Ok guys I know we've debated this before and I know what it says on the inside of the petrol cap 98 Ron on sti wrx is 95

My question is I'm thinking of trading in my wrx-s in for an sti but I'm against having to add 98 all the time, so do any of you who run the new sti n 330 use 95 for that motorway drive, this week I've done 700 miles so as you'll understand not financially viable to be running an sti with 98 for what I do but I wanted to ask if anybody does it, no lectures lol

On that note I've also asked 2 garages Subaru one about the 98 and what it does and would it void warranty no it doesn't void it at all and neither have they had any in that had blown or come in shagged due to wrong fuel. Buttttt it does state it on the cap for a reason

Just annoys me guy at works got a knew focus rs and had the 400bhp conversion also so kits now a 400. R and he doesn't have this fuel ****e issue

Bah

Cheers

 

i bought a 54 wrx sti a few months ago and thought ***k it i am gonna stick with cheap stuff, but then got the lectures you refer to from others> i thought right i will now try the best stuff. Like you i do about 600 to 1000 a week every week. Anyway i must say i didn't notice anything better with miles, performance etc,but i did notice that every now and then when i could't get to a good petrol station i would put £20 of cheap stuff in and i kid you not within 50 or so miles engine light would come on. Fill up 2 times after that and the ght would go off. Now i know people are probably thinking what a load of crap, but i am telling the truth. Now i just make sure good stuff only!

Rob

 

I guess there has been huge debates over this as i have been in a few on other forums haha.

my basic view is Subaru state it for a reason, on a Uk model it should be ok as they will be mapped with English unleaded but the JDM models get mapped with much higher octane fuel so might be more of an issue.

the main problem is that with lower octane it wont be as stable and will be more likely to det... that will kill the engine.

if in doubt get the car remapped and that will sort any issues out as the guy mapping will be able to take into account the octane rating and pull the timing so that it doesn't have any dire effects

 

i think you should ask the question of why you would want to buy an sti in the first place to put 700 miles a week on it.surely you would be better off if you do that kind of milage,to buy the sti and have a cheaper more economical car for work that costs less on fuel.so that way you can put the proper fuel in the sti and not risk damaging it,keep milage to a minimum,and save yourself cash on fuel through the week with the second car.

 

If your trading in a WRX-S which can't be more than 18 month's old, for an STI the loss on the WRX-S must be huge then buying the STI, & your worried over a few pence a litre.
Put the fuel the STI was designed for in, you will pay in the long run, the piston,s are fragile enough without pushing your luck.

Has the Focus got 400 bhp on 95ron i very much doubt it.

 

Loss isnt that much, i have a friend he will me a good price, think on his floor he is selling them for 18k i know he wont make much on me, so yeah possibly a loss but not as great as i once thought. But then again he has STI on 08 n 58s for 18.5 and 19.5 also, so there an even bigger loss for the STIs

As for ths focus your prob right it wont be 95ron, but as he said when i asked him he DOESNT have to use 98 if he dont want, he can use 95 although power will be affected it wont hurt it, maybe remapped dunno.

But i agree i may look at summat else, or even get a diesal for day to day running, but i do make a wee bit in the fuel i get 21p a mile on a 500 mile journey i make around 15quid, and before anybody says running costs i dont look at them just Gallons only.

On my insignia i had for 6 months i lost money only 11p a mile

 

Wrxd is what you want then
I get 45 mpg prob nearer 50 if you did longer journeys rather then quick blasts

 

i bought a corsa diesel for work. saves me about £60 per week. and put the 99 ron in my scoob. my mate put 65000 miles on his scoob on 95 ron with no problems so far.

 

hi
i have an 04 sti which i have mapped for 95 ron just done 100 miles on 20.00
thats 25mpg which aint bad.
i have 3 or 4 different maps on my laptop which i can switch at any time for max power 330/340 on v power ...but really didnt buy a scoob in the first place
for eco driving lol. for that get a diesel

 

with the history (well documented on here) of the hatch STI's being VERY sensitive to DET and thus munching pistons, I'd never advise anyone to run theirs on 95 RON....motorway driving or not...
Subaru will take the party line of denial..right up to the point of a claim...then you'll find out it was not advised and thus not covered.

If you do though...also invest in a knocklink..and watch the pretty lights (better than an 80's graphic equalizer)

 

I'll tell you something also - Subaru will advise you not to run it on 95 also.

I've had Subaru's for the past 12 years.
Best we get in N.Ireland is 97
Now before I actually bought the 330S I said to Prodrive that I don't have 98 available and would I be able to use 97 like all the other PPP'd cars I've had.
They said the car will run fine on 97, but not to put 95 in it.

Here's what I was specifically told.
"Super unleaded fuels can typically range from 97-99RON. Use of 97RON fuel should not in most normal operating conditions cause detonation significant enough to trigger a reduction in boost pressure, however the full performance potential may not be quite reached. Outside of a rolling road test the affect of using 97RON fuel would be very difficult for a driver to perceive."

 

Hi, We looked at buying a WRX s but got an STI in the end . Subaru's figures say that the STI is more economical and has lower emissions .
Martin

 

Martin Jefferys at The Engine Tuner showed me the map he did for mine. Good lord the standard map is just SO rich as it comes on boost it's unreal. No wonder economy is so poor on these things.

Frankly, I suspect Subaru expect us all to put 95crap in and put our foot down. The richness helps to hold the detonation until it can pull the timing forward.

Mine went from 276 to 309bhp just by leaning it. Economy was miles better too until I got home- the Island is horrible for economy as the only dual bit is up a steep hill!

I leave mine at home and drive a crappy taxi to work now! £1.49.9 last week too!!!