Mixing RON95 with RON97

[g4i8y0t]

I have one question: If we mix RON95 with RON97 petrol in 50:50 ratio, will the petrol become RON96?

 

[Veloc]

LOL.. Theoretically it should be. But why? Just use RON 97 if yours is high performance engine. Even with RON 97 in our country, I don't think it is enough for high performance engine. A lot of jap high revving engines are tuned with RON 98 or RON 99. So even RON 97 is not enough to unleash the full power. Let alone RON 96. Fk the gomen.

 

[rakesh_v6]

http://www.zerotohundred.com/newfor...s-the-difference-between-ron95-and-ron97.html

 

[Izso]

Automotive Gasoline FAQ

6.15 Can I mix different octane fuel grades?

Yes, however attempts to blend in your fuel tank should be carefully planned. You should not allow the tank to become empty, and then add 50% of lower octane, followed by 50% of higher octane. The fuels may not completely mix immediately, especially if there is a density difference. You may get a slug of low octane that causes severe knock. You should refill when your tank is half full. In general the octane response will be linear for most hydrocarbon and oxygenated fuels eg 50:50 of 87 and 91 will give 89.

But taking the average isn't always the case. It's a case of whether the chemicals in petrol play along together or not. For all you know mixing 95 with 97 might just give you slightly more than 95 octane but below 96.

Kinda like the same concept of some octane boosters. Dump in RON100++ into a RON95 mix might increase your octane but not significantly.

If you don't quite get it, think of whisky and water. They mix. But how does it taste? Watered down? What if you throw in a highly concentrated liquor like Absinthe (90% alchohol) and mix it with water would it still be watered down?

It's all subjective and since we'll never know the true formulation of petrols, mixing it around isn't going to be beneficial to you. Might as well tune your car to work with 95 and be happy on the cost savings.

 

[g4i8y0t]

LOL.. Theoretically it should be. But why? Just use RON 97 if yours is high performance engine. Even with RON 97 in our country, I don't think it is enough for high performance engine. A lot of jap high revving engines are tuned with RON 98 or RON 99. So even RON 97 is not enough to unleash the full power. Let alone RON 96. Fk the gomen.

Well, my engine has low compression ratio, 9.4:1. I prefer to advance the ignition timing a bit to increase low end torque and engine response. However, when using RON95 there is some minor engine knocking at 2-3k RPM and major one at above 5500 RPM. I believe using RON97 will help to solve the problem, but the problem is it's expensive... So I came up with the idea of mixing them.

 

[Veloc]

Haha... But like what Izso said, mixing the 2 in equal proportions doesn't yield the supposedly RON no. So better not la... Just be mild on acceleration at where it knocks or, maybe use a boost cooler or hydrogen fuel enrichment? High initial startup but it pays of around a year.

 

[cvkit17]

Erm..if i could remember from my old suffering days in Uni, RON95 and RON97 are mixed from very high octane fuel with very low octane fuel. Note that i used the word "very", which means RON1xx mix with fuel with RON1x (if not mistaken, and of course, other additives). So mixing RON95 with RON97 will indeed increases ur RON number but it wont be a significant one i.e. u would not able to get RON96.

Since u had tuned your ignition timing, its either u use RON97 (if there's totally no knocking) or you tune back the timing to suit RON95. The power loss would not be so significant unless you are lapping the streets. Of course with RON97, you may able to maximize your stroke length to give better power to your engine.

Well...i would say fun things do come with a price.

 

[jeffayn]

...Of course with RON97, you may able to maximize your stroke length to give better power to your engine.

Well...i would say fun things do come with a price.

It is tempted to say with RON97, you may able to maximize your stroke length to give better power to your engine. BUT sadly, it does not.

The invention of various RON is actually to coupe up with the modern engine design, but not all car come with modern engine design that require RON97 RON102 or RON110 because car manufactuer knows these supply of higher RON is can be hard to find and costly

Mixing RON95 97 does not give RON96 likeness, the petrol will stay put as it RON95 RON97 mixture, they are miscible but octance property does not change because we mix them up like that, or else the petrol company will just be producing high RON and mix it to lower RON for the conveniences sake.

