The reason they can go so high on the comp ratio is because of direct injection.

The fuel is injected into the combustion chamber very late in the compression stroke. This helps prevent detonation.

Us poor folk that have to put up with port injection need to use good fuel as a detonation counter measure.

My turbo A12 has a BMEP of 285 using E85.

Would love to dyno it now but......the engine is all over my work bench :P
And no I haven't herd about that Mazda ....14:1 on pump that's :o ok I may have to do more research

Yes, go alittle farther. Dyno it now, then after you convert it to alcohol, dyno it again. Let us know how much the HP drops. It shouldn't be very much.

Have you heard the new Mazda will have 14:1 compression? It has 12:1 this year. And runs on petrol.

Sory for the late update .....the motor: 1mm oversized pistons,double valve springs,re-ground cam,head port, triple cut valves and raised compression ratio ....I also already have kiehin fcr quad carbs,e15 dizzy and extractors...
So should I go a little further with the a12 ? And run methanol or maby e85 ?

L14 is rare over there? here, i only saw 1 L14 in my mate's PB210.

and a couple of rumored 510 with L14 motor, but never see them with my eyes.

L series or LZ18ET, no pollution gear, L20 crank in L16 block
machined mains for 82mm stroke with L14 rods from malaysia
w/ 1.5mm shaved Z20E slugs = 1.9L combo 2cm shorter block height.

One would assume that if you are going to the trouble of running E85 or methanol that you are actually doing something to the engine, in which case you can easily double your power.

Generalising a little but an engine will make the same power no matter what fuel you run it on. All a different fuel means is that you can run a more aggressive state of tune, which is where the power increase actually comes from.

You need compression (or boost if you're talking turbos), timing, cams & revs to get the best out of advanced fuels.

NB: you need 200-300% of the fuel system for methanol, but only about 30% more fuel E85.

E85 won't make any more HP than gasoline, so the A12 can handle it no problem -- if you upgrade the fuel system as previously described for alcohol. The A12 block, crank, rods & pistons are already strong enough for alcohol.

E85 is a better option by far, but again you are limited by the inherent issues of the A series - being the strength of the standard components, and the lack of capacity (particularly with an A12).

You are better going A14/A15 or L-series if you want bang for buck, but even then you will get belted by even the most basic turbo efi car.

To take full advantage of running an alcohol fuel you have to make significant changes to the engine so it can accommodate that fuel.

If you are pursuing more power and you are open to other engine conversions then it's a pretty bizarre question, the answer is obvious.

If you are pursuing more power and want to stick with the A-series then go find more cubic inches.

Other wise tell us what your budget is, what else you want to do with the A12 and the question would be much easier to answer. You haven't even mentioned any other upgrades and to be honest an A12 running on methanol would be absolutely shyte unless you go for a significant upgrade in induction, compression and cam (money, money money).

Bang for buck = more cubes.