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Vs Ecotech 3.08

sapeter

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so in overall responses some are saying 98 Unlead is better but dearer in price where Unlead 91 is cheaper in price but low on Km's
and performance and Unlead 95 pricey but reasonable in performance..

Is that what everyone is saying? I need to be very sure on this change. Also is it wise to put like Unlead 91 or Unlead 98 straight into tank with a
quarter of tank of unlead 95 in it at moment ????
 

Brett_jjj

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The engine management system in these vehicles constantly adjusts the ignition timing to suit engine load, throttle position, ambient air temp, octane rating of the fuel used etc etc. . The engine can take full advantage of any higher octane fuels if used.. The ECU continually monitors the engine for pinging/knocking/detonation via the knock sensors, and if it detects any, it will pull ignition timing out until the pinging/knocking stops.. Usually the higher the octane rating of the fuel, the more ignition timing can be used before detonation/pinging/knocking occurs under power/load. The more timing advance you can run, (to a point), the more efficiently the engine will run, which means better economy, more power, and cleaner emissions and better fuel economy.
To see just how much difference the engine management makes to these engines, You only have to look at the engine bay of a VL commodore and compare it to a VN, the VL has hundreds of pollution pipes etc running all over the place, whereas the VN has bugger all pollution systems, this is all because of the engine management system, which controls the engine parameters way more finely, which in turn, greatly drops the emission levels and increases the engines efficiency etc, so theres no need for all the pollution gear like on the older models.
A tune on these vehicles will basically give the ECU access to higher ignition timing values..
With my VS V6 I used to get excellent fuel economy just with the standard tune and running 98 octane fuel, but over the last couple of years Ive done a hell 0f a lot of experimenting with different timing values in the tune and I have got the fuel economy down even more, around 6 litres/100km highway, and around 8-11 litres/100 km around town. Thats on 98 fuel, and driving fairly normally. The tune hasnt made the engine more powerful as such, but its definitely a lot more responsive than before, especially noticable when accelerating from light to mid throttle.
 
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sapeter

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Brett you still didnt answer my question... lol

Also is it wise to put like Unlead 91 or Unlead 98 straight into tank with a
quarter of tank of unlead 95 in it at moment ????
 

DrZ

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Brett you still didnt answer my question... lol

Also is it wise to put like Unlead 91 or Unlead 98 straight into tank with a
quarter of tank of unlead 95 in it at moment ????

Yes its safe, its not like your car can only read 91 95 or 98, you would get a mixture somewhere between 95 and 98. Your car will measure the octane, and then run the timing accordingly.
 

DrZ

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Unless you are getting your car tuned, if this is the case I would recomend ensuring your only running the octane you want to run, ie run your tank to empty fill with octane you want, run to empty fill.. an you should be sweet. :D
 

sapeter

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Yes its safe, its not like your car can only read 91 95 or 98, you would get a mixture somewhere between 95 and 98. Your car will measure the octane, and then run the timing accordingly.

thanks for the info DrZ, appreciate that....
 

kingswood country

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The engine management system in these vehicles constantly adjusts the ignition timing to suit engine load, throttle position, ambient air temp, octane rating of the fuel used etc etc. . The engine can take full advantage of any higher octane fuels if used.. The ECU continually monitors the engine for pinging/knocking/detonation via the knock sensors, and if it detects any, it will pull ignition timing out until the pinging/knocking stops.. Usually the higher the octane rating of the fuel, the more ignition timing can be used before detonation/pinging/knocking occurs under power/load. The more timing advance you can run, (to a point), the more efficiently the engine will run, which means better economy, more power, and cleaner emissions and better fuel economy.
To see just how much difference the engine management makes to these engines, You only have to look at the engine bay of a VL commodore and compare it to a VN, the VL has hundreds of pollution pipes etc running all over the place, whereas the VN has bugger all pollution systems, this is all because of the engine management system, which controls the engine parameters way more finely, which in turn, greatly drops the emission levels and increases the engines efficiency etc, so theres no need for all the pollution gear like on the older models.
A tune on these vehicles will basically give the ECU access to higher ignition timing values..
With my VS V6 I used to get excellent fuel economy just with the standard tune and running 98 octane fuel, but over the last couple of years Ive done a hell 0f a lot of experimenting with different timing values in the tune and I have got the fuel economy down even more, around 6 litres/100km highway, and around 8-11 litres/100 km around town. Thats on 98 fuel, and driving fairly normally. The tune hasnt made the engine more powerful as such, but its definitely a lot more responsive than before, especially noticable when accelerating from light to mid throttle.

A more technical view of what I was saying basically, I'd like to know what your doing, I'm toying with the idea of a tune on the Eco just for the economy side of things while retaining the power it has.

But yes, all three, 81 95 and 98 you can run, e10 if you like, though not recommended! The higher octane fuels are more expensive at the pump, but in the real world where your getting extra out of your tank, it works out to be cheaper, and as said above, cleaner too, to be honest, I'm not even sure why fuel companies bother with the lower Ron fuels!


Taking donations of cash, card or full frontal nudity.
 

AlexVSII

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I could understand 95 octane being of benefit to a VS but I doubt 98 would be of much, at least running the stock tune given 98 octane only became available in this country in the year 2000.

So I can expect to see power, responsiveness and economy benefits from switching to 95 octane fuel? I have up until now been using regular 91 but a recent move has meant that this fuel is a lot harder to source than when I was living "in the bush"

Brett, do you make your custom tunes available to other people or is it just something you do for personal use? I wouldn't mind a tune that gives fuel mileage of around 11 l/100km in realistic conditions while not sacrificing power. Not to mention 6 l/100km on the open road beats someone I know who drives a Honda Civic...
 

VS-S

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Sure 98 is better, but I noticed when I used 98 a couple of times (I always run 91) that it doesn't fire up as quickly. Is that just mine or does anyone else's have the same problem?
 
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