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DISCUSSION => General Topics => Topic started by: ecalder on February 17, 2011, 07:58:36 AM

Title: Octane
Post by: ecalder on February 17, 2011, 07:58:36 AM

Hey fellas! I have a quick question...

I was just in Europe and was amazed that the lowest octane on gas there was 95 and it went up to 102. Here in Houston the best we get is 93 but at the race track we can buy 97 and 110. Out of curiosity, will it make a difference in my engine's performance if I use these higher octane gasolines? They're far more expensive than the 93 octane option, but if it would give me a little push I might consider them.

I'm running an m42 with the Mark-D 93 octane chip.

Thanks!

Title: Octane
Post by: colin86325 on February 17, 2011, 09:02:15 AM

They use a different octane measurement scale over in Europe, so the numbers appear higher for the same octane level.  In the US we use AKI, which is (RON+MON)/2

Title: Octane
Post by: ecalder on February 17, 2011, 10:10:04 AM

Got it! So I guess putting 97 octane (based on our calculation method) in my m42 at the track isn't going to do me much good...

THANKS.

Title: Octane
Post by: colin86325 on February 17, 2011, 10:21:36 AM

Ok, there are 2 issues here.  In Europe you observed higher octane numbers at the regular pump because these octane numbers are based on a different octance rating system.

In the US you can also buy special higher AKI octane gas at the race track. You wouldn't normally see these blends at regular gas stations. Putting the higher octane gas in your car at the track would offer additional protection from pinging if your car was already pinging.  You won't get any more power unless you have a special ECU chip that is mapped to use the higher octane.