Knock Sensor

[Guest ante]

Fair dinkum! the kiwi bloke is still right, even without the forplay.

[Mals BA XR6T]

OK, let's make sure I have this right.

Higher Octane fuel in our XR6T's will produce more power because of it's inherent abilities, not by the amount you will be able to advance the ignition timing.

Oh and for "ante", Thank You XR6TK1W1 for your comments :D

[Guest Mr Walker]

  Mals BA XR6T said:

OK, let's make sure I have this right.

Higher Octane fuel in our XR6T's will produce more power because of it's inherent abilities, not by the amount you will be able to advance the ignition timing.

Unfortunately this does not appear to be correct. If the 'maximum' advance has been reached then any additional octane will not be offset by additional advance therefore no extra power.

Ford Power you are correct in saying that :

"it does not necessarily contain more energy than say 98 octane fuel"

but your other statements aren't necessarily correct:

"102 octane fuel will give more power as it gives more even combustion within the cylinder, and thus results in better engine dynamics. The increase on power is a result of the fuel being used, NOT the ECU advancing the timing."

Higher octane fuels are slower burning and this can be detrimental to performance unless you have a high enough compression ratio to suit OR your timing is advanced enough. Methanol for example is slower burning than 98 Octane so people using it have very high compression (14+:1) and very advanced timing to make use of it's benefits.

If you can't wind up the boost, increase compression or advance the timing any futher then 102 octane fuels aren't beneficial.

[Mals BA XR6T]

So now I'm right , , :D , , :lol:

[Guest Mr Walker]

No, you're not.

[Mals BA XR6T]

:(

[Turbo6man]

Mr Walker> You got in before me with that perfect explanation of why higher octane does NOT necessarily equate to higher power - It is clear that some people don't understand the basics of how their engine works - this is fine and I'll never knock anyone who is attempting to learn - you will learn by listening to the explanations given by those who do know. The big Q is how do YOU know who THEY are ???

There is a very good website I've seen mentioned in the threads called something like "how things work" - do a search for it and I'm sure you'll get some basic info there to help you understand the relationship between compression, timing, and fuel octane.