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I don't get the octane booster thing. Octane is a fuels resistance to the air/fuel mixture igniting from compression before the spark. Therefore higher octane allows you to run more advanced timing. If you're not adjusting your timing for the track why do you need octane booster? Upping the octane rating doesn't mean more power without adjustments.

Or am I missing something? Placebo effect?
Well our stock or slightly enhanced ECUs will allow a little more power gen before pulling back ... per the tuning experts up to 95 octane
I have been doing long term logging under 91 ... if and when I drop in a tank of 95 (at a nearby fancy station) the timing data will be revealing as to what our ECUs really do
 

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Well our stock or slightly enhanced ECUs will allow a little more power gen before pulling back ... per the tuning experts up to 95 octane
I have been doing long term logging under 91 ... if and when I drop in a tank of 95 (at a nearby fancy station) the timing data will be revealing as to what our ECUs really do
I'd be interested to see the results.

I should add, I'm no expert. From time to time I import cars from Japan where 100 octane is available at most filling stations. They require retuning to suit standard UK fuel.
 

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I'd be interested to see the results.

I should add, I'm no expert. From time to time I import cars from Japan where 100 octane is available at most filling stations. They require retuning to suit standard UK fuel.
Retuning?! Darn those are the higher power engines (100oct).
Figured the antiknock sensors would do their thing for lower octane fuel instead of needing that retune?
 

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No, it's the same as the uk. US 91 is like UK/Japan 95. US 93 is like our 98
Wait ... you noted REtuning of JDM premium 100 (RON) octane class motors ... though you also note the UK and JP octane "units" are the same ... and "standard" UK fuel surely still has the regular 95 and super 98 grades.
So detuning just to accommodate -2 RON points? Thats interesting ...
 

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so has anyone did a e85 tune to their vehicle? CLA 45 amg here. I see there are a mixture of cla owners here. Im not sure what my injectors are rated for, but I did purchase the AMS HPFP directly from them. Assuming if these are available for the car as an upgrade that means the injectors are big enough and lines are sufficient enough to withstand e85? Does anyone have any information on this, thanks.
 

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I have been running on an e85 mix for the past 4 months. All that is needed is a custom tune with the calibrated HPFP on the car and your good to go. I am currently running 40% ethanol on my cla45.
 

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E85 is compatible with the cars only if stated on your gas cap door, so pretty much the sport models, from what I've found. Mine is a 2016 sport and says 91 or E85 as minimum octane.

Next, E85 yes will give better HP and performance only if your car is tuned for it. Dumping race fuel or octane booster in your tank won't just instantly give your car 20+ HP without tuning the ECU to not compensate the higher octane.
My car is 208whp stock on 91 AND E85.
 
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