[amit]

Hi guys... I put in about 38 ltrs of 98 fuel in my car a few days back. I have driven around 180kms so far. My car was always being driven with Speed93 before this. So here is my expereince with 98.

120kph was now at 3600rpm instead of the previous 4000rpm.

I didn't find that happening in my car. I used to do 100kmph at about 2900-3000rpm and the car still does 100kmph at the same rpm. Idling has become a little smooth and so has throttle response. But the improvement is extremely marginal in my car. maybe because I have always used Speed93 so i guess my engine was pretty clean as it is so there isn't much 98 octane could do!
Will update on improvements in mileage later. I am planning to tank up once more on this fuel and then calculate the average mileage of 2 tankfulls.

[speedsatya]

hey amit,

i am sure i felt the difffernce though i did not check it again as the car was with me only for a few hours.
would check it and let you know.

by the ways ,if i am not wrong ,dont u own a S10 .there was noticeable differnce in the red ikon as well.

[Rehaan]

Originally Posted by Shan2nu

Well Rehaan,
most websites say that fuels have 3 octane ratings.

1. RON - Research octane number
2. MON - Motor octane number
3. PON - Pump octane number.

PON is usually (RON+MON) / 2 and that is the figure printed on some pumps. it gets very confusing since we don't know if the PON is the standard way of selling fuel or some pumps sell RON rated fuels.

Hey Shan,

This is what i have been saying for the last 8months! lol

To quote from this thread

Originally Posted by Rehaan

This is what has been irritating me a bit in all these "high octane discussions", but due to lack of proper doccumentation on the indian fuels i havent managed to paint a perfect picture.

There are three basic ways of getting an octane rating

RON - Research Octane Number - Constant speed of 600RPM, in lab conditions, with a lower inlet air temp.
MON - Motor Octane Number - A harsher test more like real world conditions 900RPM.
AKI, AON, (R+M)/2 - Anti-Knock Index, Average Octane Number, - This is basically the average of the RON and MON.

Ok, so having understood that, its safe to say that the RON will always be higher than the MON for the same fuel.
Marketing takes advantage of this fact and states the RON number in some cases (which is what i feel is happening with Speed 97).

USA however, uses the AKI (average of the RON&MON) system for rating the octane of fuels, as marked on their pumps etc.

This is kind of how audio companies advertise loudness in Watts PMPO (PEAK Music PEAK Output), when what is really a better guide is the RMS Wattage (Root Mean Squared).

cya
R

ps - i seem to remember when power was first launched that ACI said it had a RON of 87.

RON being the highest, and knowing Indian mentallity, i think it would be safe to assume that all "marketed octane ratings" are RON.

Amit, thanks for clarifying that the pump clearly states RON.

Originally Posted by Shan2nu

Well if you're that sure about it being 98 RON ratings, then why fill it in the first place, unless your car has a comp ratio of over 10.1:1........

The 98RON would be around 90MON or 94AKI, which makes sense for even a 9.1:1 compression ratio if i am not mistaken.

Kbk75, i think stating a deviation of 10points between RON and MON is a bit extreme...atleast in the octane range that we are discussing. Its more like 7-8points.

cheers
R

[kbk_75]

Originally Posted by Rehaan

Kbk75, i think stating a deviation of 10points between RON and MON is a bit extreme...atleast in the octane range that we are discussing. Its more like 7-8points.

From what I know, most modern petrol world-wide has a sensitivity of around 10, not 7-8.

[amit]

i am sure i felt the difffernce though i did not check it again as the car was with me only for a few hours.

Even i am wondering how you guys got that difference and i didn't?

by the ways ,if i am not wrong ,dont u own a S10

Yes i do own a S10 and thats why i expected 98 to do more than what it did. On ACI's recommendation i have been using Speed93 and the difference between the performance with Speed and Speed93 is really huge. The Palio 1.6 has high compression ratio compared to cars comparable to it and hence i did expect more from 98. Still i'll tank up once more on 98 and check it again. As of now, as i said, the marginal difference is in the form of smoother idling and slightly better throttle response.

[normally_crazy]

Originally Posted by speedsatya

hey NC,
you are the one who is closest to this pump.so you can only answer this

Yeah it is a 24 hr pump.

[kbk_75]

Oh joy! That's great news! Thanks NC!

[normally_crazy]

fellas,

was going thru ikon manual and came across this !!

fuel specified - unleaded 87 octane but unleaded 95 octane and 98 octane can also be used

cheers

[kbk_75]

Well I'd imagine any petrol that at least meets the minimum required spec will be fine, but probably won't yield too much benefit, unless the engine's compression ratio is high enough to utilise it, in which case the minimum spec would be higher in the first place.

[Shan2nu]

fuel specified - unleaded 87 octane but unleaded 95 octane and 98 octane can also be used

No doubt about that, you fill 100 octane and your car will still run, but you won't gain anything from it.

An Ikon with 91-93 octane will work as effficiently as another Ikon running on 95 or 98 octane.

There won't be any difference in acceleration, unless your car is tuned for high octane. And if it was, then the manual wouldn't have included 87 octane in the first place. They would have recomended 95 octane and above.

U can give it a shot if you want, fill your car with 93 do a few 0-100s (using the gtech pro) then when ever you have 98 octane in your car, do another run (i bet you won't find any difference in accceleration figures).

Shan2nu

[kbk_75]

Well I'm gonna see if I can find this pump tomorrow morning! Hopefully I won't get too lost! Anybody know how far from the flyover this DAKC is?

[normally_crazy]

which flyover ? and yeah from vashi when u get on to the TB road towards thane u cant miss the punp its just before the DAKC on ur right !

[kbk_75]

Hey NC, can you just clarify this for me; I'm not familiar with the names of all the places in that part of town!

I get through the Thane creek toll naka, then go straight over the first flyover. The next flyover has the left turn which takes me onto Palm Beach Road. Do I take that left or do I turn left on the last flyover where you HAVE to either turn left or right and cannot go straight on?
I'd imagine it's the last one. And how far from this flyover is the DAKC Pump?

Thanks!

[normally_crazy]

kbk,
after the toll naka dont go over the flyover , go under the flyover u come to a signal , go straight and take a left after the signal - then straight and u hit a circle..straight from there , u pass days inn hotel to ur right...till u hit a signal - straight from here on too u climb on a fyover that takes u to thane belapur road - keep going straight and look out on ur right 2 mins after u leave the flyover - u will find the pump.

chherrs

[kbk_75]

Well, I finally gassed my car up at the pump today. Put in 38 litres and drove back into town in traffic. I'll have to go to the dealership to see if there's a way to set the petrol quality in the ECU and then see if there's a marked difference in the performance compared to 93.