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Old 01-17-2013, 06:54 AM
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F-BIRD'88 F-BIRD'88 is offline
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I don't think any of us are willing to risk good money on a "what-if" of this kind. This was originally a question posed by Vinnie and I chimed in to put my 2 cents worth in. I've never tried the combination and never will. Advancements in the sport are not made by those who sit back and are comfortable with the status quo, they are made by those who buck the system and try different things. Again, like I said though, I'm not foolish enough to try this, it was just an exercise in fantasy land.

Tech: This is exactly what I am getting at. You are promoting something you have never tried in any fashion to see if it is even remotely practical. Yet you are promoting this and yourself as if you are an authority.

You are not an authority on this and now admit that you would never even think about trying it.

I have built and run high compression ratio engines (been to the dark side) and even stepped over the edge.

Your over simplified incorrect DCR theory and calculations based on incorrect real valve timing

Totally ignores other factors like the HEAT OF COMPRESSION. Look up your gas laws.
The real in cylinder presssure and temperature in the rngine as it is reunning at speed.
The ever increasing number of fireing cycles per sec as the rpm rises. MORE HEAT with less TIME TO REMOVE THE HEAT @ WOT. AS RPM RISES. ALl thisand more effects the octane requirement-compression ratio.

High compression ratio engiens that actually run and make power @WOT need a higher octane fuel.
On the street once you get beyond about 10.5:1 things get real dice. on even good premimum 92 octane gas.
EVen worse if/when the fuel octane is not so good.
Even worse if hwne the tune os not 100% correct in all cylinders. Even worse on a hot day or after running for extended time on the hyway, then suddendy ge4t on the throttle from a stop. when things are hot.
You learn this actual real world experience. many people have had to learn the hard way thru $$engine failure$$$, th real practical limits of pump gas fuel and compression ratio, reguardless of the cam timing.

Stop trying to mis repressent yourself as a authority on this and stop representling this as a absolute.

Don;t you think that if this workedwe whould have figured out a long time ago and ther would be no higher octane fuel
Or all engines would just be over cammed to get them to run on pump gas ????????
Start ny checking your history. All the research on all ths HAS BEEN DONE..
All the modern combustion shapes ( fastburn, cloverleaf),,, etc etc ARE NOT NEW.
They are old designs that were done a long time ago.

The best most effective way to avoid detonation is to back off the spark advance.
And that is exactly what modern computer controled engines do to avoid damage when ever
you rug the gas petal and operating conditons are NOT optimum.

Stop promoting this recklessly, when you freely admit you never intend to try it....etc...

Like I said Build your first high performance engine and get back to us.....