Markus

This of course does not take into account Jap imports that are meant to run on 100 RON fuel, hence part of the reason jappers should run on 98 RON fuel.

Having said that, I did used to run my car (WRX Wagon) on 95 RON, and when/if I get a knocklink fitted, I will try a few tanks of 95 and see what the knocklink reckons to it, but to be safe I'd rather run on optimax.

Katana

I read an article the other day on the Oxford mail that made me laugh and cry. The advice given by the columnist, an "expert" in motoring says that a clutch should last the lifetime of the car.

LG John

Technically he is correct. Any UK subaru that is NOT modified can run all its life on 95 RON without problems and very likely without det. Granted 97 RON will be better.

Of course now that I've typed all this I'm now wondering if this is the case with the P1 which specifies 97RON Hmmm, I'd guess they'd be fine on 95 as well.

MRK_IV

Why would they run 'fine' if Subaru reccomends 97?

siwrx

lol they run alright the **** i bought mine off put 95 in it before delivery and the knock link cut the car after 5k til the **** drained out

salsa-king

well i run fine on 95...UK turbo full de cat car.
does feeel smoother on optimax.

but not every garage has 97+ petrol... what do you do?
remove your bot and fit a big petrol tank! lol

Phil

chrisp

LOL

AndyC_772

iTrader: (2)

Hm... it may be true that unmodified UK spec cars won't be damaged by running on 95 RON, although I personally wouldn't run a P1 or 22B type UK on that stuff.

Modified cars are a different can of worms entirely, though. Even the PPP for some years ('97 and earlier?) requires 97 RON, and Jap-spec imports are even fussier.

Not only is the article giving out bad advice - it completely misses the point of having a high performance car. WHY run it on a fuel that doesn't allow it to reach its potential, except in an emergency? Last time I used 95 RON in my PPP-equipped MY00, the engine felt asthmatic and wheezy, and it took a couple of tankfuls of Optimax before it was well again. What a waste, to make a habit of that

A.

davyboy

Mine runs on 95 RON

chrisp

Funny because I thought 944s were built to run on 4 Star (which was 98 RON) ?

davyboy

Mine says "unleaded only" on the dasj, and in the filler cap, says 95 unleaded.

I use better fuel for trackdays.

chrisp

Yep of course I forgot yours is one of the later 944s, my mates 1983 says 98 RON in his book. I told him to run on optimax and avoid that LRP stuff, seems to run fine on optimax.

dba

technically right or not,its hardly an urban myth and the word *nonsense* was mildy supercilious,its not totally nonsense.He deserves to be bombarded with emails.

bug-eyed wonder

Run it on diesel for all I care!
I'm sure mine runs better on SUL than NUL,didn't need some newspaper article or those on here to tell me that!
As has already been said the UKs will run on NUL but WHY when you're not getting the best from them?

AndyC_772

iTrader: (2)

Actually a completely standard UK turbo is reasonably happy on 95 RON; in this case it might be worth saving a few quid. Some companies that issue employees with fuel cards have a 'no SUL' policy, so those people may have a good reason to run on NUL if the alternative is to pay for the fuel out of their own pockets.

That said, my company hasn't noticed the difference over 45,000 miles

A.

pcdude

i tried 97 ron in my scoob and it missed and pinked ,,,,,,,, so went back to 95

chrisp

Yep put in what you want NUL or SUL its your engine . You can lead a horse to water but you cant make it drink .

Anyone reading this thread now has the opinions it up to you what you do, but no way any of the low spec 95 juice is hitting my fuel tank .

stephen30

I put optimax in mine most of the time. It runs more smoothly and IMHO picks up better. The small price difference on a tank is more or less made up for by the better mileage I get. Car is a Sport too.

Steve

steve G MAN

id like to put optimax in mine but cant find anywere in abingdon who sells it ill be damed if im going out of town to find the stuff lol its been ok on tescos unleaded

Claudius

Any modern Japanese engine will have a knock detector that will retard the ignition in order to allow for lower quality fuel to be used. So yes, the guy is right. However, the lower octane and CFV fuel will not give the optimum performance.

siwrx

uhm well i experienced this knock detectors ignition retarding, it was just like boost cut, the cars revs dropped to 0 as soon as it hit 5k, id hardly call that safe to run around in

dingy

PMSL - How come all these standard Scoob's blow up when people run NUL then.....

Claudius

Because of the anti pollution laws and the need for the manufacturer to keep the emissions low: AFR are very lean below 4500 rpms, quite rich (to compensate) above 4500 rpms. That's also why people who never really hammer the car and rev it hgh break more engines than the nutters!

Mudchuka

My95 had been run on 95ron most its life 89000, i then swopped to super and found it was sharper and did more to the gallon(still not alot but better)then try optimax but not impressed maybe expecting to much

RB5320

I ran my first MY99 on NUL only. No problems at all. The warning on the fillercap (to use SUL only) supposedly relates to countries where the octane level is lower than here.
Now run my RB5 WR on SUL whenever possible. The PPP certificate states that the car is designed to run on SUL, but that NUL will do no harm - you may notice a drop in performance (something along those lines as I dont have it with me)
So I would say it is ok to run UK cars on 95 octane, but better to use SUL. In any case, the RB5 is more economical on SUL which negates the extra cost per litre.
Obviously I am only talking about UK cars here.

Steve

si325i

use optimax 98.6 RON. more mpg, faster, works out cheaper.

Diablo

My late model UK Integra handbook stated that anything less than 97 RON should NOT be used except in emergencies.

On 95 it was noticably noisier, rougher and didn't like to rev (presumably due to the ECU compensating)

Hardly an urban myth then

There are a number of cases of the Integra and Accord type R's (UK cars) suffering excessively noisy engines (replaced under warranty) which was put down to using 95 Ron for long periods.

FFS - would you be happy running to 8900 rpm on 95 ron?

Frankel writes for Autocar IIRC. And how much innacurate cr&p does that magazine put to print.......

D

pcdude

i read this item in a canadian car mag whilst on holiday ,

The nature of a higher octane fuel is to cause a much more powerful explosion in the combustion chamber this in turn puts greater strain on the engine , however most performance cars that use high octane fuels have the engine replaced after a very short period of time and therefore does not affect the engine over a long period .

Now im thinking higher octane over a long period , all those big powerful explosion smashing down on the pistons , crank and valves ?
its got to make the engine work harder , or it wouldnt perform better would it

(flame suit on lmao )

Diablo

Sorry, but that is complete rubbish

VERY simply put RON is a measure of a fuel's ability to withstand pre ignition. Higher RON allows higher compression/more boost and/or more ignition advance without the fuel igniting before it is supposed to leading to detonation which may cause damage.

Higher compression/boost and/or more ignition advance is what will mage for a bigger/more efficient "bang" and that is what gives more power - not the octane rating.

Its a known fact that 95 ron causes many UK scoobs to det (UKtype 22B, STI7) to name a couple and so to say the long term use of 95 causes no damage is utter rubbish.

D

pcdude

mod
before you start saying ppl are talking rubbish,, go to this site and READ 1st and make sure you have the facts 1st

http://www2.shell.com/

it reads to me " eariler combustion transfer maximum energy to the piston , the crankshft and road wheels " , therefore more power/energy is applied to the piston , crankshaft , = working harder ,,,,

ppl who make statesments without facts ,,,,,,,,,DOH