100 Octane fuel for $7.35 per gallon in a daily driver?
#16
05-19-2013, 07:16 AM
Ok..just did it. 5 gallons of 100 racing and 9 gallons of 91 octane -- to be honest,
I didn't notice much difference -perhaps the rest is crappy 76 gas station 91 octane and I have been filling up 91 v power from shell??? Perhaps i should've filled it all up with 100.......
Edit: came back home...reset my expectations ..drove off after few hours...and YES....there's a difference!!! It's very quick on its feet...in fact the sport felt like sport plus a few time!!!!! From now on I'm doing at least 6 gallons of 100 octane (18 gallons C4S tank)
.....it's worth it!!!
I didn't notice much difference -perhaps the rest is crappy 76 gas station 91 octane and I have been filling up 91 v power from shell??? Perhaps i should've filled it all up with 100.......
Edit: came back home...reset my expectations ..drove off after few hours...and YES....there's a difference!!! It's very quick on its feet...in fact the sport felt like sport plus a few time!!!!! From now on I'm doing at least 6 gallons of 100 octane (18 gallons C4S tank)
.....it's worth it!!!Warning: this is like eating Kobe Beef every day. You start doing it, now your car expects it and without it, your car will feel deprived
#18
05-19-2013, 10:54 AM
ChuckJ
#19
05-19-2013, 11:44 AM
I am thinking getting the gas up to 93 octane is important because both gas metering and spark timing are reduced with 91; thus power and mileage is reduced. I'm not sure if the add-on products will be recognized by the sensors, but it would be interesting to run a couple tanks of 91 and take a 0-100 timing; then run a couple tanks with the additive and take another 0-100 timing.
ChuckJ
ChuckJ
Hard acceleration will not highlight the difference between 91 and 93 or even 100 octane.
Under hard acceleration the DME goes open loop and richens the mixture and this richer mixture is less prone to detonation. Also, timing is generally retarded too because the richer mixture burns quicker, the flame front travels faster.
If you really want to note the difference between 91, 93 and 100 octane gasoline fill up the tank with 91, 93, then 100 and drive the car like a grandpa. In this style of driving the higher octane gasoline will permit more advanced timing and fuel economy and drivabilty with be better. You'll notice the drivability right off the bat. The fuel economy you'll have to monitor with the on-board computer.
Running say 91 vs. the recommended 93 will reduce fuel mileage and impact the drivabilty of the car.
One can note this if he spends any time in an area that sells 93 octane gasoline and fills up and runs a tank or two. The few times I've done this with my 03 Turbo the improvement from 91 to 93 is noticeable.
But back in the land of $4.279/gallon 91 octane gasoline one becomes accustomed to the performance/behavior and that's that.
It is certainly up to the owner if he feels strongly enough on the subject to go to the added trouble/cost of mixing 91 and 100 octane fuel to get 93 octane.
#20
05-19-2013, 01:48 PM
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I absolutely love Kobe beef ...so tender with a strong beef taste...yum!!
#21
05-19-2013, 01:49 PM
Registered User
Join Date: Jan 2012
Location: Silicon Valley, California
Posts: 2,293
Rep Power: 150 Fuel metering is independent of octane. Ignition timing can be cut back (retarded) if the knock sensors pick up signs (vibrations) of detonation.
Hard acceleration will not highlight the difference between 91 and 93 or even 100 octane.
Under hard acceleration the DME goes open loop and richens the mixture and this richer mixture is less prone to detonation. Also, timing is generally retarded too because the richer mixture burns quicker, the flame front travels faster.
If you really want to note the difference between 91, 93 and 100 octane gasoline fill up the tank with 91, 93, then 100 and drive the car like a grandpa. In this style of driving the higher octane gasoline will permit more advanced timing and fuel economy and drivabilty with be better. You'll notice the drivability right off the bat. The fuel economy you'll have to monitor with the on-board computer.
Running say 91 vs. the recommended 93 will reduce fuel mileage and impact the drivabilty of the car.
One can note this if he spends any time in an area that sells 93 octane gasoline and fills up and runs a tank or two. The few times I've done this with my 03 Turbo the improvement from 91 to 93 is noticeable.
But back in the land of $4.279/gallon 91 octane gasoline one becomes accustomed to the performance/behavior and that's that.
It is certainly up to the owner if he feels strongly enough on the subject to go to the added trouble/cost of mixing 91 and 100 octane fuel to get 93 octane.
Hard acceleration will not highlight the difference between 91 and 93 or even 100 octane.
Under hard acceleration the DME goes open loop and richens the mixture and this richer mixture is less prone to detonation. Also, timing is generally retarded too because the richer mixture burns quicker, the flame front travels faster.
If you really want to note the difference between 91, 93 and 100 octane gasoline fill up the tank with 91, 93, then 100 and drive the car like a grandpa. In this style of driving the higher octane gasoline will permit more advanced timing and fuel economy and drivabilty with be better. You'll notice the drivability right off the bat. The fuel economy you'll have to monitor with the on-board computer.
Running say 91 vs. the recommended 93 will reduce fuel mileage and impact the drivabilty of the car.
One can note this if he spends any time in an area that sells 93 octane gasoline and fills up and runs a tank or two. The few times I've done this with my 03 Turbo the improvement from 91 to 93 is noticeable.
But back in the land of $4.279/gallon 91 octane gasoline one becomes accustomed to the performance/behavior and that's that.
It is certainly up to the owner if he feels strongly enough on the subject to go to the added trouble/cost of mixing 91 and 100 octane fuel to get 93 octane.
How does every body feel about 76 vs chevron vs shell...I checked it out and 76 is on top tier list...!
#22
05-19-2013, 06:34 PM
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