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To be honest, I never really used flex fuel.

Seems good, in the real world once you're on E85 you don't need 98, as the availability is fine unless you're driving to Mildura etc.

That said, flex isn't very hard. All the ECU needs to know is ethanol % which it turns from 0V to 5V.

Then the ECU takes that input which may be like 2.5V, and applies a certain percentage of a correction map to fuel/timing/boost, relative to the voltage of that input.

That's all there is to it

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To be honest, I never really used flex fuel.

Seems good, in the real world once you're on E85 you don't need 98, as the availability is fine unless you're driving to Mildura etc.

That said, flex isn't very hard. All the ECU needs to know is ethanol % which it turns from 0V to 5V.

Then the ECU takes that input which may be like 2.5V, and applies a certain percentage of a correction map to fuel/timing/boost, relative to the voltage of that input.

That's all there is to it

i regularly drive to brissie.

Then I suggest you get a wideband and flex fuel

Wideband because playing with correction maps is likely going to be needed if you want it perfect. Its quite time intensive and expecting it to be PERFECT from a few hours on a dyno will never be feasible.

There's a lot of "hm, I'm idling at 13.7 AFR when I'd like it to be 14.7 when I am on 72% 98 and 28% E85" goings on

then again, can i justify paying 3k or so to make car flex fuel capable? 800$ for injectors, nistune, 1k +-, sensors and stuff, 1k, scotty intake 300?

i'll still run stock turbo.

Running E85 on stock turbo is really not a cost effective/convienient solution

Technically speaking, all E85 does is removes limitations of less than optimal systems, its not like you're gonna slam 30PSI into a stock turbo with a ton of timing for other explodey reasons...

If you could hit MBT and Peak compressor efficiency from your turbo on 98 without it pinging to death, switching to E85 wouldn't give you more power, I've been told that's why some people see big gains from E85 and some people don't

There's still gains to be made from advancing the timing and taking advantage of 107 octane.

Boost will also come on sooner.

But I think if you're spending that much on upgrades you should at the least get an $800 high flow and get another 60-70rwkw out of it while you're there, sacrifice a bit of response given the factory turbo is responsive and linear enough let alone with E85.

Technically speaking though, advancing timing only increases power to a point, after a point it starts reducing power.

If you're not pinging at that point, on 98 well, you don't need E85. It's possible in some lovely systems to not be pinging at MBT.

Same thing re: Boost pressure.

But in the real world, where we do stuff like add turbos to systems designed for lesser turbos, well, E85 starts becoming cool.

Would be curious to see what happens on a stock system, but you aren't gonna run more than 10psi on it anyway.

I would wager youd gain more powars per dollar by upgrading to a hiflow on 98, vs converting to E85 on a stock turbo.

Running E85 on stock turbo is really not a cost effective/convienient solution

Technically speaking, all E85 does is removes limitations of less than optimal systems, its not like you're gonna slam 30PSI into a stock turbo with a ton of timing for other explodey reasons...

If you could hit MBT and Peak compressor efficiency from your turbo on 98 without it pinging to death, switching to E85 wouldn't give you more power, I've been told that's why some people see big gains from E85 and some people don't

There's still gains to be made from advancing the timing and taking advantage of 107 octane.

Boost will also come on sooner.

But I think if you're spending that much on upgrades you should at the least get an $800 high flow and get another 60-70rwkw out of it while you're there, sacrifice a bit of response given the factory turbo is responsive and linear enough let alone with E85.

so. 4k? LOL.

I'm planning on moving to the country, so there will be winton days on 98 and any tracks in city E85

saves me having to do a run down to MELB with jerry cans to do a tampered day.

Planning on going north?

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