Standard, Super or VMax Unleaded

[S99]

This has probably been covered to death already but I'm new to Porsche ownership so please be patient with me.

I've been told conflicting info on what a Boxster S can run on. The manual and filler cap says 98 RON, some people say Super (eg Tesco 97 RON) is fine, whereas others say ordinary unleaded works just as well.

Any advice / experience would be most welcome.

[Fidgits]

i dont know about the Boxster, but my 996 has the 98 RON on the fuel flap.

Now, this is obviously what Porsche reccomend you run the car on.

Standard super Unleaded is 97RON, Shell Optimax is 98 and Tesco Super is actually 99 RON.

I think most people go for Optimax/Ultimate, I personally use the Tesco 99 RON as it is close to where I live.


If you read the manual, there may be a comment (there is in mine) that if you do run it on 95RON (standard unleaded) then the ECU will retard the timing to suit, but then, thats a bit like ordering a vindaloo and asking for it not to be too spicy

[nbetts]

Fidgits said:

i dont know about the Boxster, but my 996 has the 98 RON on the fuel flap.

Now, this is obviously what Porsche reccomend you run the car on.

Standard super Unleaded is 97RON, Shell Optimax is 98 and Tesco Super is actually 99 RON.

I think most people go for Optimax/Ultimate, I personally use the Tesco 99 RON as it is close to where I live.


If you read the manual, there may be a comment (there is in mine) that if you do run it on 95RON (standard unleaded) then the ECU will retard the timing to suit, but then, thats a bit like ordering a vindaloo and asking for it not to be too spicy

I thought the Optimax/VPower stuff is now 99? I know it used to be 98...

Anyway, I run mine on either BP Super (97) or Tesco Super (99) they are the two closest suppliers of fuel where I live. You can run on regular unleaded with no bad effects but the car will be a little slower and it will consume more fuel.

Enjoy...!

[Fidgits]

nbetts said:

Fidgits said:

i dont know about the Boxster, but my 996 has the 98 RON on the fuel flap.

Now, this is obviously what Porsche reccomend you run the car on.

Standard super Unleaded is 97RON, Shell Optimax is 98 and Tesco Super is actually 99 RON.

I think most people go for Optimax/Ultimate, I personally use the Tesco 99 RON as it is close to where I live.


If you read the manual, there may be a comment (there is in mine) that if you do run it on 95RON (standard unleaded) then the ECU will retard the timing to suit, but then, thats a bit like ordering a vindaloo and asking for it not to be too spicy

I thought the Optimax/VPower stuff is now 99? I know it used to be 98...

Anyway, I run mine on either BP Super (97) or Tesco Super (99) they are the two closest suppliers of fuel where I live. You can run on regular unleaded with no bad effects but the car will be a little slower and it will consume more fuel.

Enjoy...!

yes sorry, I forgot V-power was now 99, I thought optimax was 98?

[baptistsan]

Good timing. Took the car out this weekend and had the exact same thought. She has always been filled with V-power, but got stuck Saturday so put Total Excellium (97 RON) in. Performance wise, no difference from the Shell stuff, but it seems better mpg. Will try a couple more tanks and see how it goes.

[rimmer]

go for shell optimax/bp ultimate or tesco 99

[hutchingsp]

Have to admit I'm back on "do I really need Optimax" mode with the recent petrol price increases.

I know all the "you can afford a Porsche" side of things but it's still 8p a litre.

[noumenon]

I've only had my 986 S for a few weeks. During that time, I've run a tank of 95 RON BP and a tank of Tesco 99. Tesco winds hands down. It feels much smoother, probably as the car is not constantly retarding the timing. From now on it's Optimax or Tesco 99 all the way. No contest.

[MikeP1]

'scuse my ignorance but would these comments apply to a 993 ?

[diesel130]

hutchingsp said:

Have to admit I'm back on "do I really need Optimax" mode with the recent petrol price increases.

I know all the "you can afford a Porsche" side of things but it's still 8p a litre.

I haven't put anything but V-power in mine, but when I did some checks a few years back on std unleaded vs Optimax on my Celica GT4, I got about 10% more mpg with Optimax, effetively offsetting the increase in cost per litre.

[noumenon]

diesel130 said:

I haven't put anything but V-power in mine, but when I did some checks a few years back on std unleaded vs Optimax on my Celica GT4, I got about 10% more mpg with Optimax, effetively offsetting the increase in cost per litre.

I found the same in the past too. Even though the car had more primitive management (no knock sensor). I guess more power means less throttle opening which in turn means more mpg.

MikeP1 said:

'scuse my ignorance but would these comments apply to a 993 ?

Yes, though not I suspect as much as the boxster since the engine management will be more primitive.

It's also worth noting that higher ron fuel adds knock protection. So I'd far rather be running a boxster with no knock, than using 95 and having it knock and retard. OK, I don't expect it to let go, but all knock is bad knock (aka detontion).

[SNDa]

does the whole tesco fuel issue / risk from a few months ago not apply to their 99 RON fuel? I haven't been back since.

Edited by SNDa on Monday 30th April 17:26

[noumenon]

That could have happened to any of the retailers. The fuel all comes from tanks in a small handful of refineries. Given the risk of another stuff up, they'll be on red alert, so probably the safest at the moment!

I am suspicious of normal 95 ron supermarket fuel as the additives package may not be as good. However if you read their web info, the tesco 99 has a better additive package.

www.greenergy.com/products/99_octane.html

Edited by noumenon on Tuesday 1st May 12:48

[SNDa]

thanks philip.

[egbert]

rimmer said:

go for shell optimax/bp ultimate or tesco 99

agreed

[S99]

Tesco 99 sounds just the ticket, however can anyone advise which Tesco forecourts in the Teesside area stock 99 RON as I've only seen 97 RON.

[Vesuvius 996]

noumenon said:

That could have happened to any of the retailers. The fuel all comes from tanks in a small handful of refineries. Given the risk of another stuff up, they'll be on red alert, so probably the safest at the moment!

I am suspicious of normal 95 ron supermarket fuel as the additives package may not be as good. However if you read their web info, the tesco 99 has a better additive package.

www.greenergy.com/products/99_octane.html

Edited by noumenon on Tuesday 1st May 12:48

I worry about this bioethanol. It rots fuel lines if it's too strong.

[noumenon]

Good point, reading up, it is more acidic and only safe in small proportions. I suspect we'll start to see it in more fuels. It can be cheaper than using petrol, as well as an octane booster. The UK's target of 5% of transport fuels from renewable sources by 2010 will also put pressure on the oil refineries/retailers. It's probably the case that there's not enough research out there over large enough samples and long term.

Mmmmm. Well I'd rather my boxster wasn't a guinea pig, so perhaps I'll stick to optimax for now.

[noumenon]

Newsflash:

Shell V-Power now replaces Optimx which was developed with Ferrari, working alongside their Formula One Team, and with a main focus on responsiveness and track reliability. This improved formula features higher octane (99 RON).

[MauriceC2S]

MikeP1 said:

'scuse my ignorance but would these comments apply to a 993 ?

Absolutely ! Knock detection will be active on 95 RON, reduce your 993s performance to Smart car levels ..

cheers, Maurice