92 octane in 3.8 supercharged?
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The pinging from regular fuel could do serious internal damage to the engine. Use regular only in an emergency, definitely not as a regular diet.
If you want to ruin your pistons fast; that would be the way to do it. I'm hoping that I don't have to explain in minute detail, but if it means saving a 3800 from destruction; I will.
Which year?
The last couple of years, you could run regular in the supercharged engine. You loose a bunch of power, but save a bit on the overpriced premium fuel.
The last couple of years, you could run regular in the supercharged engine. You loose a bunch of power, but save a bit on the overpriced premium fuel.
simple you just showed us why he picked that username
Yes, you would be doing harm. Any boosted motor IMO needs premium at a minimum. The knock sensor will retard timing to protect the motor but remember it's reactive. The motor has to knock first which is bad.
If you keep it out of boost you will be ok. Learn to drive with a light foot. Doesn't really make sense though when a fillup with premium is only a couple bucks more. You could more than make up the difference by driving a little easier. I run my turbo 3.8 on a minimum of 108 octane all the time for safety.
Alright, here we go:
Octane means the fuel's ability to resist detonation. There are certain times when you want the fuel to detonate; and other times you don't.
Increased compression; whether built in or added by a supercharger, causes heat. Heat is what ignites the fuel.
You don't want the fuel to detonate before the spark ignites; if this happens, the flame front from the compression ignited fuel will collide with the flame front from the spark ignited fuel. Now whether than having a nice slow burn, you now have a violent explosion!
That violent explosion (commonly referred to as pre-detonation or ping) is what breaks piston rings and punches holes in the top of pistons.
Broken piston rings will cause heavy oil consumption and a huge plume of blue smoke emitting from your tail while driving down the freeway.
Octane means the fuel's ability to resist detonation. There are certain times when you want the fuel to detonate; and other times you don't.
Increased compression; whether built in or added by a supercharger, causes heat. Heat is what ignites the fuel.
You don't want the fuel to detonate before the spark ignites; if this happens, the flame front from the compression ignited fuel will collide with the flame front from the spark ignited fuel. Now whether than having a nice slow burn, you now have a violent explosion!
That violent explosion (commonly referred to as pre-detonation or ping) is what breaks piston rings and punches holes in the top of pistons.
Broken piston rings will cause heavy oil consumption and a huge plume of blue smoke emitting from your tail while driving down the freeway.
If it says recommmended it means your car's computer can compensate for the lessor octane by programming and simply put out less power under boost or whatever its called with a supercharger.
If it says required use it may damage the engine using lower octane.
Try running it checking mileage with higher and lower octanes and see what happens. My Subaru WRX which requires 91 does lose a bit of mileage and noticable amount of power however its peaky(eg all at once).
If it says required use it may damage the engine using lower octane.
Try running it checking mileage with higher and lower octanes and see what happens. My Subaru WRX which requires 91 does lose a bit of mileage and noticable amount of power however its peaky(eg all at once).
But the point you guys are missing is that the timing retard is reactive. The computer has no idea what octane is in the car. The engine has to knock first and continue to knock for the timing to be retarded. The 3.8 and 3800 is a very stout motor but I can tell you from experience that it is possible to break it.
I had my turbo car all the way back in college when I couldn't afford gas and ran it on 87 for a couple years. But I also had a knock detector and a chip burned with only 18 degrees of timing. My advise if you run the cheap stuff is to keep it out of boost and you will be fine. I could only get away with 7psi with no knock vs 15psi with 91.
you bought a performance engine for a reason. don't cheap out on fuel or damage will occur!
simple, you're not going to put low octane fuel in that supercharged 3800 now, are you?
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