stolen this review from the Zpost member that has a high spec modded z4m and just purchased a GT4. Really enjoyed his review and honesty also. Very interesting. I need to get a drive in one of these things, peel back the drooling and really get into a proper review mindset to compare against my z4m.
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I didn’t mean to take anything away from the GT4, it’s amazing and I can’t stop driving it. It’s just that with all the media hype, raving automotive journalists, and marketing teams working hard to make every new car the most drool worthy ultimate driving machine that’s ever existed, I think it’s great to have some perspective and appreciate how lucky we are to drive the last naturally aspirated straight 6 ///M car. Particularly for this segment of enthusiasts that wants an old fashioned three pedal transmission attached to a gas guzzling high rpm naturally aspirated engine packed into a claustrophobic impractical sports car chassis, is “newer” better?
Full disclaimer, I’ve owned used BMWs all my life (E24 M6, E28 M5, E34 M5, E31 6-speed) so I’m definitely BMW biased and have a handful of auto-x and hpde days on my modified Z4M which isn’t stock so my perspective might be a little skewed. The GT4 is my first new car purchase, ever, and I only have about 2k street miles on it so far.
What I love about the new GT4:
I can’t believe this is an OEM suspension! The PASM adaptive dampers provide amazing control AND comfort even with the monster 20” wheels. At the same time, the stock set-up includes height adjustable coilovers and adjustable sway bars so other than a few shims and adjustable arms, the stock suspension is only a corner balance and aggressive alignment away from track ready. It’s all just a little soft and slow compared to the AST set-up on my Z4M which is really responsive and probably over-sprung at 550/650 but also so much more comfortable and streetable. I get the same occasional spring noises and clunks from the front springs moving around on both cars, cool. The stock Z4M suspension was crap.
Between the amazing suspension and mid-engine balance, the way the GT4 takes a corner is totally confidence inspiring. You sit right in the middle of the car, the front responds happily without a huge iron block sitting over the wheels on corner entry, and mid corner the car’s weight feels evenly distributed between the axles right along the outside line of the car. The Z4M on the other hand is more work to manage the distant feeling front end while sitting over the rear axle which, once you’ve managed the understeer up front, is now clawing every which way on the pavement for grip seemingly happier to swing sideways into oversteer than to actually push the car forward on corner exit. It’s super rewarding to get both ends to work together through the corner but I’m excited to get the mid-engine car on the track next year.
A side effect of the mid/rear engine layout and the transmission being directly connected to the engine is that the whole drivetrain feels more solid and responsive. I didn’t know what having a long driveshaft did to the feel of a car until it was gone but on rev matching, shifting, and on power application the connection between the engine and the rear wheels feels more immediate and direct. The engine also revs faster and more freely than the S54, it feels like the rotating assembly must weighs nothing in the flat 6. Above 4k rpm the engine really rips.
The steering, pedals, and shifter on the GT4 are heavier and more progressive than the Z4M. I hopped into the GT4 and drove away immediately feeling comfortable with the clutch and shifter and never giving them a second thought. It was like I had been driving the car forever. When I first drove the Z4M it made me feel like I didn’t know how to drive a manual with it’s combination of numb clutch and touchy gas pedal. It’s always bugged me that the brake and accelerator pedals felt relatively light and over boosted/sensitive especially compared to the clutch and steering on the Z4M.
Perhaps what makes the GT4 so appealing to me is that all the modifications I might make or already have made to the Z4M were either standard or options on the GT4. Oversized brakes with huge calipers and OEM brake ducts front and rear which I’ll never fade. Carbon fiber fixed back seats to support multi-point harnesses, built in airbags, and no stupid airbag light in the dash from installing aftermarket seats. Switchable exhaust to keep the neighbors happy and scream at the track. Awesome. I'm hoping to spend nothing on aftermarket parts for the car.... though I wouldn't mind some more power....
What I miss in the Z4M:
The steering! I always thought the steering in the Z4M was sorta numb but what makes it amazing is how fast and direct the rack is. There’s zero on play on center and it requires so little angle to get into a turn it’s like a video game. The GT4 might actually improve on the feedback side but it’s a slower ratio and there’s an artificial quality to it. It’s electric and a progressive rack with more boost at low speeds, less at high speeds, which actually gives it some good feel while on the move but it just doesn’t feel as consistent or authentic as the Z4M.
The gearing is stupid long on the GT4. Maybe this is a philosophical debate since the Z4M is geared similar to the E46 M3 and other ///M cars while the GT4 is geared similar to the 997 GT3 and other GT cars so I’m sure Porsche has their reasons but I miss the gearing in the Z4M. Gears 1-4 on the GT4 are way longer (2nd gear tops out at ~87mph!) and 6th is shorter so the low gears are slower and my cruising gear is higher. Go figure. I bet it’s faster on the Nurburging or somewhere else I’ll never drive. The shorter gearing and fatter torque curve on the low end actually makes the S54 feel equal if not more responsive around town under 4k rpm.
The layout and quality of the switchgear in the Z4M is way better. I’m sure I’ll get used to it but the GT4 layout is a crazy flight deck of buttons, most of which I almost never use but the commonly used buttons are the same size as the never used ones. The biggest surprise though is how clicky and cheap the buttons and turn signal stalk feel. In the Z4M all the buttons are soft touch with good travel, in the GT4 everything feels light, has little travel, and comes with a cheap feeling clickiness. This is all the more out of place given how lux the rest of the cabin is draped in alcantara, leather, and (fake) carbon fiber.
Sorry for the long post! Overall the GT4 is a great package and I'm super excited to get some track time with it in the spring. I'm sure it'll be faster on the track than the Z4M while also being the more comfortable road car but for just flat out enjoyment and driving fun, I think both the GT4 and a modded Z4M are up there.
For a fun afternoon drive in the mountains I would feel equally good grabbing the keys to either one.
Just when I thought I'd resigned it to nonsense, I walk past this
