High-octane gas power question
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High-octane gas power question This is regarding the 100-103 octane race gas available at some tracks and gas stations.....
I know that running higher octane allows less risk of detonation therefore allowing to run more timing, boost, or both resulting in more power.
My question is if a car is tuned at 91 octane and all things staying the same (same tune, no more boost, etc) will running race fuel add power because it burns more efficiently?
In Lahmens terms (spell?
) If a person dyno's at 400rwhp on pump gas, what would you think they would dyno on race fuel if all else stays the same 
Sorry, I had some beers over lunch and started thinking about this...
I know that running higher octane allows less risk of detonation therefore allowing to run more timing, boost, or both resulting in more power.
My question is if a car is tuned at 91 octane and all things staying the same (same tune, no more boost, etc) will running race fuel add power because it burns more efficiently?
In Lahmens terms (spell?
) If a person dyno's at 400rwhp on pump gas, what would you think they would dyno on race fuel if all else stays the same Sorry, I had some beers over lunch and started thinking about this...
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Originally Posted by kcshaner
This is regarding the 100-103 octane race gas available at some tracks and gas stations.....
I know that running higher octane allows less risk of detonation therefore allowing to run more timing, boost, or both resulting in more power.
My question is if a car is tuned at 91 octane and all things staying the same (same tune, no more boost, etc) will running race fuel add power because it burns more efficiently?
In Lahmens terms (spell? ) If a person dyno's at 400rwhp on pump gas, what would you think they would dyno on race fuel if all else stays the same
Sorry, I had some beers over lunch and started thinking about this...
I know that running higher octane allows less risk of detonation therefore allowing to run more timing, boost, or both resulting in more power.
My question is if a car is tuned at 91 octane and all things staying the same (same tune, no more boost, etc) will running race fuel add power because it burns more efficiently?
In Lahmens terms (spell?
) If a person dyno's at 400rwhp on pump gas, what would you think they would dyno on race fuel if all else stays the same Sorry, I had some beers over lunch and started thinking about this...
Well if you make 400rwhp with 91 octane, what power might you make with more timing and 104 octane is your question.
I'd say that you'd make 450rwhp at least, maybe more. Making 400rwhp with 91 might be with timing in the mid teens, whereas with 104 you might be able to run stock timing advance. Timing makes power.
I make 738rwhp with 110L and 23 degrees of timing at peak HP. To run 93 pump gas I might need to cut timing back to like 15 degrees, not that I have tried.
I'd say that you'd make 450rwhp at least, maybe more. Making 400rwhp with 91 might be with timing in the mid teens, whereas with 104 you might be able to run stock timing advance. Timing makes power.
I make 738rwhp with 110L and 23 degrees of timing at peak HP. To run 93 pump gas I might need to cut timing back to like 15 degrees, not that I have tried.
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From: WWW.SPEEDINC.COM
Though octane and burn rate are not really related, generally most race fuels will have a faster burn rate, as most race engines operate at a high rpm, which have less time for a complete burn.
Actual burn rate is effected by much more than just fuel type however. Engine type, combustion chamber design(shape, quench), a/f ratio and the homogeny of the a/f, temperature, etc,etc,etc.
I think if you run 93 octane on the street, and mix in some race fuel at the track, power level will be similar, but you will have an extra margin of safety.
Actual burn rate is effected by much more than just fuel type however. Engine type, combustion chamber design(shape, quench), a/f ratio and the homogeny of the a/f, temperature, etc,etc,etc.
I think if you run 93 octane on the street, and mix in some race fuel at the track, power level will be similar, but you will have an extra margin of safety.
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Though octane and burn rate are not really related, generally most race fuels will have a faster burn rate, as most race engines operate at a high rpm, which have less time for a complete burn.
But going back to the original question-
My question is if a car is tuned at 91 octane and all things staying the same (same tune, no more boost, etc) will running race fuel add power because it burns more efficiently?
In Lahmens terms (spell? ) If a person dyno's at 400rwhp on pump gas, what would you think they would dyno on race fuel if all else stays the same 
In Lahmens terms (spell?
) If a person dyno's at 400rwhp on pump gas, what would you think they would dyno on race fuel if all else stays the same So the answer is yes it is possible to gain power.There is more to the race fuels than just higher octanes.
But it is also possible to gain nothing. Just don't expect much gain without tuning changes.
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Verdad Gallardo But that gain might be due to the fact that the test car was still getting knock with pump gas.
Higher octane is going to reduce knock earlier in the combustion stroke which has been stated a number of times. Going from 15 to say 25 degrees of timing with a 9 psi blower is huge.
Higher octane is going to reduce knock earlier in the combustion stroke which has been stated a number of times. Going from 15 to say 25 degrees of timing with a 9 psi blower is huge.
