BMW Z4 vs Mazda MX5 NC

[Cino]

I am looking for a convertible preferably with folding hard top and automatic. I would do a lot of commuting in traffic etc. as well as weekend drives so much prefer an auto for everyday. I have narrowed it down to MX5 NC or a BMW Z4, both from around 2010-2015. Anyone who has owned either or even driven both would be grateful for any insights. My concerns are:

Z4 - cost of servicing and parts, reliability

MX5 - I have heard they are prone to rust and I live near the sea, comfort on longer journeys, lack of acceleration (8.9 secs 0-60 from a 2L engine seems a bit underwhelming!)

I had an Audi TT roadster before and it had so many problems I had to sell it for virtually scrap value (07 reg) it was the least reliable car I ever had. I hope BMW aren't as bad!

Edited by Cino on Friday 31st May 20:38

Edited by Cino on Friday 31st May 20:38

[tr7v8]

I have an NC2 Mk 3.5 Its a Sport Tech so LSD, cruise & Bose. Its been reliable & is a nice place to be. Yes on the FB NC forum we have a few rusty ones but these are older ones (came out in 2005, so some are nearly 20 years old) A Bimmer of this age will be on a similar level of rust. Later NCs seem a bit better & plenty of people around will do a full protection job for £3-500.
Pre 2009 will be NC1 which is a weaker engine & they are all very sensitive to oil level. Low level & they'll kill the bottom end quickly. An engine swap is a far amount of work. The low oil is exacerbated by the fact that some use oil (mine doesn't) and people don't check the oil.

[Krikkit]

I'd have the Z4 3.0 N52 with the ZF6 gearbox over the Mazda - it's a lovely engine, the ZF6 is about as good as automatic gearboxes get with paddles etc for fun days, but proper slush for the commute. The second-gen Z4 doesn't suffer rust like the earlier cars either.

https://www.autotrader.co.uk/car-details/202405139...

tr7v8 said:

Pre 2009 will be NC1 which is a weaker engine & they are all very sensitive to oil level. Low level & they'll kill the bottom end quickly. An engine swap is a far amount of work. The low oil is exacerbated by the fact that some use oil (mine doesn't) and people don't check the oil.

Standard early Duratec problems, same thing plagues the Fords with that engine too. Shame as it's a good lump if looked after.

Edited by Krikkit on Friday 31st May 20:31

[TameRacingDriver]

Disagree on the auto with the Z4, I had one, ruined the car for me, and then failed expensively. Manual all the way.

Agree on the early NC oil burning. Mine did. And they rust, badly.

[Cino]

tr7v8 said:

I have an NC2 Mk 3.5 Its a Sport Tech so LSD, cruise & Bose. Its been reliable & is a nice place to be

What is the power / acceleration like? 8.9 secs 0-60 seems quite slow these days, my TT was 6.5 and didn't feel massively quick, so 2 and a half seconds slower than that sounds a bit sluggish?

[ambuletz]

Cino said:

tr7v8 said:

I have an NC2 Mk 3.5 Its a Sport Tech so LSD, cruise & Bose. Its been reliable & is a nice place to be

What is the power / acceleration like? 8.9 secs 0-60 seems quite slow these days, my TT was 6.5 and didn't feel massively quick, so 2 and a half seconds slower than that sounds a bit sluggish?

Missing the point of the MX-5 if you're looking at 0-60 times.

[TameRacingDriver]

Cino said:

What is the power / acceleration like? 8.9 secs 0-60 seems quite slow these days, my TT was 6.5 and didn't feel massively quick, so 2 and a half seconds slower than that sounds a bit sluggish?

8.9 seconds must be for the 1.8. The 2.0 NC is in the low 7s. It will also feel slower than a Turbo car like your TT due to having less low down torque (deployed at higher revs too).

[Cino]

ambuletz said:

Cino said:

tr7v8 said:

I have an NC2 Mk 3.5 Its a Sport Tech so LSD, cruise & Bose. Its been reliable & is a nice place to be

What is the power / acceleration like? 8.9 secs 0-60 seems quite slow these days, my TT was 6.5 and didn't feel massively quick, so 2 and a half seconds slower than that sounds a bit sluggish?

