Buying and "chipping" a Z4 18i

[Pond]

Hello,

I am seriously looking at buying a low mileage 2013 (ish) Z4 as a summer toy for SWMBO (and me), if Boris will let me!

I'm looking for an 18i M sport and having it remapped, as it would appear all 2.0 litre engines can achieve at least the power of a 28i with a £300 "chip".

My questions are: Are there any known issues to look for on a series 2 Z4 and has anyone remapped an 18i?

On paper, my favoured re-mapping bods are quoting 274bhp and 373NM, which is quite a hike over the standard 156bhp and 240NM.

Me being a cheapskate, or as I like to think wanting value for money, it seems a no-brainer to buy a cheaper 18 and get the power of a 28 for pennies. Am I missing something?

I'm not too concerned that the gearbox and clutch can take the extra oomph as will be looking for a manual anyway. I presume they are the same in all 2 litre engines!?

I have been checking the MOT history of all the cars I'm interested in (very useful tool, thanks gov.uk) and it would appear fragile alloys and uneven tyre wear seem the most common things I've seen.

Any advice or thoughts would be gratefully received

Stay safe, Andy

 

[andyglym]

Am I correct in saying that the 18i is normally aspirated? If so no way you'd get circa 120 BHP increase from a remap. Turbocharged yes but not NA cars, of any type. Just had a quick look 45 BHP increase, claimed and 74 NM increase, claimed for £349.

 

[Pond]

https://www.superchips.co.uk/ConfigOption/BMW/Z4/Petrol/sDrive18i-1997cc-156bhp/2013/vrm

It's got blower. As far as I can ascertain, the only difference with all those 2 litre engines is the map from the factory; ie 18 is 156hp, 20 is 185hp and 28 is 245hp. I may be wrong, maybe the 28 has a twinscroll turbo?

 

[Pond]

I will speak to them tomorrow if they're not 'working from home'.

I've used these people before and they are pretty good; not some bloke with a laptop who trades off the 'bay.

 

[andyglym]

https://www.superchips.co.uk/ConfigOption/BMW/Z4/Petrol/sDrive18i-1997cc-156bhp/2013/vrm

It's got blower. As far as I can ascertain, the only difference with all those 2 litre engines is the map from the factory; ie 18 is 156hp, 20 is 185hp and 28 is 245hp. I may be wrong, maybe the 28 has a twinscroll turbo?

I stand corrected

 

[Pond]

Look at this one for the other summer toy I'm planning. Look at the torque!

https://www.superchips.co.uk/ConfigOption/Mercedes-Benz/E-Class/Petrol/E500-Sport-4663cc-408bhp/2012/vrm

 

[andyglym]

Look at this one for the other summer toy I'm planning. Look at the torque!

https://www.superchips.co.uk/ConfigOption/Mercedes-Benz/E-Class/Petrol/E500-Sport-4663cc-408bhp/2012/vrm

Impressive

 

[Nodzed]

All the N20 IL4 2.0 ltr in the Z4s are the same, all twin scroll single turbos. The timing chain appears to be the number one fault on the N20, however, this issue is most common on engines produced prior to 2015. In January 2015, BMW redesigned the timing chain components, which seems to have significantly reduced the chance of failure. Be aware though the 28i has bigger brakes than the others, so if you go taking a 18i towards 28i 245 bhp performance the brakes may not be sufficient. Also you will have to tell your insurance company about the MAP.