95RON fuel


T

Tim

2000 EK9 Type-Rx
Joined
May 27, 2007
Messages
1,123
What would happen if I put some 95RON fuel in the EK9? I had to drive about 40 miles with the petrol light on the other day, looking for some SUL.

Would it just be down on power or would it cause problems with the engine? Obviously I wouldn't fill up with it, but I might need to stick £5 in one day.
 
Thanks. I'm sure I read someone's car on this forum wouldn't even start with 95..
 
yer maybe if its very highly tuned but even then i doubt it 95 is fine just not for power :drive:
 
The fuel is a lower octane so itll ignite at a lower flash-point. e.g. Under harsh running conditions, like lots of high rpm driving and lots of heat (i.e. on a hot day) the fuel may ignite at too low of a temperature, generally from the heat of the exhaust valves.
When this ignition event (known as 'engine-knock') occurs early on in the compression stroke, the resulting gas-expansion from the fuel is almost trying to force the piston the back down the bore, of course it cannot actually force it back down the bore because of the momentum of the reciprocating mass. ....but what it can do is hammer the bearings causing light scoring on your bearings rapidly affecting the clearences. On a highly powered turbo application this can kill the setup very fast. I.e. spin a bearing.

This engine-knock produces sounds in a certain frequency range, the factory knock sensor on the stock EK9 engine (and a some other honda engines with knock sensors) is basically a microphone that picks-up this and filters it to leave the relevant frequencies. The ECU reads the amplitude of these frequencies and within milliseconds retards the digital timing short-term then slowly raises it back up towards stock until its detected again. Since it keeps swinging past the optimal point in the sort-term adjustments, its constantly working out the average for the long-term adjustments.

So lets say you run your car on 95 all the time. It'll run on it yeah, it'll be 'OK' with it. but its not ideal. And you defniteley shouldnt be hammering it if you DO have to put low octane fuel in. ...Since the factory tuned these motors on 100oct its best to use fuel cose to that to get optimum milage and power out of them. Afterall EK9 owners shouldnt be running them on supermarket fuel:((
 
Is shell vpower ok? I've been running it on my Ek9 since I bought it. I was reading an article in the paper a couple of days ago stating that a university in america had teamed up with a british university and they carried out tests on the performance of vpower/bp ultimate, etc compared to "normal supermarket fuel" and the difference was nil. Their conclusion was that people had been wasting their money using vpower over normal fuel. Normal fuel here in scotland costs 106.9p a liter and vpower is 115.9p per litre at the moment but its meant to be going up again! :( Personally I'm gona keep using vpower on the basis of what you have said EK9turbo.

But what do you all reckon about the article and has anyone else read it?
 
Basically you run the car on the fuel it was tuned for.

From the factory the tuning has compensation in it to allow for low-quality fuel. Whereas a tuned car tuned on X fuel (turbo setups WILL struggle) will be emmisions passable since the owner will only operate the car on that fuel.

The factory HAS to make leighway for these possibilites to keep reliability. But if you take a factory europan car tuned for 95octane then running it on 100 octane wont gain you any power or performance. You run the motor on the octane it was tuned for, simple as that. :nice:
 
ramboteamjon said:
But what do you all reckon about the article and has anyone else read it?
Click to expand...

not read it but i have an idea what they were getting at.

depends what fuel the car was and what it was mapped on,

I.E if you mapped a car on 95 ron, so it was at its optimal performance and then you put 98 or even 100 ron in it you wourlnt see a power increase as teh ECU woudl not know it was in teh tank and all your ignition parameters have been mapped for 95,

you woudle need to advance the ignition map to make use of the higher octane rating to get an increase.

if they did this they woudl of seen a gain for sure.....



whan i was in germany with my ek9 teh fuel was 100 octane and the car went allot better you can tell that the ek9 was originally mapped on it after about 40 miles of having it in the tank, it pulled so much better in the lower revs. :drive::drive::drive::drive::nice::nice::nice:

was a shame to come back to uk and go back to 98, car is not as smooth in the lower revs and less tourquey. prob cos teh ignition advance is beng retarded out of teh map by teh ecu, :((
 
Also to bear in mind, quality fuels have combinations of additives tat are beneficial to the engines long term life. Most supermarket fuels are very high in 'detergent additives'. Youll notice it even says this on some of the pumps!

V-power, or BP-ultimate are great choices for the factory EK9.

Remember the octane rating is directly relevant to the flash-point of the fuel. higher octane = higher flash-point. (min temperature for spontaneous ignition)


Right click and download this video of MoTeC doing a fuel comparison test
http://www.motec.com.au/filedownload.php/MOTECFUEL.wmv?docid=2496

here is the summary of their findings:
MoTeC said:
Fuel comparison tests were performed on three leading brand high octane fuels, Shell V-Power Racing and two Premium 98 Octane fuels (brands X and Y), under strictly controlled conditions. Tests were performed using a current model Mitsubishi Evo IX 2ltr turbocharged engine* mounted to a purpose built engine dynamometer cell. Tests were conducted using the standard Mitsubishi ECU and a MoTeC Plug In M800 ECU. No modifications were made to the engine.


The results of the testing clearly indicated that:


Tuning of engines is required to obtain the maximum benefit from any fuel.

There can be significant performance benefits to the fitting of a MoTeC Engine Control Unit (ECU), even without engine modifications.

Shell V-Power Racing 100 Octane fuel consistently delivered significantly more torque (up to 10.7%) and engine horsepower (up to 4.6%) than other commercially available high octane fuels in the retail market.

In addition, based on limited testing, Aviation Fuel (Av Gas) was also tested.
Initial results showed that V-Power Racing was superior in its detonation resistance and able to make more power than the tested Av Gas.

*Mitsubishi Lancer, Evolution IX, 4G63 2ltr, 16 valve DOHC MIVEC intercooled, turbocharged engine
Click to expand...
 
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