93 Octane in a 997S
#31
The fact is, ANY octane higher than that which is necessary to prevent the engine from knocking does nothing to improve performance. Octane's only purpose is to increase the pressure level at which point the fuel will combust. It has absolutely NO benefit to performance. If your car does not have pre-ignition using 91 octane fuel, using a fuel of a higher octane will be of no benefit. In the USA, the EPA dictates that ALL fuels have the same level of detergents, so claims that running a higher octane fuel will keep your engine cleaner is also a myth.
Last edited by 1999Porsche911; 09-08-2006 at 10:50 PM.
#32
Originally Posted by 1999Porsche911
If your car does not have pre-ignition using 91 octane fuel, using a fuel of a higher octane will be of no benefit.
#33
Originally Posted by Crod
So are you saying that advancing the timing does not create ANY added power ?
#34
I often mix 1/4 100 and 3/4 91 to produce 93. I notice a difference. The engine does not have the same initial hesitation as with 91 (very small difference). I think it is more important to buy "top tier" gas than 93 vs 91. Shell and Chevron are top tier fuels.
#35
Originally Posted by gdctus997
I often mix 1/4 100 and 3/4 91 to produce 93. I notice a difference. The engine does not have the same initial hesitation as with 91 (very small difference). I think it is more important to buy "top tier" gas than 93 vs 91. Shell and Chevron are top tier fuels.
#36
Originally Posted by PorscheC4
I noticed someone said something about octane booster. does that stuff actually work?
#37
Originally Posted by 1999Porsche911
No. I ment exactly what I said. If you modify your timing to be more advanced than stock, then assuming everything remains constant, you might need a higher octane fuel if knock is present. However, the increase in octane does not improve performance...advancing the timing (within limits) might.
#38
Porsche recommends 93 for my GT3. At the track I mix 91 & 100 50/50 to get roughly 96 octane. There's a noticeable difference between that and plain 91. I've also run straight 100 and it's no better than my 96 blend, hence it's just pissing money away. So, the sweet spot for my car is somewhere between the 93 that the factory suggests and my 96 mix.
#39
Originally Posted by Holger B
Porsche recommends 93 for my GT3. At the track I mix 91 & 100 50/50 to get roughly 96 octane. There's a noticeable difference between that and plain 91. I've also run straight 100 and it's no better than my 96 blend, hence it's just pissing money away. So, the sweet spot for my car is somewhere between the 93 that the factory suggests and my 96 mix.
#40
I don't know if there's any advantage to using >93 with the stock set up. I'm sure there are tuners that sell programs to take advantage of higher octane, but I wouldn't go there since I like my warranty, trust Porsche's engineering, etc.
The only testing I've done is with my butt at the track. It's clear that the car pulls stronger with the higher octane. How much I have no idea, but it's real & noticeable. There's no difference that I can tell between 91/100 and straight 100, so >91/100 is wasting money IMO.
The only testing I've done is with my butt at the track. It's clear that the car pulls stronger with the higher octane. How much I have no idea, but it's real & noticeable. There's no difference that I can tell between 91/100 and straight 100, so >91/100 is wasting money IMO.
#41
#42
Originally Posted by wross996TT
I guess I will pass on this....
#45
I wise old man once told me "Replying to threads that are 3.5 years old is a waste of your time and the others who read them thinking it's a new thread."