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Going all the way means going all the way, then you might as well run it on 102 if you could find any, or afgas and I think the new racing fuel is 98... Your original question was what type of fuel do you need to run on a high compression engine, and my answer was, it doesn't matter, if you sort it probably it'll run on any fuel...

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Ofcourse you will get more benefit if you run high octane fuel in a high compression engine. You can run more timing, less fuel and all sorts of stuff. You will make more power. I was just saying, on a well sorted engine with high compression, and I'm talking probably not higer than 11:1, high octane is not compulsory...

Nice info. But what i'm thinking is... Building an engine with race'ing writen all over it, you might aswell go all the way. a Proper stroker with flat tops and a fully done head and my old setups 300deg cam should go hard and maybe one will enjoy it a bit more if and when its driven. My comp was 11: 1...

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Not a chance. I 100% believe to get more power after flowing head,balance bottom end,carbs,etc you up the comp to get more power. I have seen and heard of alot of engines and came to a conclusion that comp can increase power, especially torque.
Some examples:
My friend here at work's nephew bought a factory 95 Nissan Sentra Works rally car build by Nissan motorsport.It has a SR20DE motor that has been worked with the following:
Full head job.
Rally spec cam.(Anything from 300 to 320 degrees)
Balance job (Revved to 8500 with rally team)
Throttle bodies.
And a comp of something like 13 : 1.
Apparently according to the factory it made 190 to 200Kw.Can't remember if it is flywheel or wheel Kw.
They are going to drop comp to 11 : 1 to increase reliability and decrease engine wear.
I know of a Sabre with head job, mild cam and it makes 150Kw.

Another example is Minnesh's 1200 in Durban. Has all the standard stuff done to the engine and a MASSIVE comp. I think also 13 : 1. It also gives 2litre guys a go and it is a 1400cc engine.
If you want, I can give you his number and then you can chat to him.Very helpful guy.

If I were you I would keep the comp down to use 95 pump fuel.Why? The damn fuel price is going to keep going up and race fuel is very expensive.
I would recommend 10,5 : 1. This is on the edge to be safe. For this I think you will have to check your pistons or skim the GX head to max which I would not recommend as they are very valuable.

So most of you guys dont believe in high compression ratio's with a high octane fuel to make up for power?

I ran my 11:1 road car engine for years on 96 with no issues. Cam timing does come into it too though (wilder cams can tolerate higher calculated compression ratio). I wouldn't be running much higher than this on pump gas though.

Modern engines are able to stand lower octane vs high compression due to electronic timing trickery.

I disagree with b210sleeper, and agree with 1200gxman on most, but not even at 11:1 do you really need high octane, the 20V blacktop 4AGE motors run 93 and/or 95 happily, and they are 11:1 standard.

Clive, I used to run my 4AGE that's turboed on 95 just to make sure, but sometimes they ran out and I used 93 and it made no difference, no pinging at all.

Octane can help prevent knock, but if you fuel your engine properly with the right timing settings, you don't need such a high octane number most of the times. Some engines are also less prone to knock than other, due to combustion chamber, piston and valve design, and with them you would be able to use far lower octane and run more timing than most others.

See one needs to know what is the increase in power with a higher compression ratio, say 12 : 1 or higher. And fueling.

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I don't agree. The GX engine is standard 10:1 and it uses normal 93 here in ZA.
My VW 1.8i engine is 10.5 : 1.Actually all VW engines are 10.5 : 1 and it runs fine on 93 and 95 octane.
I think it is from 11:1 that one must go 95 and higher octane to prevent detonation.
I know of a guy that build a performance A15.He used a GX head that was skimmed to the max. No detonation and I think he is running 95 octane.

over 8.5:1 would be higher than stock

again, if you aren't detonating you don't need higher octane.

10:1 engines start to need aviation gas, 12:1 for sure, but then it still what octane...

more octane doesn't magically make more power...