112 octane tuning question.
112 octane tuning question. I want to run 112 octane at the track, but run 93 octane on regular days. Can this be done if I don't jump on it when I am running 93? This is a 85% track car
Staging Lane
Joined: Aug 2018
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if 93 doesnt contain ethanol i think you can get away with at,
93 stoich is 14.63 and 112 is 15 so about 3% leaner but if it has ethanol it would be 14.1 which is 7% leaner,
either way you would need to run closed loop, i think some ecu add more fuel on power enrichment with high long fuel trim,
you would need to setup your low octane table for 93 and high octane for 112 and adjust the bias learning table to use 112 most of the time,
im not sure if this would work the main issue is if you are on track and the ecu uses the low octane table and you lose alot of power or when you fill 93 and it uses high octane table and it knocks and maybe your knock sensor is desensitized and doesnt hear the knock you could damage your engine,
its gonna be eaiser if you have hptuner with you and switch tunes everytime you change fuel,
or just use race e85 with flexfuel sensor would save you lot of trouble
93 stoich is 14.63 and 112 is 15 so about 3% leaner but if it has ethanol it would be 14.1 which is 7% leaner,
either way you would need to run closed loop, i think some ecu add more fuel on power enrichment with high long fuel trim,
you would need to setup your low octane table for 93 and high octane for 112 and adjust the bias learning table to use 112 most of the time,
im not sure if this would work the main issue is if you are on track and the ecu uses the low octane table and you lose alot of power or when you fill 93 and it uses high octane table and it knocks and maybe your knock sensor is desensitized and doesnt hear the knock you could damage your engine,
its gonna be eaiser if you have hptuner with you and switch tunes everytime you change fuel,
or just use race e85 with flexfuel sensor would save you lot of trouble
You would be totally wasting your money on 112. You will see no benefit, other than the weight reduction from your wallet.
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From: PDX-OR-USA
Race 93 or 104 until your closing in on 14:1...
If you go pump 92/3(which will have some ethanol) ,, and switch to race 93 or 104 at the track, your close enough to be safer, saving a ton of money and not having to dink around is worth something to me... YMMV You can also help by running your rev limiter lower on the street, especially if its a add-on that has a dial or a pill..
I worked a bit with Sunoco and got to talk to a lot of chemists that do fuel, they all agreed that mixing street gas is bad enough, mixing race fuels is a crap shoot ,, you have to know the exact chemical mix to make sure they are additive and not subtracting octane. the additive packages change dynamically on almost every fuel run depending on the chemical packages cost , its sold like crude oil ,, the various Oxygenation chemicals that is. Mixing race and street fuel is even worse..
If you go pump 92/3(which will have some ethanol) ,, and switch to race 93 or 104 at the track, your close enough to be safer, saving a ton of money and not having to dink around is worth something to me... YMMV You can also help by running your rev limiter lower on the street, especially if its a add-on that has a dial or a pill..
I worked a bit with Sunoco and got to talk to a lot of chemists that do fuel, they all agreed that mixing street gas is bad enough, mixing race fuels is a crap shoot ,, you have to know the exact chemical mix to make sure they are additive and not subtracting octane. the additive packages change dynamically on almost every fuel run depending on the chemical packages cost , its sold like crude oil ,, the various Oxygenation chemicals that is. Mixing race and street fuel is even worse..
Instead of trying to mix fuels which will be very inconsistent unless our going to drain your tank and mix and re-fill with the new mix it will be much safer to pull the correct amount of timing which on a 50 shot wont be very much. Your factory O2 sensors will not like leaded race gas either.
TECH Junkie
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From: White Bear, Mn
Let's back up a few steps here first. First of all do you know if your setup is octane limited? In other words does your car make more power with more timing that 93 octane can't support?
Get the **** out of here with your logic and reason. Seriously, though, a disturbing number of people have no idea as to the true answers to the questions you just posed. They just assume more timing equals more power when it may not be the case. They follow that assumption to the idea that more octane rating plus more timing equals superhero power, when it may actually have no benefit.
Get the **** out of here with your logic and reason. Seriously, though, a disturbing number of people have no idea as to the true answers to the questions you just posed. They just assume more timing equals more power when it may not be the case. They follow that assumption to the idea that more octane rating plus more timing equals superhero power, when it may actually have no benefit.
You are right. I don't know if I am octane limited. I just want to run a 100 shot at the track without taking it to my tuner and have him retard the timing for the NO2. I figured that adding 112 octane wouldn't hurt with an N/A run and would allow me to also run a 100 shot with no problems. That is what I am asking?