4 cylinder turbo 2.0l vs 6 cylinder 2.5l - Should I buy a Z4 E89 28i or 23i ?

[Lazam1985]

So I love the fact you get the straight 6 with the 23i

But the 28i with is newer year and newest engine although is a 4 banger still produces great results hp higher torque


So what you guys think get the 6cylinder or the uprated 4 cylinder turbo


I guess other things to consider I would want to get M sport option .
is there any difference with M sport upgraded parts between the two models ? are the m sport components the same in the m sport 23i and the m sport 28i?

Also I will get an automatic version. is the later model 28i automatic a much better transmission than the 23i. Or is it pretty similar to the 23i?



Any advice you guys have, let me know thanks


Also any models years to avoid etc


Thanks Loz

 

[Ole gits rule]

A lot of people will say the 6 cyl is a fantastic engine which very rarely causes any issues, is good on fuel and sounds pretty good even in the 23i, some will say its underpowered but mine has been fine for my needs.

Why a 28i, this limits your choice get a 20i and a remap unto 28i performance or more if wanted, this will widen your choice and save you a fortune when buying as the 28i carries a premium.

I don't think there is any difference in the trim, in fact not much changed on the LCI version of the 4 pot, no idea on the auto box.

My advice, drive both and buy what you prefer, every one has their own opinion and will all be different to yours.

 

[B21]

The MSport package largely carries over from the earlier 6 pot to the later 4 pot versions.

The 4 pot auto box ZF8HP45 with the N20 is a second generation improved version of the ZF6HP26 fitted to the N52.

The N20 and ZF8HP is a great marriage.

As discussed remapping a 18i or 20i is easy and usually exceeds by 25-35 BHP the power of the 28i..torque often goes close to 450nm.

On the N52 there were no particular production run issues.

On the N20 pre April 2015 versions have a weaker camchain sub system that in some cars does fail..a whining sound is the obvious indicator ..you can get an uprated cam chain kit fitted for around £1k.

N20 cars tend to be better spec’d and dynamically are better than the N52s if that matters.

The N52 protagonists argue large engine in the engine bay, six pot exhaust sound and a well proven engine.

 

[Silverstar]

If you are considering the 28i why compare it to the 23i, a more suitable comparison would be a 30i. Personally I would always choose a 6 cylinder or more over a 4 pot in a BMW so I am a bit biased as for me it would be a 30i or 35i/s but if you are looking at a 28i then as others have said cheaper to look for a 20i and have it mapped.

As for the gearbox I had the ZF 8 speed in my previous 2016 F20 and currently have the ZF 6 Speed in my E89. Now in terms of gearboxes I have a taken a step back, yes the ZF8 speed is a better box but I didn't feel I was missing that much downgrading to the ZF 6 speed. I have flashed my ZF6 with XHP Flash and it has made the box that much quicker it's a vast improvement.

Finally getting back to the 30i it has more power more torque same fuel economy / running costs as the 23i but with probably better resale value due to it's comparative rarity.

 

[Pondy]

Well I have a lowly 18i (exactly the same N20 engine as the 20i and 28i), which has had a £279 remap. I can honestly say that apart from a 3 litre turbo 6 banger BMW engine, I wouldn't need anything else. The torque and 'grunt' is now quite remarkable and it is a very fun place to be!

 

[Lazam1985]

Hey guys thanks for all your info and suggestions


Looks like best if getting n20 to just remap like you say sounds relatively cheap way to add more power


As for the 6cylinder I have found a n54
3.0 Z4 SDRIVE35IS

Going for sale with 55k mileage



How is that engine? I keep finding mixed reviews saying is super easy tune, but others saying so many issues ?

Any thoughts on the n54?

 

[B21]

N54 has many big time problems that will happen to the previous, current and future owners..

Many make the cam chain issue on the N20 look small beer.

It is very easy to tune…the easiest of all E89s.

If you can afford to take potentially multiple £2k hits and feel the need for Saturn V acceleration with the worst handlimg of any E89 then step up

 

[Chippie]

The N54 is a great engine, easily tuned and very reliable, the problem with the internet and forums is that you always get people saying what problems they have and generally how great and reliable it is, although there are several issues to be aware of.

With it being direct fuel injection the inlet valves coke up and need cleaning at around 70k miles (walnut blasting).

Failing fuel injectors can be a problem, currently on revision 12 which seem reliable.

Electric water pumps tend to fail between 60k and 80k miles.

High and low pressure fuel pumps can also fail anywhere from 30k miles.

The turbos can develop a waste gate rattle, it can be heard when lifting off the throttle and the engine dumps the boost.

Oil leak are common, oil housing/cooler, engine sump and the DCT gearbox seals.

