Chris,pull it back to 10.5,we've had nothing but grief in recent times with comps any higher than this given the nanny goat piss(see petrol)available these days.The 98 available from BP will give you the right bang for your buck,and forget octane booster(long term)too costly and next to worthless unless your throwing litres at it at a time....Avgas...hard to get,expensive,not available by pump unless your very friendly with your local airport authority and furthermore we are being weened off it at motor sport events more and more as the years go by.In time it will be banned for motor sport.
KISS 10.5 will be more than enough but i would DEFINATLY put it on a chassis dyno.
Research an operator by phone(may take a while)and if he's any good he will give you a basic jet/choke set up over the phone prior to taking it to his dyno once you explain what the engine measurements and goodies are.

chris why not put an a15 oval port head on there to drop compression a little, if you could get it to around 11.5 or so you would be ok.

if honduhs and celica's can runn 11 crs, dont see why you couldnt with good tuning. but when you gt it back to png avgas might be more available ;)

shame its not readily available any more in australia- unless your part of a small airport or some sporting applications.

basically you cant get it at the service stations

Forget E85 or any E/petrol blend -- ethanol makes less power than gasoline.

Go with the 110 Avgas, which is petrol (gasoline) and is good for 14:1 compression.

Probably the cheapest way to lower compression that Ive seen is by using these sparkplug
sleeves that screw onto the spark plug thread and place the plugs higher up in the tube.
Its kind of a pre-combustion chamber. I remember some old wheels magazines and later parts
trader mags advertising them in NSW - they where supposed to increase gas mileage.

If you can get them made by drilling some big bolts in the centre and taper the entry like
a funnel and on the opposite end a thread to place your sparkplug into then you are set.
You can calculate the amount of extra displacement by liquid measuring the amount of
fluid from a syringe that these sleeves take with the plugs screwed on.

Has anyone ever seen these things for sale in NSW or elsewhere via mail order from the old wheels magazines?

Its a type of glow plug similar to these smartplugs.

http://www.smartplugs.com/about.htm


You can always try singh lines :)
[url=http://www.gassavers.org/showthread.php?t=6465]http://www.gassavers.org/showthread.php?t=6465

Yeah okay that's fair enough.

It's the corrosive factor I am worried about. But I think things should be okay. I'd also like some info on how it burns and what rate it burns at, as I would expect the consumption to rise considerably.

And then the trick is to find someone who'll work with me?! The mechanic today wouldn't have a bar of me and he was pretty dead set on my ratio's being 'crazy' to start with.

I'll try get a hold of a decent fuel first and jet the thing at home. If I drag it to a rolling road with only some fine-tuning to do it shouldn't be such a major deal for the mechanic.

I have a document released for the V8 supercars teams explaining most stuff re E85. Its not a doco i would be comfortable posting but it generally says that nothing has to be changed except for larger injectors and checking pump supply. Tanks, fuel rails, and injectors shouldnt be affected. The V8`s run a much lower compression ratio than what you have and are only using it as a enviromental PR exercise. aAir/fuel ratio recomendations are also listed.

If I move to VIC will you Dyno my beast!??

EDIT: For free?.....I'll bring a carton of West End Draught [also affectionately nick-named 'swamp-piss']

Thanks a bunch Simon, great you stepped-in as I was about to PM you. Was racking my brain and decided I'd get in touch with you or Dave.

I'd like to hear Dave's opinion on the sustainability of the Ethanol mix fuels.

Would you happen to have any decent information on the fuel, any Data sheets at all? I'm searching the fricken' uni-database but all I get is environmental debates on it's worthiness as a enviro-fuel but nothing solid on it's chemical behaviour.

I am particularly interested in the corrosive risk of the fuel and it's combustive characteristics.

You will be fine with E85, Different retailers mix the ethonol with different unleadeds. Some use 91RON some 98 and some even use racing unleaded. But generally its around 104 RON.. but MON is a better indicator of detonation resistance. I`ll have to look up the MON.

Carb jetting will have to be changed for E85 too.

If you can`t run good fuel you will have to have it with sub optimal timing, you will make less power than if you dropped the comp ratio and run optimal timing. You will need a good tuner either way.


EDIT: I missed your last post about the lack of availability!
Lower the comp with dished pistons? or move to Vic!!!
mmmmmmm, not very helpful i know :(