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New tune version 4.0 available!
- Thread starter danbfree
- Start date
For me, it has plenty of power to get around town.
87 is the recommended fuel for the Fiesta (according to the manual), but perhaps you know better than Ford?
I'm just trying to find ways to get around town more economically, while when needed, fuel up with 91 or 93 octane fuel.
However, since 90% of my driving is street use as a daily driver, I hope to save a penny with 87, and was just wondering if there was a tune for better mpg available.
I don't think the idea deserves the trolling comment.
87 is the recommended fuel for the Fiesta (according to the manual), but perhaps you know better than Ford?
I'm just trying to find ways to get around town more economically, while when needed, fuel up with 91 or 93 octane fuel.
However, since 90% of my driving is street use as a daily driver, I hope to save a penny with 87, and was just wondering if there was a tune for better mpg available.
I don't think the idea deserves the trolling comment.
OP
Thread Starter
#63
Thread Starter
#63
OK, I'll bite and assume you're OK getting even less power than Ford's already neutered factory tune and more carbon build up and just say that if you want fuel economy, reliability and, oh ya, the power that it's rated for, you simply run premium... also, just about all tunes are the same on the freeway anyway, the difference comes when you put your foot down. So if anything, even my high performance tune has helped freeway mileage a little by simply being more optimized and not needing to put my foot into as much... Sorry for being facetious, but this is all truth: Premium gets better mileage and cleaner engine, tunes actually help mileage by being more optimized and not requiring as much throttle for day to day driving too.
OP
Thread Starter
#64
Thread Starter
#64
NO, you need to read again and watch how you speak to people here who know what they are talking about. 93 IS the *recommended* fuel, 87 is the minimum acceptable to not damage the engine. It will not tun as lean or hot as optimal so you will get more carbon build up and poorer mileage. You bought the wrong car if you are unwilling to give it the gas it needs to perform right. Are you the guy that was trying to say the same "87 recommended" thing on FB and ignored me? so instead you just keep fishing for the answer that you'd prefer here?
I still have to see if I'll need one.
The temps haven't yet exceeded 85F on my daily commute. Even the 1.4 liter Cruze did well up to about 100F.
This car has a lower gear ratio, 200cc more, and the turbo kicking in 1000rpm later.
I don't think, even with heat soak, that i'll be lacking any power with 87 for commuting.
The majority of the time, I'm not racing it, just daily commuting.
The performance of the 1.6 liter is sufficient, up until where the boost takes over (then it's plenty).
The temps haven't yet exceeded 85F on my daily commute. Even the 1.4 liter Cruze did well up to about 100F.
This car has a lower gear ratio, 200cc more, and the turbo kicking in 1000rpm later.
I don't think, even with heat soak, that i'll be lacking any power with 87 for commuting.
The majority of the time, I'm not racing it, just daily commuting.
The performance of the 1.6 liter is sufficient, up until where the boost takes over (then it's plenty).
OP
Thread Starter
#71
Thread Starter
#71
Man, I still think you should just run premium, especially in any heat above 80 it will help with fuel economy by not being as easy to pre-ignite as well... What octane do you have available where you are? 87,89,91? But using premium you will get the low-end torque it should so you don't have to give it even more throttle, which obviously sucks more gas...
The engine has to detect knock to correct for it. A sudden detonation event may not be detected in time for the ecu to pull timing. With a stock tune and regular daily driving it would have to be very bad fuel or some serious hotspots to cause a destructive event. It’s still not a good practice to rely on the ecu to correct for the fuel. Running 91 or better is cheap insurance.
There will definitely be knock, the ECU pulling timing is in response to it hearing knock in the first place. While 87 octane can be ran on the OEM tune a 91 octane tune has a different/higher base of timing and boost etc...which would result in a much more aggressive occurrence of detonation when running 87 octane that would be unsafe.
Timing is pulled in a step like fashion when knock is detected, it will pull a certain amount of ignition timing and if knock is still occurring it will pull another increment of timing on and on. This means a large amount of knock could take several iterations of ignition timing decrements where knock is still happening.
Timing is pulled in a step like fashion when knock is detected, it will pull a certain amount of ignition timing and if knock is still occurring it will pull another increment of timing on and on. This means a large amount of knock could take several iterations of ignition timing decrements where knock is still happening.
OP
Thread Starter
#79
Thread Starter
#79
You're right, with all that trading back and forth of pro's and cons and the minor hassle of using two fuels every fillup you should just run 91, if that's your mid-grade... I wouldn't run anything lower for long-term use, with DI engines it can create carbon buildup even more easily on low octane.
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