Can one use E85 petrol in std. ABY S2?

[S2central.net]

Let me try...

1. Fit an adustable FPR - 034 do one

2. Fit a fuel pressure guage

3. Fit a wideband O2 sensor and AFR guage

4. Hook up a relay for the fuel pump to make sure its getting closer to 14V instead of 12V - flows more fuel


By increasing fuel pressure you should be able to dial in more fuel - try adding small amounts of E85 at a time.
On the AFR guage you'll want to see approx 12:1 at WOT - adjust fuel pressure for that.
See how much E85 you can run to that level and keep baseline fuel pressure below 5bar is my recommendation.

Doin rough maths I'd say 5bar gets you ~20% more fuel and so you should be getting towards 50:50 mixes of E85 and petrol. Don't quote me on that - just a rough swag here on a Friday night watching U2 on tele !

For 100% E85 running you'll need approx 40% more fuel then on pure petrol - with a switchable chipset (hint hint - talk to me) you can get more fuel than by just tweaking fuel pressure alone - trouble here is that you don't want silly fuel pressure if you can avoid it - and you''d hit the limit on stock injectors pretty soon. So...

5. Fit larger fuel injectors - maybe 440cc or 550cc rated - dont think you'll need to go as extreme as 650cc on a K24 turbo - plus look how low the fuel pressure is when Espen runs on petrol with injectors that size.

[macspring]

Definitely not for me,

Thanks Paul though for the explanation.

Will leave the second one alone, and wait for the first one to come back. Maybe this year.

[S2central.net]

Your not still waiting on that to 'come back' are you ?

For E85 - you can reckon spending 300-400 quid just for enough instrumentation and control of fuel delivery before you even get into funky chips... That is going to be offputting for a lot of folk alright.
But 95RON is kak - I hate it... I can just about get by on 97RON, but even then I can feel the edge is off a bit.

[EspenW]

Doin rough maths I'd say 5bar gets you ~20% more fuel and so you should be getting towards 50:50 mixes of E85 and petrol. Don't quote me on that - just a rough swag here on a Friday night watching U2 on tele !

For 100% E85 running you'll need approx 40% more fuel then on pure petrol - with a switchable chipset (hint hint - talk to me) you can get more fuel than by just tweaking fuel pressure alone - trouble here is that you don't want silly fuel pressure if you can avoid it - and you''d hit the limit on stock injectors pretty soon. So...

5. Fit larger fuel injectors - maybe 440cc or 550cc rated - dont think you'll need to go as extreme as 650cc on a K24 turbo - plus look how low the fuel pressure is when Espen runs on petrol with injectors that size.

Going from 4bar to 5 bar fuel pressure nets an increase in flow of apprx 12% (square root of pressure increase).
My software is for stock RS2 injectors with a fairly big turbo, so I guess DC is cranked up quite a bit, thus the need for low pressure with 630cc injectors on petrol.