So my father just purchased a brand new supercharged V6 Frontier 4X4 with the "off road" package. Needless to say I'm pretty psyched to get home for Father's Day and check out the new ride.
I do have a quick question. What is the reasoning behind using premium gas only? Is it a higher compression engine because of the Eaton supercharger... or is it just a bunch of hype to make you spring for the high-test stuff?
Supercharged V6 Frontier....!
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MaineExport
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Mayhem_J30
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Nismo_Freak
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You have two forms of compression ... static and dynamic
Static compression is the compression you achieve by mechanicals usually around 300 rpm, ie. pistons
Dynamic compression is the compression you achieve at a specific rpm. On a FI car you are forcing air into the chamber which will bump your compression at that specific stroke. When your not under boost your compression is the static compression roughly.
Now even n/a cars can have lowered static compression on the low end while gaining compression on the big end. It's due to cams, headwork, and any other top end specific flow mod.
Say you ran 7 psi of boost. If you had a static 9:1 compression ratio the dynamic ratio could be around 13:1. Obviously 87, or 91 can't keep up at this level so 93 is the only option. Even at 13:1 the ECU will retard timing to prevent detonation.
BTW, the above 9:1 --> 13:1 is a guestimate... you'd have to know your cam specifics, headflow properties, blower cfm @ specific boost, etc. to correctly figure your compression ratio.
Static compression is the compression you achieve by mechanicals usually around 300 rpm, ie. pistons
Dynamic compression is the compression you achieve at a specific rpm. On a FI car you are forcing air into the chamber which will bump your compression at that specific stroke. When your not under boost your compression is the static compression roughly.
Now even n/a cars can have lowered static compression on the low end while gaining compression on the big end. It's due to cams, headwork, and any other top end specific flow mod.
Say you ran 7 psi of boost. If you had a static 9:1 compression ratio the dynamic ratio could be around 13:1. Obviously 87, or 91 can't keep up at this level so 93 is the only option. Even at 13:1 the ECU will retard timing to prevent detonation.
BTW, the above 9:1 --> 13:1 is a guestimate... you'd have to know your cam specifics, headflow properties, blower cfm @ specific boost, etc. to correctly figure your compression ratio.
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MaineExport
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Mayhem_J30 wrote:you should know all this by now maine..lol. there's probably countless threads out there about premium fuel and why.
Haha... thanks Mayhem.
I thought about it after posting.... hmmm, maybe I should have SEARCHED before asking!!! Oh well, I'm a tool sometimes.
Thanks Nismo-Freak for the indepth answer... I was aware that the higher octane helps prevent detonation... I wasn't aware of the static vs. dynamic compression and how they differ on a force fed engine.... thanks again!
LTJJ... I'll get pics this weekend for sure... Maybe we'll line all the Nissans up again for another family photo!
