Pharmacist

Wow. I came here after a very long time to see if there is any info on the next generation Z and lo and behold this thread is at the top of the page. Well let me give you my background.

In 2009 I bought a brand new Z with the sports package (back then the sports and nav packages were separate). I had an accident in 2011 which destroyed the car. So after getting the insurance money I bought a used 2008 E90 M3 sedan which I still drive. So I'm one of a very small group of people who owned and tracked both cars.

So let me give you my perspective as to how both cars compare. First of all let me state something which many people don't know of. The E90 M3 sedan is just as good and just as capable as the E92 coupe, the two cars are mechanically identical and have the exact same performance. The sedan in addition has more practicality, a slightly lower purchase price, and is a bit less common (they made 4 times as many coupes as sedans). The weight penalty for the rear doors is only 20 lb more thanthe coupe, which is negligible given how heavy the car is anyway. The coupe is not a bespoke coupe like the Z or vette or 911 is. The coupe is actually based on the sedan platform, with nothing more than minor modifications to the body panels and external skin of the car to make it 2 dr instead.

So let's compare the Z and the M. Let's start with the interor. The M definitely has the better interior than the Z. The materials are nicer, the interior more luxurious, more leather, better amenities, etc. The interior is also roomier and more practical, with more space for cargo and people. That being said, I think the M interior is actually somewhat subpar for its price tag. It's lifted straight from a regular 3 series without any real upgrades to it. I personally think BMW interiors are the worst among the German big 3, with Audi and Merc having much better interior. They also make a layout that is interesting, compared with the bland and boring BMW interiors. Speaking of layout, I found the Z had the better driver focused layout. I loved the large tachometer straight ahead. the M3 has a smaller tachometer offset to the far right of the dash, which makes it kinda useless on the track. The Z also had shift lights. BMW put shift lights on cars with the double clutch auto, but left that feature out on cars with the manual gearbox, for reasons no one seems to know. Go figure..

Exterior styling is subjective, but I loved the Z styling the best. I also like the bulldog look of the M3 sedan as well. Not really a fan of the M3 coupe styling. It's too bland and looks like any other 3 series coupe. And most of them have that ghastly and hideous carbon fibre roof as well.

In terms of practicality and utility the M3 is of course better than the z in this regard. It's a lot more comfortable whether on long trips or stuck in traffic, and there is much more room for cargo and people.

Now all of you are eager to know how they perform and drive. Since I drove both cars extensivley and tracked them several times, I'll say this. The M3 is faster. But not by much really. The M has the advantage in a straight line due to more power and better power to weight ratio. But the Z has better handling in the corners. If you upgrade the Z's crappy RE050 tires and on a track that doesn't favor hp and straight line speed as much, the Z will have no problem keeping up with the M. The V8 in the M is a lot more refined and smoother than the V6 in the Z. It revs up to 8400 rpm and sounds great while doing it. And at high rpm it makes pretty good power. However, low rpm torque is subpar, at 295 lbft which is marginally more than the V6 in the Z. So in day to day traffic the M3 can definitely feel sluggish and underwhelming. You have to downshift a lot and use the lower gears frequently to accelerate. Fuel economy is also abysmal. I average about 16l/100km. With the Z I think I used to get 14 or 14.5 l/100 km.

Now that the engine discussion is done, we've talked about the only thing in the M that is really special. The manual gearbox is pretty much the same as the Z, clunky and not very smooth, except the M shifter is even sloppier and more rubbery than the Z. The double clutch auto I've been told is fantastic, so it should be better than the torque converter-based auto in the Z, but I'm personally a manual guy so I couldn't care less about that. The steering is decent and communicative on the M, and I like the thick meaty steering wheel. But I feel there is a bit more power assist than I like, so I prefer the heavier and more direct steering feel that the Z had. Honestly among all the cars I drove the Z had the second best steering feel right after the Cayman.

The suspension on the M is a bit too soft and promotes understeer. The Z also had understeer and a soft suspension, but I feel this problem is worse in the M, probably due to the emphasis on more comfortable ride. Another issue is teh M's hefty weight. All modern Bimmers are bloated fat pigs, and the M3 is no exception. It weighs between 3600-3700 lb depending on options. So going from a Z to an M you definitely feel those exra 300-400lb of weight and the effect on the handling.

Last but not least, the brakes. I thought the Z sport brakes were reasonably good. With pads and fluid upgrade they held up decently on the track. The M's brakes on the other hand are a notorious weak point. BMW puts on those cheapo crappy single piston sliding calipers with tiny brake pads. A pad and fluid swap helps somewhat but given the weight of the car and the speeds it can reach, a BBK is a common upgrade among M3 track cars for better safety, heat resistance, and peace of mind.