Missing the point of the MX-5 if you're looking at 0-60 times.

I had a Lotus Elise years ago so I know about the driving feel of a lightweight car etc. but that had strong acceleration as well. It's nice to feel that rush of straight line power as well as chucking it around twisty roads.

[Cino]

TameRacingDriver said:

Cino said:

What is the power / acceleration like? 8.9 secs 0-60 seems quite slow these days, my TT was 6.5 and didn't feel massively quick, so 2 and a half seconds slower than that sounds a bit sluggish?

8.9 seconds must be for the 1.8. The 2.0 NC is in the low 7s. It will also feel slower than a Turbo car like your TT due to having less low down torque (deployed at higher revs too).

The NC auto is 8.9, from the 2L engine. Not a dealbreaker, but nice to feel a bit of straight line shove.

[Cino]

[quote=Krikkit]I'd have the Z4 3.0 N52 with the ZF6 gearbox over the Mazda - it's a lovely engine, the ZF6 is about as good as automatic gearboxes get with paddles etc for fun days, but proper slush for the commute. The second-gen Z4 doesn't suffer rust like the earlier cars either.

https://www.autotrader.co.uk/car-details/202405139...

[quote]

What are the reliability and running costs like with the Z4? The 28i looks nice, 2L engine so more efficient but 245 bhp and 5.5 0-60, compared to 8.9 for the MX5

[Mr Tidy]

Contrary to what someone said earlier Z4s don't seem to suffer much from rust, and if they do it's only usually on the wings on the E85/86 models from 2003 to 2008. But seeing as all 4 wings are bolted on it isn't too hard to remedy.

The 28i you mention will be the later generation E89 model with the folding metal roof. That can have problems now they are getting older, often due to Salmon relay problems but they seem to be cheap and easy to replace. They can also suffer from splits in the wiring where the roof loom bends every time the roof is lowered or raised.

The 28i you mention has the N20 engine which is the same as fitted to the 18i and 20i that can both be easily mapped to 28i power. Some early ones have suffered from cam-chain issues. There were some revisions in 2015, mainly to the tensioner. I believe it can be replaced with the newer parts as a preventative measure for about £1K, but you might find one that has already had that done.

FWIW most serial Z4 owners agree the E85/86 are more Sports car than the E89 which is more Grand Tourer, but I've only had E86 Coupes so don't know myself. z4forum is well worth a visit for more detail.

Anyway good luck whatever you decide to get.

[Cino]

Mr Tidy said:

Contrary to what someone said earlier Z4s don't seem to suffer much from rust, and if they do it's only usually on the wings on the E85/86 models from 2003 to 2008. But seeing as all 4 wings are bolted on it isn't too hard to remedy.

The 28i you mention will be the later generation E89 model with the folding metal roof. That can have problems now they are getting older, often due to Salmon relay problems but they seem to be cheap and easy to replace. They can also suffer from splits in the wiring where the roof loom bends every time the roof is lowered or raised.

The 28i you mention has the N20 engine which is the same as fitted to the 18i and 20i that can both be easily mapped to 28i power. Some early ones have suffered from cam-chain issues. There were some revisions in 2015, mainly to the tensioner. I believe it can be replaced with the newer parts as a preventative measure for about £1K, but you might find one that has already had that done.

FWIW most serial Z4 owners agree the E85/86 are more Sports car than the E89 which is more Grand Tourer, but I've only had E86 Coupes so don't know myself. z4forum is well worth a visit for more detail.

Anyway good luck whatever you decide to get.

I belive that the 28i has a Turbo which the 20i and 18i don't have, which would explain the step up in performance. What are they like for reliability and servicing costs? The TT I had was terrible for constant problems, which put me off German cars a bit but I've never owned a BMW.

[aka_kerrly]

Cino said:

I belive that the 28i has a Turbo which the 20i and 18i don't have, which would explain the step up in performance. What are they like for reliability and servicing costs? The TT I had was terrible for constant problems, which put me off German cars a bit but I've never owned a BMW.

