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So i know that in these cars premium is required but has anyone used regular and had no problems or does it absolutley need to run premium
 

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You could probably get away with 87oct for one fill after that a "check engine" light will come on. I've used 89oct on my Premium fuel only cars in the past with no issues but I did alternate every other filling.
 

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Premium fuel is required for a reason. Superchargers generate heat. This can easily cause lower octane fuels to combust inside the cylinder prior to the spark plug igniting. This is called "pre-ignition detonation," aka "knock" and the engine has sensors built in to detect when this happens. When the sensors are triggered, the computer pulls timing. This is called "knock retard" or KR for short. KR is very bad for an engine. It can cause all kinds of issues, including loss of power, and will eventually lead to pieces inside the engine breaking apart. Ask me how I know. The only ways to reduce KR are to decrease intake temperatures (intercooler for your supercharger, $$$), or to increase the octane rating of your fuel. Premium fuel has a higher octane content which will allow it to handle more heat/compression before combusting, reducing the amount of pre-ignition detonation your engine sees, and thus less KR

Do yourself a favor and run the high-test. If you DO decide to run 87 or 89 MAKE SURE you get a scan tool and scan for KR throughout the RPM range! A small amount or KR (2-3 degrees) is normal at wide open throttle, especially the higher in the RPM range you go, but 99% of the time it should be at 0!
 
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