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Old 08-05-2011, 11:35 PM
bigx5er bigx5er is offline
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Quote:
Originally Posted by Couper93 View Post
Not sure what the other posters are trying to say so if I repeat, my bad...
Octane is the temperature at which fuel will ignite. Higher the octane, higher the temp to ignite, hence more compression, hence more power. Our engines run a higher compression so in order to optimize performance you need a high octane fuel. Yes modern engines have knock sensors so when you do have bad gas or lower octane, you won't damage the engine but with that , lower octane can result in less timing to compensate for less compression which will lead to less performance.
Complete agree, well said. My original response was more around cost savings and MPG. So far I have noticed a performance difference with 89 octane. The X5 is plenty fast, so it's not a big deal for me. I'm still working on measuring gas mileage to see if it is worth it. As someone else said, if MPG drops 5% then it's a push and I should just run premium
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