RON95 test on my E34 M50

[turbosnail]

Latest update:

Filled her up at the same pump at the same Petronas station:

Amount of RON95: 48.327L
Mileage traveled: 419.6km
Driving condition: Urban
Fuel consumption: 11.52L/100km

1. A slight increase in fuel consumption again compared to last fill up.
2. Should be 100% RON95 since this is the third fill up.
3. No change in driving habit.

To be continued....

Latest update:

Filled her up at the same pump at the same Petronas station:

Amount of RON95: 53.277L
Mileage traveled: 476.3km
Driving condition: Urban
Fuel consumption: 11.19L/100km

1. Fuel consumption dropped 3% compared to last data.
2. Purer RON95 fill up.
3. No change in driving habit.
4. Last RON95 fill up. Next fill up will be RON97 to conclude the differences in fuel consumption between Petronas RON95 and RON97.

To be continued...

 

[turbology]

Carbon (arang) itself is flamable. So carbon deposit will help combustion in the block gone beyond control, normally earlier than that of your spark plug.

Why sports car engine need high RON? It's simply because they are of high compression ratio and high rev.

The "Arang" you use at home are flammable, not the carbon deposit in your car
With carbon build up in engine block, it reduce the 'space' in combustion camber, thus raise up your compression ratio. So your car are more prone to pre-ignition with lower RON grade fuel.

Not all high compression engine need higher RON fuel.
Not all sport car need higher RON fuel.
Example : 2009 Honda Civic with Compression 10.6:1 able to use RON91
While, Mitsubishi EVO X with compression of 9.0:1 recommend RON97 fuel.

Cheers

 

[turbology]

btw, i thought M20 engine dont have knock sensor, so why would the ecu adapt to the fuel octance accrodingly??

Simple. Your car is cater and tune for RON91 since day 1 from factory. So, why you have been paying extra for RON97 ?

 

[morpheus5039]

Simple. Your car is cater and tune for RON91 since day 1 from factory. So, why you have been paying extra for RON97 ?

bcos i heard knocking last time when i fill up with ron92...

 

[turbology]

Well, check your car manual. Is the best to find out your minimum fuel requirement.

 

[anakin]

bcos i heard knocking last time when i fill up with ron92...

Me too, even with ron95 heard knocking oso....

 

[bluepanther]

THIS IS NOT AN ADVERTISEMENT.

.....been following this thread and there's only one thing i can say and would like to share.

1994 E34 520i 24v vanos (A).

Ive tried RON95 and whenever i drive my car i can 'hear' as if my car saying 'please dont fill me up with RON95'

Whenever i fill up with RON97 there is almost no comment from my car.

Whenever i fill up with V-POWER i can hear as if my car saying 'WOW i love it...please fill me up somemore'.

This is also not a phsychological feeling......

 

[morpheus5039]

Me too, even with ron95 heard knocking oso....

i dun hav problem with ron95

 

[mizhan]

i dun hav problem with ron95

me neither.. engine lazy no matter which fuel

 

[erica34]

Not all high compression engine need higher RON fuel.
Not all sport car need higher RON fuel.
Example : 2009 Honda Civic with Compression 10.6:1 able to use RON91
While, Mitsubishi EVO X with compression of 9.0:1 recommend RON97 fuel.

Cheers

there's a turbo somewhere between the compression ratios... that might be a factor too

 

[pussy]

THIS IS NOT AN ADVERTISEMENT.

.....been following this thread and there's only one thing i can say and would like to share.

1994 E34 520i 24v vanos (A).

Ive tried RON95 and whenever i drive my car i can 'hear' as if my car saying 'please dont fill me up with RON95'

Whenever i fill up with RON97 there is almost no comment from my car.

Whenever i fill up with V-POWER i can hear as if my car saying 'WOW i love it...please fill me up somemore'.

This is also not a phsychological feeling......

wow i did not know you could listen to your car talk !!

hidup RON97 :top:

 

[morpheus5039]

me neither.. engine lazy no matter which fuel

If your engine is lazy then my engine can say "sleeping", hahaha!

btw, i feel better mileage after changing from shell95 to mobil95...
I FEEL ONLY(bcos my mileage is dead)

 

[turbology]

there's a turbo somewhere between the compression ratios... that might be a factor too

There's alot of factor besides NA and FI.
You have to consider Miller Cycle, Atkinson Cycle, and Rotary too, which is my point : higher compression don't necessary need higher RON

 

[astroboy]

Variable timing engine design allows timing to retard/advance to a greater degree than non variable timing car. That's why u'll see 10.6:1 compression engine can retard timing all the way down to using RON91 without issue.

The measurement of compression is taken by compressing the air in the combustion chamber without running the engine. Once turbo engine is running the FI would boost the combustion pressure and that's why they can't use low RON fuel. I still think detonation has everything to do with high compression..

 

[stlee29]

If your engine is lazy then my engine can say "sleeping", hahaha!

btw, i feel better mileage after changing from shell95 to mobil95...
I FEEL ONLY(bcos my mileage is dead)

I also have the same opinion.:top:

 

[turbology]

Variable timing engine design allows timing to retard/advance to a greater degree than non variable timing car.

Varaible timing in VANOS actually mean the valve timing open/close early or late. Is not about the spark timing lah... aiyo..

The measurement of compression is taken by compressing the air in the combustion chamber without running the engine. Once turbo engine is running the FI would boost the combustion pressure and that's why they can't use low RON fuel. I still think detonation has everything to do with high compression..

The fuel requirement is more directly link to the peak cylinder pressure. If is at higher side, including FI, higher RON fuel is usually recommended.

Cheers

 

[turbosnail]

Latest update:

Filled her up at the same pump at the same Petronas station:

Amount of RON95: 53.277L
Mileage traveled: 476.3km
Driving condition: Urban
Fuel consumption: 11.19L/100km

1. Fuel consumption dropped 3% compared to last data.
2. Purer RON95 fill up.
3. No change in driving habit.
4. Last RON95 fill up. Next fill up will be RON97 to conclude the differences in fuel consumption between Petronas RON95 and RON97.

To be continued...

Latest update:

Filled her up with RON97 at the same Petronas station:

Amount of RON95 consumed: 44.391L
Mileage traveled: 409.2km
Driving condition: Urban
Fuel consumption: 10.85L/100km

Total RON95 consumed: 240.98L
Total Mileage: 2145.6km
Final fuel consumption: 11.23L/100km

Urban fuel consumption when RON97 was used before RON95 fill up: 11.56L/100km

Observation:
When switch back to RON97 I could feel a noticeable difference. The engine becomes more responsive. When floored the pedal on Pg Brdge I could the car was more eager to go faster than when RON95 was used.

Fuel consumption:
It seems to me the fuel consumption is better when RON95 with newer Petronas additive is used(~3% improvement).

Conclusion:
I don't know if this is only the case for my car, or it is for all E34 with the same engine model and capacity as mine. The difference of fuel consumption on Urban driving condition is insignificant in my case. I have not had the chance to try RON95 on highway yet. But it would be interesting to see if it differs. With RM0.25/L fuel price difference between RON95 and RON97, we are talking about RM16.50 difference(assume 66L fill up) per full tank. Also, that would be RM60.245 difference per monthly fuel expenditure at the same amount of fuel used for last month. Naah, I can live with that. But it will remain to be seen if there is any significant difference when it comes to highway mileage. I will try it when I have chance to go long distance travel down to Singapore again. At the moment at urban driving, I think I will stick to RON97. Not much difference lah. Somemore car feels more lively when RON97 is used hehe