Adding E85 To Premium 98 As An Octane Booster

[limpus]

So I pulled into my usual servo on the way to work to fill up on 100ron e10 fuel today and discovered that its been phased out across the state...i've been running it for over a year and the car has been tuned for it...with E85 popping up at Caltex servos all over the plan is to eventually make the switch over but I can't do that yet due to an inadequate fuel system...650cc injectors on a 3L 2JZ with a GT30...

So now I'm thinking if it would be possible to add a couple of litres of E85 to a tank of 98 just to get it close to what I used to run and what the car has been tuned for...I've got a few events coming up in the next month and can't get the car tuned on e85 in time...and running normal 98 premium isn't really a good idea too...what do you guys think?

[paulr33]

sounds risky

does your ECU have a hand controller style feature

ie can you adjust the tune without going to a tuner?

[limpus]

Running a AP Engineering PFC...so i can back timing off if i need to...but i'll need to do it every time i start the car...

But surely a few litres of E85 into a tank of Premium 98 wouldn't hurt right?

[scotty nm35]

Shouldn't be a problem, run 15% e70 to make up the 10%?

Why dont you get some new injectors though, they are getting cheap. Are yours 14mm oring top and bottom? I just fitted ID1000 to mine, cost me $700 with plugs. The group buy on here has them even cheaper, $550 I think. Mine idles perfectly on Eflex.

[Harey]

When Caltex E85 is in use then add 6L of E85 for every 44L of 98 to give you E10.

Or if Caltex is using E70 then add 7L of E70 for every 43L of 98.

Was E10, 90% 98 fuel and 10% ethanol or 90% 91 fuel and 10% ethanol?

[limpus]

Well...the plan is to get larger injectors to make the full switch to E85...but like i said in the interim i would still like the small margin of safety the e10 100ron fuel gave me while i do the events over the next month...

[R31Nismoid]

650cc should be more than enough for a GT30 on E85

On PULP the highest I’ve seen is 65% with 700cc injectors making 365rwkw (2.65l) so far.

So add in a nice big 30% for E85 use @ the same power and there is room. If you wanted a bit more a 2-3psi increase in rail pressure would fix that. You’ll struggle to make 360-370rwkw on a GT30 anyway so I don’t see where the 650s are a problem…

I think fuel mixing whilst estimated with some level of accuracy, is not 100% fool proof and a bit of a risk.

[limpus]

Thanks Ash. Well I was hoping to maybe try to run e85 with the current 650s but at the moment its not possible to get it tuned before Deca this weekend and a few other events i have have in the coming weeks...

[DVS JEZ]

For now just trim the timing down everytime u start it so u dont mess with afr's.

[KiwiRS4T]

60L of E10 contains 6L of ethanol

7L of E85 contains 5.95L ethanol

You don't have to be too exact.