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I just asked the question. coz my car had a label of unleaded. not sure what rating it was.

Plus i have read somewhere that E85 mixture is ok for the car too.

But i do agree with people here. i get more mileage on my cars when its on 98ron. runs better goes longer.

According to the FSM, the ECU switches to a 'knock map' when it detects knocking. But I have never observed it or tried to trigger it.

Yes, but there seems to be this perception that the ECU "removes" timing when it detects knock on the fly.

I've never seen any evidence of it, when I played around with Uprev and set the knock map up, it is quite simply just another Ign timing table to set say 20 points lower than the standard table.

I just asked the question. coz my car had a label of unleaded. not sure what rating it was.

Plus i have read somewhere that E85 mixture is ok for the car too.

But i do agree with people here. i get more mileage on my cars when its on 98ron. runs better goes longer.

E85 requires a custom dyno tune, complete with a marginally larger set of injectors.

As above, you CANNOT dump a tank in and expect the car to run ok.

  • Like 1

Plus i have read somewhere that E85 mixture is ok for the car too.

Yeah good luck with all that.

Its amazing what other kids can tell you in the sand pit these days

Edited by Howaitonaito

sometimes its just good to know...hehe Thanks for the info guys!!!

fyi: my 350GT has never tasted petrol below 98ron in my care.

E85 requires a custom dyno tune, complete with a marginally larger set of injectors.

As above, you CANNOT dump a tank in and expect the car to run ok.

Yeah good luck with all that.

Its amazing what other kids can tell you in the sand pit these days

Yes, but there seems to be this perception that the ECU "removes" timing when it detects knock on the fly.

I've never seen any evidence of it, when I played around with Uprev and set the knock map up, it is quite simply just another Ign timing table to set say 20 points lower than the standard table.

Yes, i believe that is correct, it is just a 2nd map with a fairly heavy timing retard (and fuel mix richen).

The FSM specifically says the knock sensor is a 'last resort safety device' and is not a tuning device, so when knock occurs the ECU just smashes back the timing to try to prevent damage, it was not intended to 'adjust' to low octane fuels.

And the other false perception is the ECU uses the knock sensor to advance the timing for higher octane fuels.

the only ECU I know that actually uses multiple knock sensors to 'tune' the timing is the newer WRX STI ECU.

Well the article i read was from cars guide and not specifically talking bout our skylines but were talking about modern cars. Im guess anything over year 2000 is a modern car.

That is why there are forums like this to ask questions and get answers from experienced owners.

Thanks for your statement though.

:)

If that place you read that awesome piece of factual *cough* information also said the the boogie man exists would you believe them.

No.

Has anyone used e10 91 on their v35s?

Our cars can use 91ron but not sure if with E10 would work.

read me

http://www.unitedpetroleum.com.au/united/fuel/unleaded-e10

do a little homework ,...e10 is 95 octane...i dont know why the misconception I hear so often, I guess because its cheap eveyone thinks its low octane...Its 95 octane at cheaper cost....and yes it should be fine to run...run it in my 04 honda all the time...may get 50kms less a tank but at least i know my injectors are clean...

No way is e85 ok for your car.

some cars with high compression rates can run it ok., I know guys in USA have tested it in Hondas and it runs good and pulls harder faster than petrol.....

that said

Its still not a very good idea but if it were an emergency you can get away with it

You would be surprised how much e85 you can put in the tank before the ecu calls it quits and throws a code. Remember the o2 sensors in these modern cars are very good at re-calculating short term fuel trims. I have heard 50% is usually ok.

You would be surprised how much e85 you can put in the tank before the ecu calls it quits and throws a code. Remember the o2 sensors in these modern cars are very good at re-calculating short term fuel trims. I have heard 50% is usually ok.

But they run to AFR... Not lambda.

E85 and 98 have different stoich ratios. Which the O2 sensor can't take into account. It's fixed on 14.7- petrol.

Both have a lambda of 1 ( lambda is just the indication of the best or most efficient ratio). So you might then tune petrol to 11.5afr, however that isn't equal to the same ratio when using e85

As the sensor reads lambda it automatically compensates for different fuels. I tune e85 to 14.7:1 on my gauge and it is just as stoich as a petrol tune. (just remember, e85 isn't 100% ethanol anyway.)

United 100 octane is garbage. its not really 100octane since it uses 10% e10 to boost the octane rating. been using it until i got my car uprev tuned and now running shell 98, much better

you are a moron. octane is octane. it's a way of measuring any fuel. LPG has an octane rating too. E85 is ~105-110 octane depending on the exact blend.

United's E100 works really well. In my R33 it was noticeably better than 98RON.

Yeh, it's 100 octane ;) lol

I get poor economy using it compared to normal 98ron fuel.

Up to 50% worse km per litre (ie 250kms for 60L of United 100 compared to ~370kms with Mobil 98)

50% worse? It's either your right foot or something is seriously out of whack with your car. I ran United E100 all the time and it made almost no difference to my fuel usage.

E85 and 98 have different stoich ratios. Which the O2 sensor can't take into account. It's fixed on 14.7- petrol.

Both have a lambda of 1 ( lambda is just the indication of the best or most efficient ratio). So you might then tune petrol to 11.5afr, however that isn't equal to the same ratio when using e85

O2 sensors work by sensing lambda, not AFR. They measure the ratio of oxygen in the exhaust gas to oxygen in the air, and their output changes around lambda 1 regardless of fuel. The O2 sensor doesn't know you've squirted 14.7:1 worth of fuel into the motor, it doesn't care. All it cares about is how much oxygen is left in the exhaust gases and that is lambda.

  • Like 1

Ok, so let me try to understand this.

Hypothetically, you can fill up your stock as a rock car with e85, drive it around on closed loop, and have a e85 lambda of 1?

What is the e85 afr equilivent of 14.7?

No, because the stock ecu will only add or subtract around 10% of the fuel. Anything outside that range will trigger the MIL as the ecu will know something is seriously wrong.

Ethanol stoich is 9:1 I think. Not sure what e85 would be as I have never needed to know.

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