Rolling Road last night.

Originally Posted by ukoldschool

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I take it your car has its standard ECU replaced with a MOTEC then? because the standard GTA ECU's fuel setting cannot be changed.

which is why its not worth spending money on increased RON fuel, unless you have shares in BP/Shell etc no matter what anyone tells you - you are wasting your time on an Alfa.

Some cars from outside the EU (mainly Japan) have ECU's that can adapt, but not the ECU in a GTA

With any ECU if you can alter the ignition timing you can map for 98RON. When someone says that a car is mapped for 98RON this mean that it runs quiet advanced ignition timing. If anyone claims that they can remap the GTA ECU but they cannot alter the ignition timing then they are lying. If you run an old engine with dizzy cap you can map it to run 98RON by increasing the timing advance manually by rotating the distributor.

Originally Posted by ukoldschool

yes, but they say that to cover their back witht he extra ron acting as a resistance against potential knock where theyve moved the ignition points about.
They reccomend it not because it will provide any extra power by using it, but if you dont your car may suffer reduced performance, or actually die

But the remap/chip does provide extra power..

Where do you think that power comes from? It can only be from either retarding (EDIT: advancing?) the ignition, or leaning off the mixture, both of which provide more power, but both also make a fuel more likely to knock.. So to prevent that, 98 octane is recommended. If you got a remap and used 95, it might be OK, but then the engine gets a bit warm and starts knocking, the knock sensor tells the ECU to bring the ignition points back down and you are effectively then running minus your remap. If you didn't have a knock sensor then yeah, the timing would stay at the "remapped" levels and it would knock itself to death.

I'm still trying to work out why the other 3.2's have 240PS, let alone this remapping business. Take the GT, physically identical to the 147 from intake all the way up to the last two bits of the exhaust. The 156 GTA differs more with different intake feed, manifolds, cats, as well as centre section and back box

Wonder what my 93,500 mile GTA is making, still seems to go like stink!

Just to ask a stupid question,
do you think that people might forget the climate on when they dynotest? This will absorb a good 10hp.

Don't know where UK is coming from here.
I would have thought it was beyond argument that loads of tuners can map the GTA to take advantage of 98.
Most of these remaps then require use of 98 due to the advanced timing, whats the issue?

Going a bit further : As it was explained too me by Jano, even the standard GTA ECU settings have a very modest "table window" of ignition timing advancement allowed.
This window can be reprogrammed as part of a remap so that you can have a map that will take more significant advantage of higher octane fuel by changing the timing and using the knock sensors to detect the current effective octane rating.

He offered me a map for my car, giving me the choice of either "require 98" or "allow use of 95 octane but detect and use higher octane to some extent (but lower than the previous option)".
My car is supercharged so its easy enough to detect the higher octane rating through the seat of your pants even though it accepts 95 octane, sensitive buttocks are probably needed for N/A cars I suppose but even a difficult to detect 2% improvement is useful for trackdays or the like. Not to mention the engine safety factor under extended extreme load.

Yup, notice how quick a car can feel on a cold winters morn!

Maybe im stupid aswell following trailbrakers explanation.

TB, right on the head!!

Sorry if im reading this late in the day but it seems my standard car is no better off on 97/98/100 ron fuel than 95 for performance??? Is this correct?

Sorry to be deviating from the original post by the way....

because, yours runs the standard ecu with the standard map, wont make any real diff when you pop 97/98 in, but we are talking about GTAs that the "map" has been optimised to run 98 RON

Thanks