Tesco Super 99 or 97 Octane

[pigapumbu]

Originally Posted by bobcat

I can answer that, but would really need to hear why its considered a must on an engine that can vary timing and fueling.

Hi Bob,

I am still waiting to hear what a 97RON can or can't do for a car thats been modified. As far as I am aware, its good to use a higher RON which is mostly to deal with detonation. The language as told to me years back is that the internal engine has hot spots and cheap quality fuel or in this case, lower RON are prone to igniting before the spark goes (full compression). So to prevent this, a higher RON is used which helps. My thinking and correct me if I am wrong since I am in no way technical but curious, for cars that have been modified and trying to squeeze the last bhp out of it (within parameters of not causing a blowup), one should then use a higher octane. Something Georgey Dee mentioned.

By giving the car engine the "right" juice the ECU learns, then adjusts ignition etc to maximise what it is being fed. Give it crap, BHP is down as ECU has to readjust to what it has to work with. Thats my take on it I would like to know more if I am mistaken. Please do explain further why you claim what georgey Dee wrote is wrong .. all of it.

cheers.

Originally Posted by bobcat

well for one the ecu wont lean out the fueling when running higher octane fuel, meaning you need to get a remap to raise the fuel pressure!!!

you use less fuel because you can run more ignition advance (higher cyl pressure thus more efficiency) and thus get more torque from the same amount of fuel and air, which means the ecu can inject less fuel for the same torque as before.

thats the advantage of higher octane fuel.

I must be missing something here. You say, ECU won't lean out the fueling yet a paragraph down say, ECu can inject LESS fuel for same torque because of higher RON.

Sounds like a different way of saying the same thing George penned down.

"As for a standard car,,,,, well the ECU does 'learn' what fuel your using, thats why some companies claim that you use less fuel on super therfore saving money,,,,HHMMM.

Your T5 will after 10 miles of driving learn that super is in it and wind off the fuel... The difference being that if you need more it's there in the form of increased octane."

Awaiting your explanation on this. Thanks

cheer

[Georgey dee]

I would always put 97 and above in a modded car. The ECU can only vary fuel so far than It cuts the ignition to protect the engine. If you run a higher octane the ECU can cope better with the Mods.

That's the best way I can put it without causing an argument.

[Steve940estate]

I have filled the tank on my 940 with Vpower on the odd occasion that I am near a Shell garage and have noticed a difference.

Normally it gets Tesco's or BP but with the Shell it's is a lot smoother and idles slower. I guess the engine runs cleaner with the Shell petrol in it and the management doesn't have to compensate by increasing the revs.

Shame about the price though.

[davev70]

i take it that we should all use v-power in our volvos then i do and wont use anyother it doesnt run the same without it.

[Viper_7]

Originally Posted by davev70

i take it that we should all use v-power in our volvos then i do and wont use anyother it doesnt run the same without it.

Yes it's one of the best fuels out there. Sure it costs more but c'mon it's only like a quid or so extra a tank. Drop in the ocean. Compared to the better return and less likely to have problems.


It's all a con though - our cars will run on water really.

Vipes

[bobcat]

Originally Posted by pigapumbu

Hi Bob,

I am still waiting to hear what a 97RON can or can't do for a car thats been modified. As far as I am aware, its good to use a higher RON which is mostly to deal with detonation. The language as told to me years back is that the internal engine has hot spots and cheap quality fuel or in this case, lower RON are prone to igniting before the spark goes (full compression). So to prevent this, a higher RON is used which helps. My thinking and correct me if I am wrong since I am in no way technical but curious, for cars that have been modified and trying to squeeze the last bhp out of it (within parameters of not causing a blowup), one should then use a higher octane. Something Georgey Dee mentioned.

By giving the car engine the "right" juice the ECU learns, then adjusts ignition etc to maximise what it is being fed. Give it crap, BHP is down as ECU has to readjust to what it has to work with. Thats my take on it I would like to know more if I am mistaken. Please do explain further why you claim what georgey Dee wrote is wrong .. all of it.

cheers.



I must be missing something here. You say, ECU won't lean out the fueling yet a paragraph down say, ECu can inject LESS fuel for same torque because of higher RON.

Sounds like a different way of saying the same thing George penned down.

"As for a standard car,,,,, well the ECU does 'learn' what fuel your using, thats why some companies claim that you use less fuel on super therfore saving money,,,,HHMMM.

Your T5 will after 10 miles of driving learn that super is in it and wind off the fuel... The difference being that if you need more it's there in the form of increased octane."

Awaiting your explanation on this. Thanks

cheer

the ecu wont lean out the fueling thats the point, you get more torque from less air and fuel (thus the same fueling) from greater ignition advance.

for an extreme example of how ignition timing affects torque read up on how antilag works.

higher octance fuel allows higher cyl pressure, thats all!!!!!!!!!!!!!!!!!!!!!

[bobcat]

[QUOTE=Georgey dee;276932]I would always put 97 and above in a modded car. The ECU can only vary fuel so far than It cuts the ignition to protect the engine. If you run a higher octane the ECU can cope better with the Mods.
QUOTE]

the ecu can only vary fueling so much???

how much fuel do think the engine uses on idle compared to when on WOT?

[CTCNetwork]

Hi,

Just an interesting side note for you peeps here..

In Germany and Sweden the "regular" unleaded is 91 RON..
Super is our regular 95 RON..
And as for Shell V-Power is (in Germany at least) 100 RON...
Yummy stuff!!!

Des. . .

[Velorum]

Originally Posted by CTCNetwork

And as for Shell V-Power is (in Germany at least) 100 RON...
Yummy stuff!!!

Des. . .

Guess that youve been using some of this over the past few days Des!

Hope you enjoyed your trip (and a real bummer I had to go to Manchester instead!)

I guess the only way any of us will catch up on your posting total is if you go away for 18 months.

Good to have you back!

[cumbrianmale]

Originally Posted by Viper_7

Yes it's one of the best fuels out there. Sure it costs more but c'mon it's only like a quid or so extra a tank. Drop in the ocean. Compared to the better return and less likely to have problems.

Vipes

Deffo a cracking fuel the 960 loves it but my wallet doesn't. The price differential is always 7p/l so between £3.50 and £5.00 a fill up for me, as usually between 50 - 70 litres depending if I fill at 1/4 tank or under.

A bottle of redex is £3.50 for 2 doses. So I am giving this a try.