i have been using 98ron in my 3rd gen and had just learnt that unless i advance the timing then 98ron doesnt do anything.

now the question is. what does does it mean to advance the timing and how do you do it.

the engine management computer should be able to cope with the difference (self adjust)

reset comptuter or

if not
the dissy may have slide grove and nut that can be undone and with a timing light you can adjust the timing mark on the crankshaft pully to suit

the engine management computer should be able to cope with the difference (self adjust)

reset comptuter or

if not
the dissy may have slide grove and nut that can be undone and with a timing light you can adjust the timing mark on the crankshaft pully to suit
..............

Sports is or was running a little mod that will advance the timing. Otherwise a piggyback ECU of some sort will be needed.

That was fooling with the barometric pressure signal IIRC. The correct way to do it is with an intercept between the crank angle sensor and ECU.

Cheers
Heath Young

If you do do it, then make sure you always fill up with 98ron as the 3rd gens do not have
knock sensors to detect pinging if you accidentally filled it with 91ron fuel and damage will
occur.

yeh well thats why i wanted to do it. to make using 98ron not completely useless. lol.

spoke to a mate whos a mechanic and he reckons you cant get it done unless you get a piggy back ecu. something about how the fuel injection is set at different levels for each rpm at each percentage of your foot on acceleration, or something complicated like that.

would reseting the battery do anything?? or not.

think i might just drop down to 95ron, i know 95 wont make any difference to 91ron but for the $5 a tank i might as well chuck the healthier stuff in. and for no performance or economy difference i don't think i can justify 98.

and i dont think i can justify a piggy back ecu atm. maybe in the future but not yet.

It cant be done unless you have a piggyback ECU fitted.

Basically if the car doesn't have a knock sensor (which all 3rd gens DON'T) the timing cant be advanced by the computer. It needs the knock sensor to determine the octane of the fuel before it can advance the timing. What it does is keep advancing the ignition curve until it senses detonation then backs itself off slightly so it has maximum advance for that quality of fuel.

The 380 has one so it can benefit from the higher octane fuel but there is absolutely no power gain to be had from a 3rd gen with a standard ECU running 95 or 98 RON.

why did they do that?
whats the point of taking off a knock sensor.

oh well i have to fill up today so im just gonna drop it back down.

why did they do that?
whats the point of taking off a knock sensor.

oh well i have to fill up today so im just gonna drop it back down.

Probably just a cost saving measure. No knock sensor means only one fuel map is needed, saving a bit of cash in the development stage.

can be done without a piggy back computer, I did worked a treat. PM me if your interested

the only gain from running higher octane fuel is that it will burn slightly better, but not really any gains in power or economy.

higher octane fuels are actually harder to ignite than lower octane fuels.

Unless the engine is designed to run on a higher RON it will make little difference. there's more to it than advancing the timing, higher compression for one. RON is related to its resistance to knock thus bump up compression with Higher RON to extract all the extra energy contained in the Fuel.

Edit I'll try again
High Octane 98 gives greater resistance to detonation it has nothing to do with flammability rating.
By using 98 it allows an engine to utalise higher compression without knocking thus developing more power.
The make up of 98 fuels means they generally have more energy contained in them.

The average engine built for 91 will not have the compression to take advantage of the anti knock properties of 98 and winding up the timing does not change the compression which is where the power is developed.

I read up on this stuff recently after reading an article in wheels and wanting some facts to see if I was wasting money on 98.

hey sports, i looked up your mod that advances the timing. it technically isn't a timing mod. it bend the signal from the air flow meter to think it is in a lower load area of the mapping (which by coincidence has more advanced timing). as you are 'adjusting the timing' you are leaning out the AFRs at the same time. if it was a true timing mod then you would be able to advance the timing a lot more because it wouldn't be altering the AFRs.

you can buy piggy back units (the apexi SAFC and AFC) that will do the same thing as what you have done for around $200 second hand or $400 new, except they let you alter it in steps. on the old ones you can set it in 12 points across the map, and the new ones 16 points. you aren't just stuck to the one setting. also on cars with knock sensors you can view how much knock you are getting, as well as various other things, like afm voltage, correction %, rpm. and the greddy emanage ultimate has dropped in price heaps. you can pick them up new for just over $500 plus the cost of the harness, and they will let you control the timing seperate to the fuel (which can also be altered seperately to the timing), plus they have a built in launch control, you can have 2 seperate timing and fuel maps that can be changed at the flick of a switch, you can run the wideband o2 sensor through the emanage so it graphs the AFR along side rpm, and you can get rid of speed limiters too. i tuned one on my mates r33. they are very easy to use.

hey sports, i looked up your mod that advances the timing. it technically isn't a timing mod. it bend the signal from the air flow meter to think it is in a lower load area of the mapping (which by coincidence has more advanced timing). as you are 'adjusting the timing' you are leaning out the AFRs at the same time. if it was a true timing mod then you would be able to advance the timing a lot more because it wouldn't be altering the AFRs.

you can buy piggy back units (the apexi SAFC and AFC) that will do the same thing as what you have done for around $200 second hand or $400 new, except they let you alter it in steps. on the old ones you can set it in 12 points across the map, and the new ones 16 points. you aren't just stuck to the one setting. also on cars with knock sensors you can view how much knock you are getting, as well as various other things, like afm voltage, correction %, rpm. and the greddy emanage ultimate has dropped in price heaps. you can pick them up new for just over $500 plus the cost of the harness, and they will let you control the timing seperate to the fuel (which can also be altered seperately to the timing), plus they have a built in launch control, you can have 2 seperate timing and fuel maps that can be changed at the flick of a switch, you can run the wideband o2 sensor through the emanage so it graphs the AFR along side rpm, and you can get rid of speed limiters too. i tuned one on my mates r33. they are very easy to use.

Yep it advances the timing and leans off the fuel a bit, that's why you take it to a dyno mob and adjust it there so you can see the air/fuel ratios

or just find someone with a wideband o2 sensor kit.

or just find someone with a wideband o2 sensor kit.


Yeah but then your doing it illegally.

how do you figure that? you don't have to go over 100kmh. since you can't legally go over 100kmh anyway, why do you need it tuned for high revs in the higher gears?

how do you figure that? you don't have to go over 100kmh. since you can't legally go over 100kmh anyway, why do you need it tuned for high revs in the higher gears?

Pretty sure melb to syd is 130 all the way....

is it? i know that from cooroy to near brissy is 110kmh. but my point is that if you can't go over these speeds why do you need it tuned above them? unless you go to the track all the time? i have access to a wideband kit (as well as 2 dyno's, but that is beside the point). so i could just hook that up and go for a drive. and if i want more load on the motor i can just apply a bit of brake with my left foot.