I am welding up fuel tanks for the toy - quite a cathartic job if you enjoy endless tig welding but I find myself forced to make a decision I have been putting on the too difficult pile....

My engine(s) are ex Indy Car units that were designed to run on methanol. Because of that the compression ratio is about 15:1. I have a few sets of reduced compression pistons but to run petrol the injectors - complicated things with separate swirl plates - would need to go. Not the end of the world but not ideal.

I had thought of using methanol but there are a few issues - not least the fact that I understand it rots aluminium fairly quickly. I really can't justify bag tanks and stainless steel is just too nasty and difficult.

I have seen some race fuels that might just tolerate the compression ratio - but still need to change the injectors.

I then thought about E85 (Ethanol blend). I know very little about this but understand:

(1) that the flow rate is much higher (like methanol)

(2) It does not corrode aluminium

(3) some fuel pumps will spit the dummy a bit earlier but others are fine

(4) It can cope with high compression ratios.

Has anybody got any experience of this? What are the chances of keeping the original injectors, aluminium tanks and the whole thing not exploding in an expensive pile of bits if I use E85?

Might be worth asking this on Uphillracers.com ?

Some of the lads on there use 'mixtures' when going up the hills

Good idea - many thanks