What fuel do you use in your Z4 ?

[Colin_S]

Hi,

I've been using the super unleaded fuel in my Z4 2.5 for a little while, as it has a higher octane level than the normal stuff. A friend who has a vintage MX-5 suggested that I should be using something even higher octane like Shell V-Power or similar.

So I was wondering, what do you all use in yours ?

 

[Unitedleeds1919]

I Always try for super unleaded I often use the posh diesel in my van as well, I find it smoother and slightly better mileage that makes it very similar in cost by the time you have paid more but got further, just work out the difference in cost it’s not that much and maybe it’s a mind thing but it feels better

 

[Pondrew]

I always, always use petrol. I find it the best for any Z4.

 

[Rockhopper]

I use the Cheapest stuff Tesco sell. Pointless spending money on “high octane” fuels unless your car has been modified to make use of it. Super fuels may have other benefits but rather have the extra cash in my pocket.

 

[Gwest44]

The manual recommends 98RON but where not available says a minimum of 95RON can be used - so I generally stick to Tesco and use their Momentum which is 99RON

 

[Mike6]

I avoid supermarket petrol as there have been previous threads on this or at least only use it on occasion. Supermarket petrol doesn't have the additives or cleaning properties of say shell or Esso.
I vary usage between E5 and E10 for balance. I also use a does of redex now and then to keep the system clean.

 

[Pondrew]

Supermarket petrol doesn't have the additives or cleaning properties of say shell or Esso.

I would be very interested to see proof of that. Sounds like "car forum folklore" to me. :?

 

[pvr]

98 only, seen too many engine lights come on after a dose of 95

 

[Mr Tidy]

BMW recommend a minimum of 98 RON whenever possible for the N52 engines in E85/86s (and both my cars) so I always try to stick to Tesco Momentum, Shell V-Power or Esso Synergy Supreme as they are all 99 RON and E5. Most other "Supers" seem to only be 97 RON, albeit still E5. If I get stuck I have used them, but try to keep to a 50/50 mix with 99 so it should be 98!

Interestingly although Esso has always labelled theirs as E5 until a year or so ago it was actually E0 in most parts of the UK. At the time someone I know who volunteers at Brooklands said they tested a sample of Tesco Momentum and it was also E0 which suggests maybe they get their fuel from Esso.

 

[enuff_zed]

The DME adjusts over use. If you jump between one and the other it can never get a true reading.
I have used standard supermarket fuel in my daily 2.2 for nearly two years now with no issues whatsoever. The DME has had plenty of time to adapt and is quite happy on it.
Same would apply if you used exclusively 98 or above, albeit with a potentially improved performance,
The biggest issue is jumping about from one to another so the DME never has time to establish a datum.

 

[Zedebee]

The sticker inside my (M54) filler flap says 91-98 RON and it is happy on regular unleaded. 91 does not exist in the UK, but I understand is “Regular” gasoline in the US. Old fashioned, normally aspirated lumps like the M54 should be absolutely fine on regular unleaded (c.95 RON in UK) and the DME is clever enough to self-adjust in the 91-98 range. More modern turbo or high compression engines are likely to require a higher minimum RON.

 

[j3nks79]

As above the timing can advance to run up to 98ron.
I always use super as the cheaper E10 uses 10% ethanol which isn’t good for lines pipes injectors seals etc.
Rots the fuel system from inside out

 

[Gebbly]

Shell is my closest petrol station. For my last 3 cars (M135i, 330e, Z4M) I have stuck to v-power as much as possible. Sometimes I use Esso Synergy supreme when there isnt a shell anywhere nearby. If neither are nearby the missus knows our day trip/holiday will be taking a detour to find one

 

[darich]

Super unleaded whenever I can. But only because it has less ethanol and the car may sit for a while.
Not for any performance cleaning issues. I've used supermarket fuel in multiple cars and motorbikes for decades and never had an issue.

 

[DaveP]

Supermarket petrol doesn't have the additives or cleaning properties of say shell or Esso.

I would be very interested to see proof of that. Sounds like "car forum folklore" to me. :?

Indeed. I used to track a highly tuned, supercharged car on supermarket 97RON without a single issue. I currently track my 3.0i M54 on 95RON without a single issue.

The amount of enthusiasts who are sucked in by petrol company marketing is incredible.

 

[DaveP]

For anyone with an M54-engined car, I posted a bit of fag packet analysis of my experience with E10/95 and E5/Super on the Facebook group recently.

A precis would be that I did two days of trackdaying on the Ring, the first day with 95 and the second with Super (because I was in a rush and it was the only free pump). Looking back at my datalogging, I could see zero discernible difference in performance between the two days.

I'll be sticking with 95 in future, even on track.

 

[RAYK47]

I usually use E5. Not because of increased power or MPG. I had heard that it contains better additives that look after your engine slightly better i.e. cleaning agents etc.

I have no first hand experience or knowledge if this is true or not and it could have come from a fuel company as far as I know. But my theory is, it can't do any harm so why not?

 

[DaveP]

I usually use E5. Not because of increased power or MPG. I had heard that it contains better additives that look after your engine slightly better i.e. cleaning agents etc.

I have no first hand experience or knowledge if this is true or not and it could have come from a fuel company as far as I know. But my theory is, it can't do any harm so why not?

Yeah, that's not true.

 

[Pondrew]

But my theory is, it can't do any harm so why not?

It harms your bank balance over time.

 

[RAYK47]

Yeah, that's not true.

I expected as much but as I said I had no knowledge myself.

It harms your bank balance over time.

Yes I expect so :lol: