Currently running my 02 STi Type UK on 95 as dealer said it was fine and usually just use that for commuting to work and back when not 'playing'.

However today was 'playday'

Car seemed fast as normal even though weathers been really hot up here today.

Anyway, on a dual carriage way a car came up behind me while i was in the outside line behind another car and was tailgating. Once the car in front pulled in a dropped into 5th and floored it to get away....it stayed with me. Got held up again so dropped into 4th this time, pulled away very very slightly maybe 1-2 car lengths if that.

Car in question was a brand new C5 (not sure what model). Mines standard. Acceleration took place above 70ish

Would 97 fuel make THAT much difference?
Just wondering realy because its a little annoying when a C5 can just about keep up on straight road with lot less power?

 

Just to add, followed a P1 a week or so ago and we kept accelerating hard on occasions and even with my knackered clutch (now replaced) could just about keep up. So dont think its running badly.

 

You will find on the sti it states 98ron minimum to be used on the inside of the fuel flap and in the hand book.I have run mine on 95 in an emergency and its like driving a different car.The other thing is if your switcing between 95 & 97/8 the ecu is always having to re-learn,So your never really getting the max benifit from the 97/8 when you use it.

 

I questioned this with the dealer about the sticker on the fuelcap stating the recommend RON and he assured me that the sticker was put on all EU cars but Type UK cars could ignore this and run 95 quite happily. I am bloody annoyed if this is true as i would of ran it on 97+ all the time.

Only reason for using 95 was i was told it was fine and its all thats available on my route to work. Guess i'll start using 97 or more from now on.

Does it make that much difference though? Power comes in at 3.5k with a good kick in the backside but then seems to drop a little power but still pulls well all the way.

 

I think thats not true, I believe the wrx says 95min on the fuel flap.My uk2000turbo certainly did.That was a classic shape my2000 though.
Someone with a wrx will come along and let you know soon

 

The sticker on the fuel cap of mine doesnt state an actual RON but something like 'Premium RON Minimum'. I can check in the morning as i cant remember exactly.

Definitely going to use 97+ from now on. Can i just pull the fuse on the ECU or does a dealer need to reset it properly?

 

The ecu will re-learn fairly quickly,No need to do anything just try to use the same fuel all the time.(97/98)

 

Not quite true, it states on the inside of patrol cap super unleaded(irish turbo)
now super unleaded was 97 octane over here(alas no longer available) so putting 95 into the sti is asking for trouble. It can take the ecu 2 tanks or more to "learn" about the new fuel, and changing back and forth is NOT recommended.

Stick to optimax 98 ron and is good for the engine

all this from experience ..

 

So if youre using, say optimax, in between small spells of regular unleaded in a uk classic turbo, would there be no percieved benefit from the optimax?

 

My classic UK 99MY says super unleaded only inside the fuel cap !

However, the owners manual says 95 RON will be fine.

I do however run it on super unleaded though, as super is pretty cheap near me at 86.9/l

 

I'v got a 53 wrx and on the fuel flap it does say 98 only

 

if you run your car on 95 ron the ecu retards the ignition etc causing a power loss so the engine can operate safely without any knocking my 03 sti says 97 ron minimum so with optimax you will reach engine's full power ie 265bhp safely and more smoothly,a dealer can do reset for you and should not charge you unless your dealer is a bit tight
martin

 

Your STi isnt the worlds quickest motorway car im afraid to say. There are a lot of rep mobiles out there which will scare you.

Gary

 

but a C5? Looking at the stats on them not even the V6 is close and this was an estate which was 4 up, i was 3 up.

 

Damn, the fuel cap sticker does say something like premium RON and Super 98 RON recommended. Its not in english so not sure what is says after the Premium writing.

Last time i trust what a dealer tells me and that was an actual Mechanic i spoke to!

Stuck some Optimax in (never used it before) and although there was still some 95 stuff in after a few miles i could feel the difference already. Boosts coming in fully around 3.5k and holds where as before it seemed to ease off around 4.5k.

Few more tanks and it should be sorted. Cheers!

 

Even the wifes smart roadster which is 800cc turbo has to be run on optimax,why would u run your scoob on anything but the best fuel u can get your hands on.

 

you should be able to leave pretty much anything for dead in an STi, must be the fuel if you have nothing wrong with the car

 

you should have been in 3rd!

 

I suppose whether you need to worry depends precisely which model of C5 it actually was.

Was it one of these:
http://www.canadiandriver.com/articl...03corvette.htm

or one of these:
http://www.magic-malini.de/images/Sinclair_Foto.jpg

 

3rd would of put the revs around to 6-7k so would of had to change to 4th immediately

Seems fine now with Optimax in. Should be even better once its done a few more tanks on the stuff.

ricardo: lmao! I wish it was the first one
Done a search and this was it

 

Well that may have given you a bit of a scare ..... But our thoughts are to that person who can drive something so hideous !!

 

 

Are u saw u did not have your handbrake on. I could pull away from one of them on my push bike

 

so apart from all the small talk!!!!!!!! can you or should you flitter between 95 and 98 only because the nearest garage that sells 98 from me is about 10 mile away??????????

 

I say NO you shouldnt Unless its an emergency,Stick with 98 all the time

 

I get Optimax as often as I can, and on the one occaision that my wife decide to put 95 RON in it I could tell the difference immediately. She thought I was sad to even notice, but it was like driving a Kangaroo the pick-up was so bad.

 

errr no actually. A 2.0 or 2.5 ltr rep mobile will not be far behind on a motorway. Dont get caught up in the hype that you drive something which nothing can touch, it can and it will. Especially on motorways.

Gary

 

Very true, found it theres a v6 version as well!

Anyway happened to come across another one today although it was on a nice quiet B road heading hoe and he was in front giving it some but braking like hell for every corner. Overtook easily on a nice long straight and noticed it was an unmarked mountain rescue car. I slowed down for the villages etc with him tailgating me. I started getting paranoid that he was following me home so pulled a good lead and parked out of sight in the yard. Min or so later he went past and with another 5 mins so does a rescue defender, about 3 police cars, dog section van others. lol The road he followed me up was a 3 mile dead end single track country lane so u can understand i thought i was being followed for some daft reason.

Later got a knock on the door from a copper and found out some kid had gone missing after a party lastnight and they are worried as this is out in the sticks near a reservoir and moorland and they are from Scotland so dont know the are. Not the best of places to go walking at night when drunk

Cars definitely much happier on Optimax though and will be run on it or 97 al the time!!

 

if you are off boost and a big diesel is in his torque range or v6 is accelerating i just let them pass-then you look too cool to race and do not fet embarrased
martin

 

Then of course there is the fact that some of these big old barges are limited to 155mph. With my reckoning that means the driver can have a 3 minute wait every hour till we catch up in our scoobs. Shall I start talking about fuel stops now

Gary