Which octane rating for Legacy?

[Guest]

Hey - I've just bought a Subaru Legacy TS-R (1994) for driving around NZ - I'm in NZ for a year checking out this fine country.

Back home in the UK, I've always driven relatively low powered cars (1200cc) and so always put the lowest octane rating fuel in the car.

I've heard that with a car like a Legacy, you need to put a higher grade of petrol in it, for example at least 95/96 as opposed to 91 RON.

With the Legacy, should I always go for the highest grade possible? I see 98 RON is only available at a limited number of gas stations, whereas 95 or 96 seems to be quite readily available.

Another question, the lad I bought it from seems to have run the car on 91 for the last 20,000km. Will this cause any problems? The car's done about 185,000km in total.

Thanks

[DRFVDR]

95 or greater

being run on 91 should not make any difference,reset ECU and drive it with the right fuel in it

[Guest]

 DRFVDR said:

95 or greater

being run on 91 should not make any difference,reset ECU and drive it with the right fuel in it

Thanks for the quick reply.

Just out of interest, why would I need to reset the ECU?

And having never reset an ECU before, I googled how to do it, is the following correct?

 

Disconnect the Battery

Hit the brake pedal once disconnect for approx 30 seconds to run the entire charge out of the system.

Give in 30 mins if you can, then reconnect and you will be all good.

[WRXONP]

91 octane should be fine in a non turbo...98 in a turbo

the reason for resetting the cu is because subarus use electronic ignition timing (u cannot adjust it)...

resseting the ecu adjusts the timing to suit the fuel u are running

[GravelBen]

My old '97 TSR was certainly much happier on 95/98, though not as fuel-sensitive as a turbo. More economical on the better fuel too.

Resetting the ECU just helps it adjust to the higher octane fuel more quickly.

[DK]

I run my BH GTB on shell 95 as unfortunatly theres not 98 available near where i live however the car runs much nicer on 98, nz needs to sort it out.

[Pappu1]

Maybe test km done On different fuels and see what suits u best

[Guest]

 DK said:

I run my BH GTB on shell 95 as unfortunatly theres not 98 available near where i live however the car runs much nicer on 98, nz needs to sort it out.

I agree, I can only get 95 in new plymouth. In Wellington i used 98 and i wanted to test the difference in the fuels. I noticed the 98 is much better above 5,000rpm.

[WRXONP]

well on my old rex i dyno ran my car on 95 V-Power and it detonated like shit...ran it on 98 from gull and detonated like shit (ethonol blend) and then ran it on BP 98 and detonation on the knock link was minimal nearly disapeared...reseeting ecu each time too......

[matariki_gt]

 WRXONP said:

91 octane should be fine in a non turbo...98 in a turbo

the reason for resetting the cu is because subarus use electronic ignition timing (u cannot adjust it)...

resseting the ecu adjusts the timing to suit the fuel u are running

interesting

[subieboy]

 DRFVDR said:

95 or greater

being run on 91 should not make any difference,reset ECU and drive it with the right fuel in it

I agree

Have seen most non turbos run on 91 with no issues

[Guest]

all EJ engine apart from EJ15 are spe'd to run high octane fuel

EJ20 na can handle lower octane but can give issues with retarding timing due to det

EJ25 na must run 95+ octane - major power loss issue's at the best of times with these - let alone putting 91 in them

And oviously ALL turbo to run high octane fuel