I’m very happy with mine, just be prepared for some expensive repairs, although you may be lucky and not have to spend much.
You really need to test drive a few different models to get an idea of what you’d like, although I jumped straight in with a 35is and have no regrets.

 

[Marcoose]

IRT 35is handling. Yes, stock is a total pig. Massive understeer. If you want confident handling for spirited drives, you’ll be looking at US$5,000 of upgrades.

 

[matsmith749]

Handling issues are over rated IMHO.

If you want the sharpest scalpel in the box, are considering track days, or like to blast >80 down back roads - the e89 is not a great choice full stop. No matter what you do to modofy the handling, it will remain overweight. Get something more suited IMHO.

Throwing race car money at an e89 will not ever make it a race car - you are asking for big bills & ultimate dissapointment when you finally have a go in something that is built to be sharp. (any boxter, 911, 968, justabout any other porsche, alpine A110, anything 2 seater <1200kg). Even an e85 z4 3.0si sport.

For normal driving within the speed limit & the occasional hoon, it's just fine as it is (change the tyres to something UUHP non-runflat excepted).

 

[warmasice]

4 pot turbo here remapped. Will easily outperform a 23i. Granted the straight 6 sounds good but let down by its asthmatic performance and a little lardy with that bulky engine.

 

[Silverstar]

4 pot turbo here remapped. Will easily outperform a 23i. Granted the straight 6 sounds good but let down by its asthmatic performance and a little lardy with that bulky engine.

Or just go with the 30i on par performance to a tuned 20i and you get that lovely soundtrack as for handling well as matsmith749 above put it, the E89 isn't a track car, just accept it for what it is.

 

[warmasice]

4 pot turbo here remapped. Will easily outperform a 23i. Granted the straight 6 sounds good but let down by its asthmatic performance and a little lardy with that bulky engine.

Or just go with the 30i on par performance to a tuned 20i and you get that lovely soundtrack as for handling well as matsmith749 above put it, the E89 isn't a track car, just accept it for what it is.

You're getting upto an extra 100ft lbs of torque with a remapped 20i over a 30i which isn't insignificant coupled with a lighter engine it's definitely has it's advantages. Granted, the straight 6 does sound good.

 

[True-Blue]

4 pot turbo here remapped. Will easily outperform a 23i. Granted the straight 6 sounds good but let down by its asthmatic performance and a little lardy with that bulky engine.

Or just go with the 30i on par performance to a tuned 20i and you get that lovely soundtrack as for handling well as matsmith749 above put it, the E89 isn't a track car, just accept it for what it is.

You're getting upto an extra 100ft lbs of torque with a remapped 20i over a 30i which isn't insignificant coupled with a lighter engine it's definitely has it's advantages. Granted, the straight 6 does sound good.

I agree that a mapped 2.0 is a touch faster than a 3.0 N52, but there’s always ‘something faster’

The 2.0 turbo has fake engine noises piped into the cabin, so to make it sound interesting when pressing on. Sadly, it doesn’t have noise cancelling when moving at slow speeds to counteract the diesel like soundtrack of the high pressure injectors

OP if you go with a remapped turbo car I’m sure you’ll love it, it’ll be fun. If you can find a 3.0 N52, it’s the last of a dying breed and it’s a glorious experience even if fractionally slower than a remapped 2.0. At least you won’t have to stress about the engine eating itself

 

[Silverstar]

Or just go with the 30i on par performance to a tuned 20i and you get that lovely soundtrack as for handling well as matsmith749 above put it, the E89 isn't a track car, just accept it for what it is.

You're getting upto an extra 100ft lbs of torque with a remapped 20i over a 30i which isn't insignificant coupled with a lighter engine it's definitely has it's advantages. Granted, the straight 6 does sound good.

I agree that a mapped 2.0 is a touch faster than a 3.0 N52, but there’s always ‘something faster’

The 2.0 turbo has fake engine noises piped into the cabin, so to make it sound interesting when pressing on. Sadly, it doesn’t have noise cancelling when moving at slow speeds to counteract the diesel like soundtrack of the high pressure injectors

OP if you go with a remapped turbo car I’m sure you’ll love it, it’ll be fun. If you can find a 3.0 N52, it’s the last of a dying breed and it’s a glorious experience even if fractionally slower than a remapped 2.0. At least you won’t have to stress about the engine eating itself

It would be interesting to put the two cars to a drag race and see exactly what the difference is between a 30i and a chipped 20i. 20i might be a tad quicker but shouldn't think by much, trade off is the fantastic soundtrack and silky smoothness. As the bloke says in the Highpeak video 6 cylinders just feels more special and substantial.

