NSW Corvettes

Technical Tips => Pre 84 => Topic started by: rebel on April 03, 2003, 08:36:33 PM

Title: 100 Octane in a C3
Post by: rebel 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 .... ?

Title: 100 Octane in a C3
Post by: Adam 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

Title: 100 Octane in a C3
Post by: Scott81 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.

Title: 100 Octane in a C3
Post by: Adam 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...

Title: 100 Octane in a C3
Post by: rebel 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 ....

Title: 100 Octane in a C3
Post by: Brutus 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.