Knocking is always misunderstood as pre ignition, but knocking in simple way to explain it is the detonation of fuel, pre ignition is like a more serious problem, sometime intentional too (in racing). Knocking hurt the car, but pre ignition will kill your engine

If you car is running without knocking with 95, if you feed 97, 102 or 110 or 130, your car will not perform any better

in fact 80% of the car I tested in local market , does not knock with RON 95

often time , I got saga, myvi coming in telling me 95 is no good to their car, but i will refill the tank again and prove them wrong... Q: why they hear knocking when they pump RON95
Ofter found issue is the petrol station they use. Their petrol is contaminated. 2 out of 10 petrol station in Malaysia got into severe gasoline contaminated issue, Cause no 1: flood Cause no 2: manmade

often time you will see petrol station close down for weeks or days, because the reservoir need to be empty and to clean it, to seal up the cracks.

by all means... when you pump the fuel, think do you really need it?

 

[cvkit17]

If you car is running without knocking with 95, if you feed 97, 102 or 110 or 130, your car will not perform any better

Agree..as many modern cars are equipped with variable timing to control the ignition using a knocking sensor (eg. nissan sentra). When the ECU senses knocking, it will changes its ignition sequence and timing to suit the explosion temperature of the fuel. Lower RON explodes at lower temperature. The reason why I mentioned that RON97 gives you more power is when you tune ur car to run only on the higher RON. But if your car is tuned to run on RON97 and its already the max stroke u can go, using RON999999 also no use

Many cars nowadays even can run on RON92. Most drivers will experience knock when they are going uphill. Dat's when the RPM is low. So use lower gear and speed uphill but dont crash

 

[g4i8y0t]

Thanks for the info guys. One more question: Why is it that my engine runs smoother with RON97? During idle also the engine vibrates less compared to when I'm using RON95.

 

[cvkit17]

I believe dat has something to do with the additives they mixed into the fuel. If your car can run on both 95 and 97, then the difference would be near to 0. Just like Shell, RON97 is V-power..where else RON95 is fuel saving. So the additives must be different. What petrol are u using btw hehe...Im using RON95 Petronas..quite ok so far. Caltex is my fav fuel but their stations are like needle in a haystack. So i switched.

 

[g4i8y0t]

I use Shell RON95 coz wanna collect Bonuslink points, hehe. The fuel quality is quite okay. Sometimes I use Caltex RON95. After advancing the ignition timing, I mix Shell RON95 with V-Power RON 97 in 2:1 ratio to avoid knocking. It does help a bit. Plus, my engine runs smoother too.

Some say that Shell RON95 causes engine knocking, other brands do not. Is that true?

 

[6UE5t]

I'd say should be fine to mix and it would help cause I've done this kind of mixing many2 times before. Theoretically it should give you the avg. of 96 with 50:50 mix but I cannot be sure if it's correct cause never really care to get the sample measured, but what I can tell you is that it will indeed help and will surely be better than 95.

 

[zuruzuruz]

sorry to be slight off topic.. huhu.. since someone brought this up.. dear sifus or gurus, ur wisdom is much appreciated..

i managed to increase my engine's CR ~10.5:1 with stock internals from my original CR, which is 9.5:1. my foreman advise me to use 97, BUT, is it too much of a risk to tune my engine using 95 with that compression? i dun think 10.5 is that high still. :( any infos/suggestions/experiences?

thanks in advance..

 

[g4i8y0t]

sorry to be slight off topic.. huhu.. since someone brought this up.. dear sifus or gurus, ur wisdom is much appreciated..

i managed to increase my engine's CR ~10.5:1 with stock internals from my original CR, which is 9.5:1. my foreman advise me to use 97, BUT, is it too much of a risk to tune my engine using 95 with that compression? i dun think 10.5 is that high still. :( any infos/suggestions/experiences?

thanks in advance..

Bumping up your compression ratio by that much, you definitely need to use RON97 + some tuning or even aftermarket ECU I think. You need to ask the sifus...