All of the Z4 models with 2.0L N20 engine have a turbo fitted with power ranging from 150-240hp, the 28I has tougher internals and as a result can be modified to produce more power safely compared with trying to achieve the same power from the lower range models.

The biggest issue with the engine was early production models having suspect cam chain tensioners, however, I'd argue that if this was only a problem on early model 2009-11ish that if the chain tensioners were going to fail "early" they'd have done so by now - this is very similar to the Nikasil fiasco BMW experienced, it was made out to be a inevitable yet many many of those engines are still running now.

If I were to go and buy a 2 seat cabriolet tomorrow for 5K and had to pick from your two choices id either go with a early E89 Z4 2.5SI or Z4 E85 3.0L ideally a later SI variant before considering a N20 powered car. As much as I want to like the MX5 NC and the folding hard top is a very good package ive convinced myself Id want much closer to or beyond 200hp to really want to keep it for more than just a summer.

Shame £5k doesn't get you a Honda S2000 these days unless you get quite lucky.

[CABC]

Z for the 6cyl engine. 5 for the chassis.
Getting a 5 to 200hp is 2k, best of both worlds.
Zs I’ve driven have been a handling disappointment.

[QuickQuack]

I got Little QQs have been lucky buggers, 1 had an NC1 hard top 2.0 sport and 2 who's a couple of years younger had NC2 hard top 2.0 sport tech as their 21st birthday presents.

I can confirm the oil issues with the early NCs, LQQ1 destroyed 2 engines through ignoring low oil level and then the noise the engine was making... And they both rust, not just NC1 but NC2 as well. I spent a fair amount getting the rust totally sorted on both.

I've no idea where the 0-60 figure of 8.9s comes from, especially for the 2.0L engine. Autocar managed it in 7.1s and the manufacturer official figure is lower, I think.

https://www.autocar.co.uk/car-review/mazda/mx-5-20...

While it doesn't pin you to back of the seat, the engine is an absolute peach and the car is a hoot to drive. LQQ1 eventually sold his but LQQ2 still has his. I love going for a spin when he's back home with it. I've driven a friend's Z4, and to be honest, I prefer the MX-5, but it's a very personal choice. The MX-5 felt more connected to the road and it's a proper manual with a very slick 6-speed gearbox instead of the paddles of the Z4. If you want to decide between the two, you must drive both, otherwise you'll always wonder what the other one drives like and whether you're missing out on a better drive.

[Cino]

QuickQuack said:

I got Little QQs have been lucky buggers, 1 had an NC1 hard top 2.0 sport and 2 who's a couple of years younger had NC2 hard top 2.0 sport tech as their 21st birthday presents.

I can confirm the oil issues with the early NCs, LQQ1 destroyed 2 engines through ignoring low oil level and then the noise the engine was making... And they both rust, not just NC1 but NC2 as well. I spent a fair amount getting the rust totally sorted on both.

I've no idea where the 0-60 figure of 8.9s comes from, especially for the 2.0L engine. Autocar managed it in 7.1s and the manufacturer official figure is lower, I think.

https://www.autocar.co.uk/car-review/mazda/mx-5-20...

While it doesn't pin you to back of the seat, the engine is an absolute peach and the car is a hoot to drive. LQQ1 eventually sold his but LQQ2 still has his. I love going for a spin when he's back home with it. I've driven a friend's Z4, and to be honest, I prefer the MX-5, but it's a very personal choice. The MX-5 felt more connected to the road and it's a proper manual with a very slick 6-speed gearbox instead of the paddles of the Z4. If you want to decide between the two, you must drive both, otherwise you'll always wonder what the other one drives like and whether you're missing out on a better drive.

8.9 is what I see listed most places as the 0-60 for the 2L automatic. I don't want a manual as it would be used for a lot of commuting in traffic as well. Was the rust obvious? I have read they can rust in places that can't easily be seen so you think it's clean but it's not. I live right by the sea which would make the rusting worse if they are prone to it, and would be looking at 9 - 14 years old for an NC.

