[DM6]

Originally Posted by PinkNinja400Guy

I test drove both of these cars recently, and the results were surprising. Here are my thoughts (warning, long post).

The Miata has a number of downsides - power, storage space, and comfort. My initial pre-drive expectation was that the Miata would be much more fun to drive (stick shift, and 2300 lbs vs ~3500 lbs).

My plan for the test drives was to evaluate if any of the disadvantages of the Miata were severe enough to be dealbreakers. If not, then buy the more fun Miata, otherwise settle for the Z4.

The Miata had just enough storage space to fit all the stuff I need to fit into it, and noise at speed was not intolerable. It was comfortable during the 30 minute test drive. So, the decision would be to buy the Miata, right? Not quite...

The Z4's handling was shockingly good. I'll add a disclaimer that I tested the Miata in the Denver suburbs, and the Z4 in downtown Denver in traffic, so I had limited ability to evaluate the Z4, but I did get a few chances to throw it around corners. And overall I've only spent a small bit of time with each of these vehicles.

The Z4 almost feels like it's lower than the Miata. The Z4 seat adjusts very far down (though you can mod the Miata to lower its seat as well). The Z4 is also 5" wider and has a wider track.

Whereas the Miata is "tall" and has body roll through corners, the Z4 sticks to the ground like glue. It stays very flat and just grips through turns. Though the Z4 is more than 1000 lbs (50%) heavier, you don't really feel the extra weight. Maybe on a mountain road at higher speeds and/or going downhill you'd be able to feel a bigger difference, but I was really impressed by the handling of the Z4 in Denver. The raw 50% weight difference stat is very misleading. I don't know if the Z4 has a lower center of gravity than the Miata, but it felt like that. It does a great job of hiding its weight.

When I drove the Miata, it felt less stable when turning... as stlcdr pointed out in his post, the Miata felt "jittery" through turns. I suspect this is because of a few things: The body roll intentionally designed into its suspension; its lower weight; and its lower chassis rigidity. Chassis rigidity isn't really something you actively notice when you drive a normal car, but the Z4 felt a lot more solid and stable through corners, and in hindsight I suspect its high rigidity is the main reason for that.

I didn't mind the automatic transmission in the Z4. The stick shift in the Miata was nice but I didn't really miss it much when I drove the Z4 (after the Miata). That's not what I was expecting.

The engine in the Miata also felt boring and lifeless, which is also not what I was expecting given that it's naturally aspirated. The sound was mediocre, and it's not quick by any means (which is part of the car's philosophy, but still). The Z4 M40 is really fast - too fast to enjoy on the street, in my opinion - and the B58 sounds nice. There wasn't a 30i available for me to test drive, the 30i would give you a more reasonable (yet still large) amount of power but you lose out on the B58 soundtrack.

The Z4 interior has a lot of space. The seat can move quite a bit up/down, and also forward/back (I'm 5'11" and I can barely reach the pedals with the seat back). There's a ton of width around the seat so large people can easily fit in the Z4. On the other hand, if you're not too tall or wide, the Miata interior fits tighter around your body which feels good in its own way. And though the Z4 does a great job of hiding its weight, the Miata definitely feels like a smaller car - it's 16" shorter and 5" less wide, and you can tell.

The Z4 has a "wall" behind the seats which is pretty tall, when you look back you see that wall and the speakers inside it. The rear end of the Miata isn't as tall which gives it a more open feel. Seat height adjustment could be a factor in this, I didn't spend much time dialing in the Z4 seats, and the previous test driver had left them pretty low.

Obviously the interior of the Z4 is much, much nicer, and it also looks better than the plain all-black Miata interior. The Z4 has more storage space on the interior, and a much bigger trunk. It also has better features - iDrive 7, parking sensors, auto hold, radar cruise control, adaptive suspension.

The Z4 would also be better for cold weather driving. It doesn't have a neck warmer like the higher end convertibles, but it has a heated steering wheel which the Miata doesn't. The Z4 soft top is rated for operation down to 14 degrees F which is much better than the Miata's 45 degree rating.

BMW traction control & stability control is superior to the Mazda system, which is great to have regardless of the weather.

So overall, I'm not sure which one to go for. You can certainly mod the Miata to remove the body roll, stiffen the chassis, lower the seat, and maybe lower the entire car. Adding a turbo onto the engine is also fairly easy. That'd get you a good handling and very compact/lightweight car. The Z4 is "pre-upgraded" from the factory, so you don't need to spend time tinkering around with it, but you pay a huge premium for that - $35k for Miata GT soft top vs $65/75k for a fully optioned 4/6 cylinder Z4 (identical apart from the engine). Add on sales tax, ad valorem, and ongoing insurance/fuel/maintenance, and there's a huge cost difference.

You literally made no case for purchasing a Miata, whatsoever. Read your post again, I think you know which one to go for.

[Tuxedo]

I've sold both, driven both very little compared to any owners. MT Miata at 5-6k revs is a blast, lite and toss able I would def want one to track but it's not user friendly as a daily driver imo. Z4 is well planted, the tire contact, the heavy feel, daily ready with a lot more driver seat recline and trunk size. Compare the 2 by price alone 4cyl Z4 the Miata is a no brain'r for me, when the MT Z4 M40 I'm in. If you're tall in the torso Miata is no go, over all height doesn't always matter for the Z4.

I could go to Costco buy $300 household supplies in the trunk of a Z4 but not a Miata for example.

[danbart]

I had a pretty modded NC that was a ton of fun. Supercharger, Suspension, Chassis bracing, bigger tires, wheels and brakes.

Loved the car. It was a hoot to drive. Was perfect for improving your driving skills since the road feedback was so good. You could tell exactly when the suspension was loaded up in a corner entry and when the wheels were about to break loose. Car and body were connected almost telepathically, plus you had a blast at near legal speeds.

The down side was that it was a bit cramped and uncomfortable, and in the end lacked the TQ and HP that make a car more fun. I always dreamed of a LS swapped Miata. I can only imagine how fun a V-8 NC would be.

[danbart]

I just added the https://www.aleksracing.com/ultrarac...bmw-z4-g29-ur/ full chassis bracing package and it really improved the feel and handling of the car. Really tightened everything up at a very reasonable price.