Push mower high octane

[SwampSurvivor]

Would a push mower have an advanced enough ignition system and high enough compression to take advantage of high octane fuel?

Mine is just a coil that fires at the same time every revolution. And I know my 20 year old worn out lawnmower engine has very little compression.

 

[kschachn]

Less chance of pre ignition, cooler running, more power, more cutting per gallon (cpg), lower emissions, less smoke, less noise, and few others i cant remember at the moment

What a bunch of nonsense.

 

[javacontour]

Anyone else use high octane?

Probably a waste, I believe small engines like these have low compression ratios.

A Honda GCV160 has an 8.5:1 compression ratio.

Briggs and Stratton L-head engines are more like 6:1

You could probably run 85 AKI fuel in these. AKI = (RON+MON)/2 as that is how we measure it here in the land of "Freedom Units"

Your 99RON is around 93-94 AKI here in the US.

And it's still a total waste for the typical small engine.

 

[IndyIan]

I usually run 91 or 93 octane so I don't have to keep track of different fuels and its ethanol free. Everything 2 stroke gets 32:1, and sometimes the 4 stroke stuff gets that too! KISS is what I'm going with these days!

 

[MParr]

Anyone else use high octane?

Me!

 

[mightymousetech]

Anyone else use high octane?

Always used high octane, was the only gas available without ethanol.

 

[slybunda]

Would a push mower have an advanced enough ignition system and high enough compression to take advantage of high octane fuel?

Yea they used variable valve timing with a knock sensor setup so can advance and retard timing as needed and use coil on plug ignition system with standalone management to eek out every bit of power from the go go juice.

 

[The Critic]

I read somewhere to use 89 due to fuel stabilizer having a negative effect on octane.

 

[supton]

I use last year's E10 until I run out of it. The I buy... more E10. 87 octane only.

 

[Donald]

Old people call it "high test".

Around here the E0 is always high test, probably 92 or 93 octane. So I buy the E0.

While the compression may not require high test gas, I am thinking OPE is more likely to have deposits. So high test may help with cylinders with deposits. (But just a guess).

And OPE gas may sit around for awhile loosing octane until used up.

 

[slybunda]

So can high octane fuel sit for longer before it gives trouble?

 

[kschachn]

I read somewhere to use 89 due to fuel stabilizer having a negative effect on octane.

Only by diluting the fuel. It would depend on how much you’re actually adding.

 

[Popsy]

I am running high octane (98) too, just because that's the one I can find with the least ethanol. 15L per season won't make much of a difference vs the regular 95/E10.

 

[Dennywires]

87 is fine.. i spend the extra on 93 with the hope and prayer it will last longer. i top up a 5 gal can and get a year out of it mowing and in the snow thrower. i have a friend that fried a small engine using higher octane fuel and mixing NOS octane booster.

 

[kschachn]

So can high octane fuel sit for longer before it gives trouble?

No.

There’s so much misunderstanding about what the octane rating means and does not mean, at least from a physical and chemical standpoint. Reading and believing the numerous pages of pure garbage on the Internet doesn’t help.

 

[slybunda]

Does octane lower over time?

 

[wpod]

Good weather coming next week so got the lawn mower and pressure washer topped up with high octane 99 RON stuff.
With high octane does that mean i cut grass faster and get more pressure from pressure washer? Lol

Sure why not.h

 

[kschachn]

Does octane lower over time?

Now I see the real intent of this thread.

Read up on how an apparent octane rating is and can be achieved. You can answer your own question(s) there.

 

[JavierH19]

Higher octane is virtually useless in low compression engines but I recommend high-octane gas if you plan on storing gas for years for some reason as the gives a bufferr on octane degradation. Engines like the ford 3.3 actually benefit from high octane because it's a very high comp gas engine. But id recommend being sensible and using that gas in a season so you dont have to buy high octane just the regular 87 with a bit of stabil and what isn't used should be taken out and dumped back into the can and just dumped into the vehicle.

 

[Spur]

Non Ethanol with a little MMO