optimax and run any other fuel, u will be lean.

Adam
1980 LG4 stock 305 running LPG.


I'm a highway staaaaaarrrr...

Offline Scott81

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100 Octane in a C3
« Reply #2 on: April 08, 2003, 05:44:18 AM »
rebel,

As stated, on a normal engine it is probably a waste of good $$$.  In my motor which is 10.5:1 compression I add 5 gallons of 110 octane to each tank of premium.  From what I was told, the higher octane has a smoother burn to it and also helps cool the motor where the regular gas will have more of an explosion to it....if that makes sense.  I did notice a big difference once I started burning the better gas, then again my motor was built to burn it.  It's not cheap even here, $4.00 a gallon(CAM-2) for a 5 gallon bottle, then it costs another $30 to fill the tank.  VP Racing Fuel is almost $30 for 5 gallons in the C-12 type 108 octane.
When I start my car I want my neighbors to think the end of the world is coming.  - Homer Simpson

Offline Adam

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100 Octane in a C3
« Reply #3 on: April 08, 2003, 08:46:58 PM »
The more octane, the more "resistance" it has to ignite (to a point). In other words it wont pre ignite (b4 the spark) in a high compression engine and stuff your valves, thats the main thing the octane is for.

But again it all needs to be balanced, if u can make a fuel with 500 octane, doesnt mean your engine will be super powerful.

Metho can make your octane number soar...
1980 LG4 stock 305 running LPG.


I'm a highway staaaaaarrrr...

Offline rebel

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100 Octane in a C3
« Reply #4 on: April 08, 2003, 10:33:37 PM »
hmmm, I wonder what'll happen if I pour some of Kentucky's finest bourbon in there ....

Offline Brutus

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100 Octane in a C3
« Reply #5 on: April 10, 2003, 07:05:00 PM »
Higher octane fuel alone will not increase your engine's horse power. I can ask them at the lab for a more technical explanation, but suffice to say if you don't have the mods that require higher octane then it will give you no real benefit.
BOB

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