Originally Posted by shenmecar (Post 6376692)

well your Z is turbocharged

i put midgrade in my mdx and its fine

Originally Posted by Death2Theft (Post 6379839)

No it's not she's just a basemodel poser.

Originally Posted by Lomac (Post 6376969)

Kinda... Here's the Coles Notes of it:

If your car states that it "Requires Regular unleaded", you're fine putting in 87. If it "Requires Premium," your minimum octane is 91. If it "Recommends Premium," you can put in Regular as the car will adjust the timing to prevent detonation, though at a possible loss of horsepower and/or fuel consumption.

Conversely, putting 94 octane into an engine that only requires 91 or less can also have an adverse effect. Higher octane means a higher detonation point. An engine that is designed to run on a lower octane needs to run hotter in order to try to burn the higher octane. As a result, you end up with hotter engine temperatures, more unburnt fuel going through your exhaust (which will lead to a premature death on your cats), and worse fuel mileage.

The only reasons why you would put higher octane into your engine than what the manufacturer recommends is if you've modified it in such a way that you have higher compression, and/or are running some type of forced induction.

Originally Posted by Rikaro (Post 6379963)

thank god for this post. I was getting dumber every post I read down

Originally Posted by Iceman-19 (Post 6379505)

First part is bang on, 2nd part, not so much. You can run whatever fuel you want as long as it is above the minimum the engine requires. Running 94 octane on a vehicle that requires 86/87 isnt going to not burn the fuel, it will still burn it, as it will only inject what it needs into the cylinder. It will just take a longer time to burn, so the burn will not be as complete. If you have OBDII, the car may adjust for this, adjusting injector pulse width, plug firing times, timing, etc. It may just run like a bag of ass. Unless you vehicles REQUIRES a certain minimum (i.e. 91/94), or its boosted or very high compression, run 87.

Originally Posted by pandalove (Post 6382162)

Shell gas only goes up to 91 V power... and they say the develope with ferarri ... but doesn't ferarri cars require 95octane?... am i missing something here?

Originally Posted by Bonka (Post 6382188)

95 is likely the RON rating (Europe), which would be 91 octane (RON+MON/2) in North America.

Speaking of Shell, what's the point of having 2 nozzles for 91?

Originally Posted by jlenko (Post 6382724)

There are a few cars out there that WILL see improved performance from using a higher octane... say, the factory timing for 87 octane is knocked back a bit, and the manufacturer actually has enough tune in there, so if you're running, say, 89 octane... it will advance the timing a bit more to make a little bit more power.

BUT the cost of the higher octane vs the minute amount of difference you'll ever see there - not worth it!