 

[B21]

In a drag race the re-mapped N20 would beat the 30i to 60mph by 0.5 to 0.7 of a sec…the dash to 1km would be about a second faster…

Not really the point..on the twisties with the same competent driver the re-mapped N20 would just scoot off into the distance…substantially broader, fatter torque, more power over a broader range, lighter weight, better handling..

But yet again it’s more in the driver than in the car..

The engine just sounds different…a bit of turbo whistle and a different octave..

Folks droning on about the noise and smoothness of the old 6 are just in denial that the N20 whooped the N52…albeit with a blot on the camchain landscape..

Bit like folks bemoaning the demise of side valves…

Every dog has its day and the N52 had a long and noble life..just the N20 delivered a successor ..and it’s successor the B48 was even better..

Sure if you want silly BHP / torque then a N54 or B58 is your friend …

If I was re-living my E89 journey I’d have started and stopped with my N20 ZF8HP Quaife LSD Big `turbo uprated camchain baby..but hindsight is a wonderful thing..

But each to their own and I just don’t think we should disenfranchise folks on some religious dogma..

 

[B21]

Or just go with the 30i on par performance to a tuned 20i and you get that lovely soundtrack as for handling well as matsmith749 above put it, the E89 isn't a track car, just accept it for what it is.

You're getting upto an extra 100ft lbs of torque with a remapped 20i over a 30i which isn't insignificant coupled with a lighter engine it's definitely has it's advantages. Granted, the straight 6 does sound good.

I agree that a mapped 2.0 is a touch faster than a 3.0 N52, but there’s always ‘something faster’

The 2.0 turbo has fake engine noises piped into the cabin, so to make it sound interesting when pressing on. Sadly, it doesn’t have noise cancelling when moving at slow speeds to counteract the diesel like soundtrack of the high pressure injectors

OP if you go with a remapped turbo car I’m sure you’ll love it, it’ll be fun. If you can find a 3.0 N52, it’s the last of a dying breed and it’s a glorious experience even if fractionally slower than a remapped 2.0. At least you won’t have to stress about the engine eating itself

You’re incorrect..the ‘diesel’ clatter comes from the cam shaft driven vacuum pump..with DI engines there’s no inherent engine vacuum so it’s had to be augmented by an engine driven pump..

 

[True-Blue]

In a drag race the re-mapped N20 would beat the 30i to 60mph by 0.5 to 0.7 of a sec…the dash to 1km would be about a second faster…

Not really the point..on the twisties with the same competent driver the re-mapped N20 would just scoot off into the distance…substantially broader, fatter torque, more power over a broader range, lighter weight, better handling..

But yet again it’s more in the driver than in the car..

The engine just sounds different…a bit of turbo whistle and a different octave..

Folks droning on about the noise and smoothness of the old 6 are just in denial that the N20 whooped the N52…albeit with a blot on the camchain landscape..

Bit like folks bemoaning the demise of side valves…

Every dog has its day and the N52 had a long and noble life..just the N20 delivered a successor ..and it’s successor the B48 was even better..

Sure if you want silly BHP / torque then a N54 or B58 is your friend …

If I was re-living my E89 journey I’d have started and stopped with my N20 ZF8HP Quaife LSD Big `turbo uprated camchain baby..but hindsight is a wonderful thing..

But each to their own and I just don’t think we should disenfranchise folks on some religious dogma..

Who’s disenfranchising anyone?

Not everyone wants to be the fastest kid on the block in the brightest coloured car do they?

Anyway, having owned an N20, and despite agreeing it was a bit faster than the N52, I know which lump I prefer

 

[Silverstar]

Folks droning on about the noise and smoothness of the old 6 are just in denial that the N20 whooped the N52…albeit with a blot on the camchain landscape..

This is totally incorrect. I have driven the 18i 20i 23i and 30i and made my choice to get the 30i. The 18i and 20i were standard and not chipped so less performance than the 30i but that isn't the reason I chose the 30i. I chose it because the 30i sounds great and make the car feel more special not necessarily the fastest around corners. If I wanted a car that did that then I would have just gone for the Boxster / Cayman which would probably out do any E89 around the twisties. The N20 in its most common variant most certainly did not whop the N52.

 

[True-Blue]

Folks droning on about the noise and smoothness of the old 6 are just in denial that the N20 whooped the N52…albeit with a blot on the camchain landscape..

This is totally incorrect. I have driven the 18i 20i 23i and 30i and made my choice to get the 30i. The 18i and 20i were standard and not chipped so less performance than the 30i but that isn't the reason I chose the 30i. I chose it because the 30i sounds great and make the car feel more special not necessarily the fastest around corners. If I wanted a car that did that then I would have just gone for the Boxster / Cayman which would probably out do any E89 around the twisties. The N20 in its most common variant most certainly did not whop the N52.

To quote Shaggy… it wasn’t me… that said that