Recommended Gas?
#11
08-09-2009, 11:58 AM
#12
08-09-2009, 10:19 PM
i use 92 octane with 10% eth. ****ing hippies! lol i would use i know the bikes stock can do 80 whatever octane with 10% eth. but with mods and my PC3 i dont know what the downloaded tune is set for on octane so i just use 92 octane better safe then sorry. i think the 20 cents per gal. is worth it till i get a real tune.
#13
08-09-2009, 11:06 PM
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#14
08-10-2009, 02:09 AM
#16
08-10-2009, 07:33 AM
I am new to sport bikes but have been tuning my Talon engines for years. You want to use the lowest octane possible that doesn't knock. For cars at least that means go with the recommended from the manual or up to 2 points more.
If it's the same as computer controlled cars the optimum power scenario is chosing the octane that just keeps the engine from knocking (heard by a knock sensor not your ears)... if you go higher then that you will actually lose power.
Sure higher octane fuels are less prone to knock but what most people don't realize is that higher octane fuels actually burn slower.
In most modern cars the ECU watches the knock sensor for any activity. If all is well it advances the timing to the loaded map values tuned by the engineers. If, however, it starts seeing knock it starts dropping timing and you take a performance hit. So what you want is enough octane to avoid the ECU from retarding your timing.
So let's say that point is 89 octane that your car never sees knock. Now you go and put 94 octane in. It still won't knock... so the ECU will still be on the same map curve as the 89 octane. BUT now you have a slower burning mixture. What this does is it delays the peak pressure point of the burn.... thus reducing the actual timing. This will reduce your performance and mileage.
I just picked up my F4i a few weeks ago so I have no idea yet how it's system works but I assume the above probably applies is some manner.
If it's the same as computer controlled cars the optimum power scenario is chosing the octane that just keeps the engine from knocking (heard by a knock sensor not your ears)... if you go higher then that you will actually lose power.
Sure higher octane fuels are less prone to knock but what most people don't realize is that higher octane fuels actually burn slower.
In most modern cars the ECU watches the knock sensor for any activity. If all is well it advances the timing to the loaded map values tuned by the engineers. If, however, it starts seeing knock it starts dropping timing and you take a performance hit. So what you want is enough octane to avoid the ECU from retarding your timing.
So let's say that point is 89 octane that your car never sees knock. Now you go and put 94 octane in. It still won't knock... so the ECU will still be on the same map curve as the 89 octane. BUT now you have a slower burning mixture. What this does is it delays the peak pressure point of the burn.... thus reducing the actual timing. This will reduce your performance and mileage.
I just picked up my F4i a few weeks ago so I have no idea yet how it's system works but I assume the above probably applies is some manner.
Last edited by Jaxman; 08-10-2009 at 07:45 AM.
#17
08-10-2009, 08:41 AM
#20
03-27-2010, 02:15 PM
I am new to sport bikes but have been tuning my Talon engines for years. You want to use the lowest octane possible that doesn't knock. For cars at least that means go with the recommended from the manual or up to 2 points more.
If it's the same as computer controlled cars the optimum power scenario is chosing the octane that just keeps the engine from knocking (heard by a knock sensor not your ears)... if you go higher then that you will actually lose power.
Sure higher octane fuels are less prone to knock but what most people don't realize is that higher octane fuels actually burn slower.
In most modern cars the ECU watches the knock sensor for any activity. If all is well it advances the timing to the loaded map values tuned by the engineers. If, however, it starts seeing knock it starts dropping timing and you take a performance hit. So what you want is enough octane to avoid the ECU from retarding your timing.
So let's say that point is 89 octane that your car never sees knock. Now you go and put 94 octane in. It still won't knock... so the ECU will still be on the same map curve as the 89 octane. BUT now you have a slower burning mixture. What this does is it delays the peak pressure point of the burn.... thus reducing the actual timing. This will reduce your performance and mileage.
I just picked up my F4i a few weeks ago so I have no idea yet how it's system works but I assume the above probably applies is some manner.
If it's the same as computer controlled cars the optimum power scenario is chosing the octane that just keeps the engine from knocking (heard by a knock sensor not your ears)... if you go higher then that you will actually lose power.
Sure higher octane fuels are less prone to knock but what most people don't realize is that higher octane fuels actually burn slower.
In most modern cars the ECU watches the knock sensor for any activity. If all is well it advances the timing to the loaded map values tuned by the engineers. If, however, it starts seeing knock it starts dropping timing and you take a performance hit. So what you want is enough octane to avoid the ECU from retarding your timing.
So let's say that point is 89 octane that your car never sees knock. Now you go and put 94 octane in. It still won't knock... so the ECU will still be on the same map curve as the 89 octane. BUT now you have a slower burning mixture. What this does is it delays the peak pressure point of the burn.... thus reducing the actual timing. This will reduce your performance and mileage.
I just picked up my F4i a few weeks ago so I have no idea yet how it's system works but I assume the above probably applies is some manner.
f4i's will run better if not the same on unleaded as it would premium.
Most engines (including the F4i) do not require the use of high octane gasoline simply because they're not designed with high compression combustion chambers. A good rule of thumb is to utilize the lowest octane rating which doesn’t exhibit pinging. Along those lines, using a higher octane gasoline in an engine not designed to do so, will not improve performance, although most oil companies would like to make you believe that it does; high octane/more money