I would personnally say if you are running less that 260 BHP try AT-YOUR-OWN-RISK! (not mine) running your impreza on 95RON, my WRX has been running on it for 2 years without any trouble (28,000 miles), except for 2 months were I tried it on 98RON and it made bugger all difference going from 95 to 98 and then back to 95. No loss in power (boost gauge reads steady 0.85Bar), no knock, and MPG is still the same.

The RON rating is to do with the latent heat of detonation or something, which means that 95 RON will self detonate at a lower cylinder temperature and lower compression than 98 RON and this is what gives knock (and why some use water spray). But if your engine doesn't get too hot (flat out everywhere and high revs all the time) then the onset of knock should be less.

Well that's my theory anyway.........

Tizard99.

 

Looking for a Scoob at the mo, and would prefer to buy the WRX based on interior, spec, power etc.

The insurance is much higher which I could shop around for, but my problem is SUL, and the fact that it is not available near where I live

Is there really that much difference between 95 RON and 97 RON? What happens if you run the WRX on normal unleaded 95?

DW

 

Detonation! Thats what happens.
It might depend on how tuned the car is, some standard ones have been run on 95RON, i think.

Octane booster would have to be used for peace of mind, i think the price of a tank of UL & booster is not far off a tank of SUL, although prices change, i could be wrong.

There is also 'stuff' like Broquets, ive no experience of this though.

There was a post in the drivetrain section i think, about an STI that runs on 92RON. Theres some good info on there.

What WRX are you buying?

Phil.

 

My 95 STI 2 was detonating on unleaded95.
Runs alot better on SUL. You could buy a box of octane booster and add that to UL, some people on here do that. I run mine on Millers octane and SUL for max smiles.
The reasons you give for buying a WRX are the same as mine were 15 months ago, I havent looked back.
Try the below ins companies, I'm with Keith Michaels.
Andyp

Crowethorne Insurance 01344 771626
Torview insurance services 0181669888
Bell Direct 0800 140180
Hyperformance 0181 9393944 contacts: Mark or Wilf
Admiral 0800 600800
Footman James 0121 651 6250
Kieth micheals ins plc 0181 288 0081 contact: Jeremy
O.P.I 0870 242 0800
Adrian Flux 01553 777888
Priviledge 0113 292 5555
Coversure Ins 01480 412494
J.D.I Insurance 01189 502155
Academy 0800 731 4984
Greenlight 01277 263030
Schofield’s contact Tom (Rum on BBS

 

Hi M8, spoiler looks wicked now it's fitted. Anyway, my 93 WRX was running on 95ron when I bought it and I used it on that for the first few months until I was told about possible probs (didn't make any difference though). I may be wrong but the older cars suffer less due to a bigger turbo/lower compression (but a bit more turbo lag) Anyway, Check around your local garages as I found most of them didn't advertise SUL on there price boards but did have a pump or two with it in Sainsbury's is one of them. also try BP, Esso and shell.

Let us know how you get on or if you want any help

Charlie H

 

my93 wrx- originally ran on 95, six months later det problems!!! switched to sul with broquets and no probs since. I prefer the peace of mind and not having to shell out for a new engine rather than saving 5p a litre. pumpers.

 

Here's a pic of the inside of my petrol flap (sad i know!!)



Note the label 'Nisseki DASHRACER 100 '

I believe this is a brand name for some 100RON fuel, sounds much better than ' Super Green ' and the like..

Needless to say mine doesn't like 95RON.

Phil.

 

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:<HR>Originally posted by tizard99:
<B>I would personnally say if you are running less that 260 BHP try AT-YOUR-OWN-RISK! (not mine) running your impreza on 95RON, my WRX has been running on it for 2 years without any trouble (28,000 miles), except for 2 months were I tried it on 98RON and it made bugger all difference going from 95 to 98 and then back to 95.
Tizard99.[/quote]

Did you reset the ECU when you changed to 98RON? If not, that's why you didn't notice any difference. The ECU map would have been full of previous det episodes, so would have retarded the ignition timing to counteract this. One tankful of SUL would not have altered this. I am presuming that you have a pre-99 WRX which had the learn-very-slowly ECUs.

D.

 

Cheers everyone.

Clarey - nothing specific at the moment but went to look at a UK MY95 and wasn't keen - the Corolla interior is very naff

Charlie - Glad to hear the spoiler looks good, no probs fitting it then?

DW