I'm sorry if this has been done before on here, but what views do other vRS drivers have on super unleaded.

Personally I have used one full tank of 97 (not 98) and i did think the performance was better...more vicious acceleration...but I'm not sure if I was imagining it! Sainsburys in Coventry only charges a 1p premium so there it is worth it but else where it is much more expensive.

What do you think?

It depends what car it is in. All my cars run better on it, but they are highly tuned. It has been proved scientifically that 97 / 8 can give more power on some cars and not others. But feel is more subjective, so if you think it works then carry on. It must also be noted that the additives Shell use do help keep your engine tip top.

The higher the octane of the fuel the more the RS will perform.

The knock sensor can tell the RON of the fuel and adjust the engine management to give you more horses or not.

Personally i have started using Tesco 99 which comes very highly rated.

Run a couple of tanks of this through and the difference is very apparant.

The higher the octane of the fuel the more the RS will perform.

The knock sensor can tell the RON of the fuel and adjust the engine management to give you more horses or not.

Personally i have started using Tesco 99 which comes very highly rated.

Run a couple of tanks of this through and the difference is very apparant.

plus on regular fuel your bhp will be down be about 20 bhp plus

The FSI engines are intended to run on super unleaded. If you use 95 then as said you will lose power but also economy will be reduced. I expect you would find that the saving per litre achieved by running 95 would be negated by the poorer economy.

Agreed - I tried both during the free petrol period and preferred 97 [can't find any 98] and seems to give a few more mpg, though haven't measured it "scientifically".

Thanks for your replies (especially considering having looked through past threads I realise this HAS been done to death previously!)

I have decided to start using the dearer stuff for a couple of weeks and see if the economy improves.

Dan

higher octane is always best in the vRS

i don't think the car 'knows' that a higher octane fuel is used so advances timing and ups boost pressure and fueling to give you more power but in fact quite the opposite(at least in my car). if i have my boost controller set to max and run it on 95 then i get pinking so the knock sensor retards the ignition and drops the boost/fueling levels to save the engine from exploding.

higher Ron fuel isn't more potent but more stable at higher temps so can allow a car to run more aggressively in terms of timing/boost.

i think.

Octane is all about resistance to detonation under pressure. IIRC. And aren't FSi motors particularly high compression? I don't really know what I'm talking about, TBH...

I never really noticed a difference between 95 and 97/98 in my MkI. Never tried anything less than Optimax in the 2 fill-ups that my MkII has had as the emphasis on 98 seems more pronounced for this one.

Mine is mapped specifically to 98 ron, and on the occasions ive had to use 95, the differance in accelleration is quite noticable.

the difference in mine on 95 is virtually dangerous when it starts to pink :eek:

thats why i use nothing but super

And aren't FSi motors particularly high compression?.

The New Octavia vRS engine has a compression ratio of 10.5:1 whereas the original Octavia vRS is 9.5:1. The Octavia 1.4 (55KW), 1.6 (75KW) and 2.0 (85KW) engines are also all 10.5:1.

its a bugger to find round south shields..the nearest optimax I can find is at whitemare pool which means a round trip of about 8 miles just to fill up

I cant find anybody else selling a higher octane fuel round the town centre

The FSI engines are intended to run on super unleaded. If you use 95 then as said you will lose power but also economy will be reduced. I expect you would find that the saving per litre achieved by running 95 would be negated by the poorer economy.

I think this is a really good point, only had my 2.0 FSI for 3 weeks now, and run it on 95 but what I've read here and (even the manual) I'm gonna try 98 next... Using 95 is probably false economy!

I am getting my 1.6 Octy Tiptronic shortly, anyone out there with the experience of 95 vss 98 on this engine as I want to start on the best from the start

I am getting my 1.6 Octy Tiptronic shortly, anyone out there with the experience of 95 vss 98 on this engine as I want to start on the best from the start

dont bother spending extra for your 1.6...... you wont get any gains

save the money