95 or 97/98 octane

[legg360]

Is there any noticeable difference between 95 and 97/98 on performance and fuel economy for a non mapped mk6 GTI, I guess if mapped with that fuel in it would make a difference but does the standard map recognise the different fuel and give more power because of it or does it just lighten your wallet to help you go quicker 

[tweed]

I always said it was bullsh!t.  But.....It does make a difference on high bhp/turbo engines.
My car has a sticker on the fuel gauge saying 98 ron. (M3) so if the germans say to use it, then you use it.
I fill up with the shell nitro plus. And the car does not like normal unleaded!

Also I will add I use shell nitro plus for the kart racing. One day shell was sold out so we got normal unleaded and we did notice a difference too. Didnt pull so well bottom end and we had to gi e it some more teeth on the rear sprocket.

However I doubt you will get more mpg. Well if you do it still costs more for the fuel so works out the same.
Personly its just a slight power increase.

I think its about 5 to 7 bhp from tesco unleaded to shell nitro+

[legg360]

Yea I can see why your M3 doesn't like 95 fuel, ive seen maps that say must be run on 97/98 fuel, and if I had one of those maps I would, but if the car is on the standard map and designed to run on 95 I wonder if there is any difference there.

[Nino]

Honestly in my car gti 150 turbo. I use tesco momemterm and . Get about an extra 20-30 miles a tank from it.

[tweed]

Honestly in my car gti 150 turbo. I use tesco momemterm and . Get about an extra 20-30 miles a tank from it.

Yes but how much more does it cost to fill up?

[Seanl]

Same as mentioned in tweeds reply, my Corrado states to use 98 ron and its for a reason. I filled with standard unleaded when I first got the car, and it didn't like it at all. I've since used either shell v-power nitro+ or Tesco momentum and there is a noticeable difference. Around town you won't gain any mpg, but on a run the extra cost is offset by the slightly better mpg.

[Wazzzer]

It's also a lot better with turbo charged cars for reducing knock

[mcgee9t2]

as said, better for detonation and less liable to premature ignition etc.

will proberbly see about 1bhp more on a non mapped turbo car, and will be slightly better for the engine.

for me I use 95 seems to run fine, every so oftern I use a few tanks of 98 to give her a treat, but my car is unmapped so don't really see the point in 98, plus the amount of miles I do I couldn't be botherd to pay to constantly use higher ron fuels, however when it comes to map time I will be using higher ron fuels for around 3 weeks to make sure that I have a good quality high octane fuel in the tank and then will be using higher ron fuels.

[Wazzzer]

good call mate, you'll need it in there a fair bit of time before you get it mapped so the ECU can adapt to the higher octane

[thai-wronghorse]

It certainly made a difference when used in my chipped ABF. If i used low RON or cheap supermarket fuel for extended periods I'd occasionally get pinking at low revs under load. A tank of super would always resolve it though.