The overall driving experience on the road is better in the M due to better comfort, ride compliance, and sound proofing. It's a more refined car. On the track, I found the Z be the better drive. Despite the coarse nature of the engine, the Z is lighter on its feet and turns in and changes direction better than the M. It brakes better. It steers better, with less understeer and better feel for what the chassis is doing. The shorter wheelbase and less weight make the car more dynamic and tossable. It's the more sporty of the two.

Maintenane wise, you'd be crazy to go to a BMW stealership. You will be ripped off big time. Knowing how to find good deals on parts and going to a good indy shop, or even better doing it DIY, will save you a lot of money. Doing it this way and doing the work myself, I find routine maintenance to cost about the same between teh M and the Z. Now if I was one of those who run to a stealership every time i need to put air into the tyres, I'll be singing a different tune! that brings me to another potential problem. 7 years after the E9x M3 platform was introduced, and in fact it is now discontinued, yet there is stil no factory service manual or any repair manual available anywhere for this car. The only service manual is on a website called TIS operated by BMW and requires an expensive subscription. There is a decent DIY section on the forums but it is by no means comprehensive. And sometimes finding something as simple as a torque spec on a bolt can be a real chore. And did I mention the engine has no dipstick? All you get is an electronic gauge that is not accurate, not precise, and not particularly fast to give a reading.

Reliability is actually not as bad as it seems with the M. It's not nearly as unreliable as other Bimmers or German cars in general are. There are a handful of known weak points and problematic areas. The idle air valve might fail on some cars. It's about $300. Each bank of 4 throttle bodies is operated by 1 actuator. Those actuators have a rather high rate of failure especially on higher mileage cars. Not difficult to replace. The problem is the part costs almost $1000 each, for whatever reason. Both of mine failed within a year of each other, costing me $2000 in parts. The bushings for the differential bolts are made from a soft material that might wear out on older cars, increasing the risk of bolts breaking. Aftermarket stiffer bushings are available for about $200 or so.

that brings us to the dark cloud hovering over the car, the piston connecting rod bearings! all of the recent NA engines by the M division had high bearing wear and the potential for engine failure. the S62, S54, S85 and S65 engines all have it. No one knows why that happens. But most people believe the cause is BMW using very small clearances between the bearings and the crank, coupled with an unusually thick 10w60 engine oil and very long oil change intervals. Some owners including myself have now switched to thinner oil and shorter oil change intervals. it is also possible that using crappy low octange gas causing detonation, or negligent owners pushing the car hard in the morning before warming up the oil first are exacerbating the issue. A very small but by no means negligible percentage of owners experienced destroyed engines due to rod bearing failure. It also turns out from searching the forums that no S65 engine or S85 engine (which is mechanically identical to the S65) that has been opened up so far did not show rod bearings with above average wear. Some people are now replacing rod bearings as a preventative measure. Some are monitoring it by using oil analysis to monitor any signs of bearing wear (in the form of elevated lead and copper levels on pre-2011 model year cars). The rod bearings issue is a very controversial and divisive issue among M owners. You can read about it on the forums if you want. Personally I bought my car with 70000 km on it and now I have it up to 139000 km. The engine is still running strong with no unusual sounds or any problems. Oil analysis shows very little lead and copper. I already switched to 0w40 oil in the summer and 0w30 in the winter. I might still replace the bearings, still weighing the issue. Not sure yet.

As for mods, you get pretty much the same with the Z as with the M, except M prices tend to be a bit higher. Superchargers for the M are available for between 550 all the way to 670 hp or so. Suspension and BBK kits can be picked up cheap second hand on the forums. Some people also do the subframe and differential bushings for better handling and reliability.

So there you go. My 2 cents on how the cars compare. The M is a pretty good car. But the Z is also an amazing car in its own right, and a heck of a car for the low price tag it has. the cars are different in character and purpose. The M is a grand tourer you can drive as a daily driver, go shopping in, and go for a spirited drive or a track day every once in a while. The Z is a sports car in the classical sense, all back to the basics mechanical equipment in a simple lightweight package. It's a blast to drive on the twisties, very fun on the track, and makes a great weekend toy, but not really meant to be an all around car or a good daily driver.
The M is softer, more comfortable, practical, refined, and luxurious. The Z is more loud, thrashy, masculine, agile, and dynamic. Take your pick based on what you prefer.

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2009 370z Sport Touring/Nismo shift Knob/Z1 motorsports 34 row oil cooler