[Cino]

aka_kerrly said:

Cino said:

I belive that the 28i has a Turbo which the 20i and 18i don't have, which would explain the step up in performance. What are they like for reliability and servicing costs? The TT I had was terrible for constant problems, which put me off German cars a bit but I've never owned a BMW.

All of the Z4 models with 2.0L N20 engine have a turbo fitted with power ranging from 150-240hp, the 28I has tougher internals and as a result can be modified to produce more power safely compared with trying to achieve the same power from the lower range models.

The biggest issue with the engine was early production models having suspect cam chain tensioners, however, I'd argue that if this was only a problem on early model 2009-11ish that if the chain tensioners were going to fail "early" they'd have done so by now - this is very similar to the Nikasil fiasco BMW experienced, it was made out to be a inevitable yet many many of those engines are still running now.

If I were to go and buy a 2 seat cabriolet tomorrow for 5K and had to pick from your two choices id either go with a early E89 Z4 2.5SI or Z4 E85 3.0L ideally a later SI variant before considering a N20 powered car. As much as I want to like the MX5 NC and the folding hard top is a very good package ive convinced myself Id want much closer to or beyond 200hp to really want to keep it for more than just a summer.

Shame £5k doesn't get you a Honda S2000 these days unless you get quite lucky.

You won't get a decent Z4 or MX5 for 5k these days, more like double that plus. Unless one with very high miles. I can go to about 13K max. Am I safe from the tensioner problem if the car is 2012 or younger? I read that there were quite a few issues with the cars from the early few years of that model which got sorted after about 2012.

[Tiglon]

Two completely different types of car, even though they're both 2 seat convertibles.

If you're going to spend most of the time stuck in traffic on the commute, then the Z4 is the better option. The cabin is a lovely place to be and, with the right tyres, wheel size and SE suspension it's a very comfortable ride.

The MX5 is all about the handling, not straight line grunt. Honestly, if you want a comfortable and powerful automatic, then I really don't understand why the MX-5 is on your shortlist.

The Z4 18i, 20i and 28i are indeed all exactly the same engine with a different map. You can get the 18i to 28i power levels very easily for a few hundred quid. I doubt you'll want one of the 6 pot engines if you're bothered about fuel economy.

[Cino]

Tiglon said:

Two completely different types of car, even though they're both 2 seat convertibles.

If you're going to spend most of the time stuck in traffic on the commute, then the Z4 is the better option. The cabin is a lovely place to be and, with the right tyres, wheel size and SE suspension it's a very comfortable ride.

The MX5 is all about the handling, not straight line grunt. Honestly, if you want a comfortable and powerful automatic, then I really don't understand why the MX-5 is on your shortlist.

The Z4 18i, 20i and 28i are indeed all exactly the same engine with a different map. You can get the 18i to 28i power levels very easily for a few hundred quid. I doubt you'll want one of the 6 pot engines if you're bothered about fuel economy.

The turbo is apparently different and bigger on the 28i. The power on the 2L MX5 is pretty much the same as the 18i but I imagine the feel of it is different.

[Tiglon]

Cino said:

Tiglon said:

Two completely different types of car, even though they're both 2 seat convertibles.

If you're going to spend most of the time stuck in traffic on the commute, then the Z4 is the better option. The cabin is a lovely place to be and, with the right tyres, wheel size and SE suspension it's a very comfortable ride.

The MX5 is all about the handling, not straight line grunt. Honestly, if you want a comfortable and powerful automatic, then I really don't understand why the MX-5 is on your shortlist.

The Z4 18i, 20i and 28i are indeed all exactly the same engine with a different map. You can get the 18i to 28i power levels very easily for a few hundred quid. I doubt you'll want one of the 6 pot engines if you're bothered about fuel economy.

The turbo is apparently different and bigger on the 28i. The power on the 2L MX5 is pretty much the same as the 18i but I imagine the feel of it is different.

Yeah, it isn't though.