E20 and stock tune
 

a circle track friend mixes up e20 95 octane per their strange rules and i wondered if the stock tune would be able to adjust to it and squeeze a couple more hp. i auto cross in stock class and cannot run a tune.

will lose a power if it not tuned

Your in Alabama USA ?


You have access to 93 usa AKI fuel ?? I assume this usually let stock tune run at full potential ie IAM =1 if so log your cars ecu if the IAM is at 1 then using higher octane fuel on the stock tune will have no effect.


If the fuel your running is resulting on an IAM (Ignition advance multiplier) less than 1 then running a better fuel will help.


The stock tune is rated to cope with 10% ethanol fuels, 20% will still be in the adjustment range for fueling. But it will take the ECU a considerable amount of time to adjust the fuelling, so just pouring E20 mix in at track then straight out on track is not a good idea.(unless you have flex fuel setup , even then a few km driving is recommended) you would want a 100km or so of varied driving to allow the ecu to learn fuel trims through out the rpm range, the upper rpm ranges take a while to learn unless you drive in a specific manner.


However if iam is already 1 then their will be no advantage on stock tune.


as previous guy said you would need to retune to take advantage of the higher octane rating and also adjust your fueling so you don't run high fuel trims due ethanol content.

yes Alabama USA, we have 93 e10 and i stay 1 or very very close. just curious if the higher octane and cooling of the ethanol would help in our 100 degree summers to bring power back like a cooler day. maybe not a power help but restorer? summer is when i drop below 1

if the iam is dropping below 1 then a higher octane fuel will usually help reduce knock and hence let the iam return to 1 for max ignition timing.


NA engines loose power on hot days or high altitude as air is less dense and theirs also compensation tables in ecu for ignition timing vs intake air temp and as intake temps climb ecu will reduce ignition timing to help reduce knock regardless of what fuel is in tank or if any knock is detected.

i spray my air temp sensor before each run with water to try and help that part. lol

@ryan t that sounds counterintuitive as you're only trying to trick your car into running on conditions that don't really exist...

Drag racers have iced the intake for years so i just spray mine. Im not the only one that does it where i autocross. Turbo cars soak their intercoolers

The iced intake and soaked intercooler help reduce intake temps. Spraying the sensor with water just makes it think it's running cooler when its not. Unless you meant the air filter, in which case I'd doubt it makes a worthwhile difference.

The stock tune can handle e20. I don't believe it will run any better. It will also take a while to adjust. I doubt it will run better than 93. Probably the same, after it adjusts.

This is incredibly ignorant.

2 Options:

Stock tune will already run max timing for stock header on 93/94. If adding more E% helps power above 7k in the hot weather then you decide to do that then you should run that mixture all the time which, is a pain in the ass.

A non-stock tune without any non-factory features is practically undetectable unless you have semi in-depth knowledge of the platform.

power is out until fuel tirm learned will