Porsche Enthusiasts Club Forum

Hi Guys,

What are the benefits/risks in using Super Unleaded in my S4 auto?
(I haven't put any in yet...)

Cheers,
Willber

Probably none, you may if your very lucky feel a very slight improvment in its running, The only thing that you will feel for sure is the is the lightening of your wallet

Hi

Not sure what you mean by "Super Unleaded" ??

If you mean VPOWER ...all 928s should use it as its 98 octane (you should have a sticker inside your fuel flap saying so)

All the best Brett

no risk I shouldnt think

98 octane every time! Incidentally my 83 S ran incredibly different on super whereas my 91 GT felt the same regardless of the fuel.

Mine ran a little better with Shell VPower which I think is 99 ron??

Varies by model year but in my 88 S4 the sticker on fuel flap is for 95 RON i.e. regular unleaded. The S4 also has knock sensors so will just retard timing if you try to use lower octane fuel than this.

Have seen some vague comments that the cleaning agents used in Optimax are a nice occasional treat for engine, but will make no difference to performance directly.

Thanks for all your comments. Sorry for the long delay, 2 weeks without a laptop.

My filler cap and handbook specify 95 RON so I'll stick to that unless anyone alse has other opinions.

Cheers,
Willber

Right, I've had a few weeks to try some things and am pretty sure that my engine runs better with 98-99 RON. I've tried to be objective (although this is not really possible without some blind tests) and engine smoothness and responsiveness seem to be improved over a number of different driving and weather conditions. Not sure about consumption as my driving habits are erratic wrt journey length.

I'm going to keep using it - I hope nothing breaks!

Cheers,
Willber

it will be fine. I ran some racing fuel in mine a little while ago and all was well.

There was a topgear or fifth gear scientific test using different fuels and then running on a dyno and the 99 ron definitely gave an inprovement.