Pros & Cons of Z4 engine choices...

[sars]

The 2.5 Si in some ways is the best of both Worlds, cheaper car than the 3.0l but a significant improvement in performance over the 2.0l my only bugbear with that car was a resonance drone at 75 mph.

It's always better to have more power than you need than less power than you want, so get a 3.0l, drive it carefully on a motorway at 70 mph and you will get 37 to 38 mpg,

 

[lacroupade]

so get a 3.0l, drive it carefully on a motorway at 70 mph and you will get 37 to 38 mpg,

compared to 50mpg+ in my four-pot 8)

 

[Lillywhite]

My 2.0i Z4 returns a far better mpg than my 116i Series 1 hatchback.

 

[GaryH]

Good point whoever flagged up the running costs in terms of insurance, servicing etc etc.

Insurance on my 2.0 was just £40 a year more than a small Fiesta I owned previously!!! That was fully comp, protected with Admiral. Servicing costs are good, and I purchased a BMW warranty for £366 for the year! Cant argue with that!

All depends on your budget I guess, but for a good all rounder which wont break the bank then the 2.0 will meet your needs.

 

[inkey$]

All good advice in previous posts. Owned a 3.0 and had the best of everything depending on how you wanted to drive it. Re: the boxter Id think twice for two reasons. Firstly IMO the interior is god awful and secondly youll pay more on servicing the thing. The Zed is the dictionary definition of refined speed/cruise.

 

[dyshipfakta]

My opinion is if your going to own one then you may aswell not leave yourself wondering what if. Excluding the m of course get the 3 litre and have done with it .

 

[Stuart Truman]

Btw, I wanted to ask, can you use normal '95' unleaded, or is the 'super' variant recommended in a Z4?

normal 95 will do

if you don't mind pinking and knocking...

Tapatalking...

 

[lacroupade]

Btw, I wanted to ask, can you use normal '95' unleaded, or is the 'super' variant recommended in a Z4?

normal 95 will do

if you don't mind pinking and knocking...

Tapatalking...

But the knock sensor prevents any sign of pinking surely.....thats what its for!?

 

[GaryH]

I dont get any pinking or knocking using normal unleaded.....

 

[Stuart Truman]

Maybe in a standard car. Not sure on an //M. #69 doesn't like 97 RON, only happy on 99. She's a fussy tart

A knock sensor will cut in when knocking starts, so you'll still get some with cheap fuel.


Tapatalking...

 

[lacroupade]

Maybe in a standard car. Not sure on an //M. #69 doesn't like 97 RON, only happy on 99. She's a fussy tart

A knock sensor will cut in when knocking starts, so you'll still get some with cheap fuel.


Tapatalking...

Should be fine - the US Manuel for the M states it can run as low as 89AKI which is about 93RON, but that 91AKI (95RON) is the standard. You can't sell a car globally these days if it isn't happy to run on a pretty wide range of fuel.

And the AK sensor probably works faster than you can think, so I'm sorry but I just don't believe you would ever experience pinking in normal circumstances. The last time I drove a car that pinked was a side vale Ford Popular in about 1969....! And I strongly suspect most drivers under the age of about 35 don't even know what it is.

 

[GaryH]

I wouldnt want to put any cheap fuel in a 3.0 M - if you can afford to run that car you can afford the decent fuel lol!

Although my 2.0 runs ok on normal unleaded you do certainally notice the car running better on the posh stuff

 

[lacroupade]

I wouldnt want to put any cheap fuel in a 3.0 M - if you can afford to run that car you can afford the decent fuel lol!

Although my 2.0 runs ok on normal unleaded you do certainally notice the car running better on the posh stuff

Well as I say, the manual recommends standard 95RON even in the M.

And you're right about the 2.0, its all down to the knock sensor that allows the ignition, once the ECU has recognised theres a better quality fuel going in, to advance the ignition, otherwise the engine wouldn't be able to take advantage.

 

[Adamski]

My E46 3 series' manual said to run it on 98 RON. Havent looked at the zed's manual in that much detail, but assumed it was 98 as well. Never had issues on 95, but prefer using 97 or 99

 

[GaryH]

My manual for my 2.0 56 plate Z4 says to run it on 98 RON. Page 77 of the manual says:


"The engine has a knock control function, thus can run on different grades of fuel.

The engine of your BMW is designed to run on Super Plus petrol, octane number 98 RON. Fill up with this grade whenever possible ao that the nominal performance and fuel consumption values are achieved.

You can also run the engine on premium grade unleaded petrol octane number 95 RON.

The minimal permissable grade is regular grade unnleaded petrol, octane number 91 RON."

 

[Bing]

I think general consensus is that 95 is ok for all but the ///M and Alpina's, from what I have read on here. I used super for a number of weeks and the engine ran perhaps a bit more smoothly, but could have been my imagination... Didn't check the MPG because whilst mine is a daily driver it's a 3.0, I didn't buy it for any sort of practical reason whatsoever, and when I can I drive it in a manner that entertains the child in me :evil:

 

[lacroupade]

I think general consensus is that 95 is ok for all but the ///M and Alpina's, from what I have read on here. I used super for a number of weeks and the engine ran perhaps a bit more smoothly, but could have been my imagination... Didn't check the MPG because whilst mine is a daily driver it's a 3.0, I didn't buy it for any sort of practical reason whatsoever, and when I can I drive it in a manner that entertains the child in me :evil:

The 2006 M Owners manual - available on here - says:

Required fuel
Super Premium Gasoline/AKI 91
This gasoline is highly recommended. However,
you may also use gasoline with less AKI.
The minimum AKI Rating is 89.

In English money AKI 91 = 95RON

98RON (which would be about AKI 94) doesn't get a mench? Just saying.....