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NogaroDrew

Octane Boost

As you cannot get anything apart from 95 RON in Ireland where I'm going home for my holidays, can anyone recommend a good quality octane booster easily available?  
autogear

millers cvl turbo used it regular
http://www.millersoils.co.uk/auto...gmentID=232&sector=Motorsport
NogaroDrew

autogear wrote:
millers cvl turbo used it regular
http://www.millersoils.co.uk/auto...gmentID=232&sector=Motorsport


Thanks mate. Any idea where I'd get some?
autogear

halfords or most car parts shops that stock the millers products
Aragorn

If its mapped properly, just put 95 in and drive it. It wont cause a problem.

Only a complete cowboy would tune a car in such a way that the ECU was unable to compensate for having to run on 95 octane fuel.
aidank1981

Aragorn wrote:
If its mapped properly, just put 95 in and drive it. It wont cause a problem.

Only a complete cowboy would tune a car in such a way that the ECU was unable to compensate for having to run on 95 octane fuel.


this! mine is mapped by AmD and i always run it on super unleaded when i'm down on the mainland and 95 Ron when i'm home (no other choice)

i believe it recalculates every time its started so in the unusual instance you didn't stop you engine while refuelling make sure you do when changing fuel!

you will notice a drop in performance!   i miss super unleaded....
Noggymike

I use it on "The Run" just as a safeguard when we hit "no man's land petrol stations"
ruxy

Just put the 95 in
Jism

Even on 95, you can get very nice torq figures if mapped properly. The difference with 95, 98 and 102 micht be up to 5 to 20 hp. Do you really need 20hp extra on top of the 380hp stock?
Mocke

Jism wrote:
Even on 95, you can get very nice torq figures if mapped properly. The difference with 95, 98 and 102 micht be up to 5 to 20 hp. Do you really need 20hp extra on top of the 380hp stock?



This is not correct.
Difference between 95 and 102 would be closer to 100hp on a high power car.
It is not to be compared.
95 is really bad fuel.
Use higher always if you can.
Jism

Hmmmm...

https://www.youtube.com/watch?v=WTaBngvsPrc

https://www.youtube.com/watch?v=gQghB4asSnI

And

https://www.youtube.com/results?search_query=premium+fuel+test

Hows that for 100HP ? We're talking about a S4 / RS4 B5, not a super duper yet car.
Mocke

Yes
We are talking S/RS and i have tuned few of those in range
500 - 800+ bhp

Those videos you are posting clearly shows that you are misunderstanding things.
Just using higher octane fuel will obviously not net you huge gains - it will some thoe.
It needs to be custom tuned for specific fuel octan.
Gains are huge this way - the proper way.
RoGEK

Mine was mapped by MRC on RON102 / Aral 102 because I live really close to the german border (5km).

FYI, my S4 made 360PS+ and 560NM+ with only decat (xs-power) downpipes and stock cat-back without any other mods done.

Fuel will make a difference when mapped to it !
Aragorn

The simple fact is any car mapped in the UK, should be able to run on any UK fuel. The ECU has plenty adaptions built in to allow it to adjust for fuel grade. If its been tuned in such a way that it cant adapt, then its badly tuned. (and yes, i'm sure someone can find some extreme edge cases were this isnt true, but for the vast majority of cars it will be)

Some factory tuned VAG cars (and i imagine others too) do fairly interesting things on low octane fuel, like they'll increase the boost pressure to compensate for the retarded timing, which means when tested back to back as per your videos above, the difference will be minimal.

Obviously once aftermarket tuned theres less scope to do clever stuff like that, because everything has been pushed to the limits, but its still perfectly possible to tune the car in a way that if its run on lower octane fuel it'll safely turn itself down a bit and ensure its not going to explode.
Jism

Yeah but those special tunes, are usually for racing purposes, and not daily use. I think that is the main problem, you can tune it all you want but want to keep the daily thing in it.
RoGEK

In my opinion car should be tuned on the fuel you're always using..

If that would be ron95.. then map it at that.....

Like I said, mine is mapped at 102... just because i'm normally using 102 and the car is no daily driver.. just for fun.
Otherwise mapping to 98 would be better imho.

I've planned to go to LeMans next year... So I got the same problem.
Max you can get in France is RON98...  I'll take a few bottles of octane booster with me... just to be sure.
It will run on 98... it is safe... but it something between the ears
Jism

The torque figures for a S4 / RS4 B5 with 95 can be pretty good actually. You are missing the high-end HP's these engines produce but i'm sure with almost 500 to 600nm your car is fast enough already for daily use.

Mine is mapped for 98, but i can pour in 95 as well. It's just more sensitive for knocking and if i push it the car simply holds in (retarding of timing).

It's not like your going to miss those 10 to 20HP extra.
RoGEK

Jism wrote:
.

It's not like your going to miss those 10 to 20HP extra.


Compared to the numbers our dutch praised "expert tuners" get, it would be an almost 40PS and 70NM difference.. I think you def. will notice it.
Mocke

Aragorn wrote:
The simple fact is any car mapped in the UK, should be able to run on any UK fuel. The ECU has plenty adaptions built in to allow it to adjust for fuel grade. If its been tuned in such a way that it cant adapt, then its badly tuned. (and yes, i'm sure someone can find some extreme edge cases were this isnt true, but for the vast majority of cars it will be)

Some factory tuned VAG cars (and i imagine others too) do fairly interesting things on low octane fuel, like they'll increase the boost pressure to compensate for the retarded timing, which means when tested back to back as per your videos above, the difference will be minimal.

Obviously once aftermarket tuned theres less scope to do clever stuff like that, because everything has been pushed to the limits, but its still perfectly possible to tune the car in a way that if its run on lower octane fuel it'll safely turn itself down a bit and ensure its not going to explode.



The car will obviously run both on 95 and 102.
There is no function  in Me7x that considers diff  octans. It will only retard timing.
If mapped to its full potential on 102 - trust me the car would not run long before burning pistons if pushed on 95.
The other way around- you would be leaving a lot on the table.
Infact - no tuned car should be running on 95.
At least 98.
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