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Moderators: IMOC Moderators, IMOC Committee Members
russo wrote:Have owned an MR2 turbo now for 3 years.![]()
Just read a thread which suggested turbos MUST be fed with superunleaded petrol.
![]()
Is this correct or not?
bri0905 wrote:Shell have been selling 98ron fuel for years.Was called optimax then got re branded to V Power.
Not sure when it became available but i've used it since about 2000.
reecep wrote:sorry for hijacking but Tesco Super unleaded is that the 99ron version or is that 97ron and there is another type that is 99ron.just asking as i keep hearing about it but all the Tesco's near me are labelled Super Unleaded 97??
allan welsh wrote:reecep wrote:sorry for hijacking but Tesco Super unleaded is that the 99ron version or is that 97ron and there is another type that is 99ron.just asking as i keep hearing about it but all the Tesco's near me are labelled Super Unleaded 97??
not all Tesco's supply 99, hence the 97 stuff.
seems they sell it everywhere but Leicestershire d'oh!!
boosch wrote:and Cornwall! its not even on their list of counties!![]()
I asked God for a bike, but I know God doesn't work that way.So I stole a bike and asked for forgiveness.
russo wrote:Have owned an MR2 turbo now for 3 years.![]()
Just read a thread which suggested turbos MUST be fed with superunleaded petrol.
![]()
Is this correct or not?
Jim Galbally wrote:AFAIK the MR2 ECU does not have active knock control so running it on xxxx fuel will normally end in distaster.
Jim Galbally wrote:thats not how active knock control works.
there will be a knock sensor which is a crude mechanical device that detects certain frequencies, these will be the frequencies that occur most during det.firstly, these sensors aren't great, no knock sensor is 100% reliable.
anyway, depending on the ECU, when the ECU detects knock it will do one of 2 things, the least common is enter LOS(limited operational strategy) aka safe mode/limp home mode.
very few ECUs do this, none i kow of on performance turbo cars.
the most common is it will retard the ignition timing until knock no longer occurs.
few things to take note of
*at the best of times this method is unreliable
*at the worse it just doesnt work
*if the ECU doesnt have it in the first place
(which i dont THINK rev1/2 does) it's totally irrelevant
Jim Galbally wrote:thats not how active knock control works.
there will be a knock sensor which is a crude mechanical device that detects certain frequencies, these will be the frequencies that occur most during det.firstly, these sensors aren't great, no knock sensor is 100% reliable.
anyway, depending on the ECU, when the ECU detects knock it will do one of 2 things, the least common is enter LOS(limited operational strategy) aka safe mode/limp home mode.
very few ECUs do this, none i kow of on performance turbo cars.
the most common is it will retard the ignition timing until knock no longer occurs.
few things to take note of
*at the best of times this method is unreliable
*at the worse it just doesnt work
*if the ECU doesnt have it in the first place
(which i dont THINK rev1/2 does) it's totally irrelevant