Octane requirements

[camaro69_4542003]

OK sorry i noticed its only the euro spec busa's have the o2 so sorry about that , kinda odd they didnt use one seeing as its alot more flexable and more controlable to the a/f ratio for both performance and reliability. Usually the fuel maps of like a car are for the a/f ratios at the given rpm and engine load based off the readings. Never really messed with the emissions equipment on my busa just assumed since its efi it would use an oxygen sensor. Learn something new everyday lol

 

[04gtstang]

(Wag @ Nov. 26 2006,15:43) When I first got my Busa, I used 91 octane.  Then someone here stated that the Busa compression ratio is really quite low and that 97 octane is better for the engine.

I tried it and saw an immediate improvement in gas mileage and in power.  Something like going from 33 mpg to about 36, typically.  I've never gone back to high octane.  It just does not do the Busa engine any good, apparently.

If you're interested in a scientific approach, you can't get better than your own experimentation.  Try it yourself and see what you get.  Bear in mind that gas mileage is not the only factor which determines how well an engine will run but it's a fairly good bet that if the mileage drops off on you, then something is definitely wrong.  

Do two or three tanks of each octane and measure the results on the third tank.  That way, you can be relatively certain that one fuel is not contaminating the results for the other fuel.

Report back your findings and call yourself the best scientist you can ask for!

--Wag--

Wow, that seems like pretty low milage there man.

In the past 300+ miles, iv adverged 49MPG. And this has been confirmed by the miles ridden and the amount of gas used. And im not just putting either....I lay back on the gas pretty good and fairly often while cruizing with my friends/family....and my engine only has around 750 miles on it as of now. Not even fully broke in lol.

Dealers and other people said that the bikes get around the mid-high 30s-low 40s. If I stay completely out of the throttle, my gauge stays pegged @ 50MPG.


And BTW, o2 sensors arent the best tools for the EEC to use to determine the A/F, as its seeing the after image and lags behind on adjustment.

Manifold pressure and IAT sensors work just fine....if you know how much vacuum/pressure is in the air box, and you know what temperatre it is...then you can determine how much fuel to spray in, along with how much timing to add in (timing should vary with how hot the air is) .
T
he 02 would just restric exhast gasses....and since alot of you are worried about how much a weld is sticking up in your exhaust path, because it robs power....then deleting the 02s for the US version was a good idea

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