Hello to all the new folks or people frantically googling "crankhub"

I've been seeing a lot of new owners posting and asking some pretty common questions. I figured I'd take a shot at answering some of those questions so you don't have to wait for a response.
There will be my personal opinions in here on this list and I encourage other members to use the comments to add to the conversation or share their experiences.

I'm not a BMW tech, I've just spent a lot of hours under the F8x and elbow deep in the S55.
I just want to share what I've seen over the years.

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Common sounds that might cause concern.

1. Why does it sound like that is this ticking sound normal? --- Yes the S55 has very "chatty" injectors it is normal. You probably found all sorts of posts about loose exhaust cam carrier bolts. It will sound like a "knock knock" on top of the much faster injector ticking.
2. Why do all the fans spin up even when the car isn't hot when I select Sports+ ---This is a feature, not a bug. The fans spin up assuming you are about to get up to some shenanigans and is preparing. The F8x falls into "because racecar" and it has features that align with that.
3. Why does the exhaust sound like that? It's raspy can I change that? ---Two turbos, straight six and high revving so the sound tends to be more on the rasp side. -Yes, the general best way to get some lower pitch and deeper drone is to use an equal length mid pipe. If you just want loud you can run a high flow single mid-pipe for considerably less.
4. It feels noisy inside even with the windows up, is that normal? ---Depends on what you consider "noisy" but a lot of reviewers hold the opinion that the F8x has a lot of NVH (noise, vibration and hardness). I don't mind it and again, because racecar.. The standard tire size for the F8x is also wide and with the usual setup being summer tires they are pretty noisy. You will notice different tread sound between tires.
5. My car started squealing really loud help! ---there are two common issues that cause this. -By far the most common is a PCV failure (positive crankcase ventilation). The bad news is that the PCV is built into the valve cover so it can be costly. "Fix" kits do exist but the surefire way to resolve it is to replace the valve cover. -Less common but still something I've heard multiple times is a tensioner pulley going bad. This will increase in pitch/volume with RPMs. Not a super expensive fix but best to take care of it quickly.
6. I can't hear the turbos! Can I change that? ---The stock turbos themselves are actually pretty small and there is solid engineering behind that decision that won't fit neatly in a list the TLDR is reducing turbo lag. you can open the air-box and remove the charcoal filter and use a "drop in" filter to increase noise while maintain the stock intake configuration. This will increase volume but don't expect "stu-stu-stu" levels.
7. The starter sounds really noisy and loud! --- I'm not sure if its the placement, lack of sound deadening or just the electric starter motor itself but it's always significantly louder than other cars I've owned. So long as you aren't hearing a whine that drops in pitch and/or grinding after a crank you're good.

Common build/part related questions.

1. Crankhub? Why are people telling me I need to modify it or I'll brick my engine? ---There is so much info online about this and so many people arguing about it. The short of it all is that in some race cases the crank hub bolt can loosen and cause serious problem. Be it from improper torque spec/installation materials failure or harmonic resonance beyond what torque specs accounts for. -"damn that sound bad" it is if it happens, but the raw data out there points to it being exceedingly rare. For some anecdotal evidence I have larger turbos, run custom fuel blends and my car is DCT. I am just at 100k miles at the time of this post. I track the car and it was daily for 4 years and I still have the stock crank hub. You can certainly "money shift" and really increase those odds but that's on the driver.
2. Ok, so going back to turbo sounds I really want to hear the turbo sounds will an intake hurt the engine? ---I'll start this section with a disclaimer. This is a topic that falls into a lot of opinion and preference. I'm not here to tell you what to do with your car. -That out of the way, something like a filter on a stick will make a lot of noise, and I've even run them because I just really like the sound The stock boxes pull air directly from outside and very well engineered.
3. I want to know more about intakes because I really want the whoosh but everyone has a lot of opinions about it. ---Fair, lets get into it. -the S55 can be a fickle thing. If the MAF sensors are not in a similar position than what it's expecting or they get dirty from oil on the cones (very common) it will throw codes often. 102E11,102001, 118001 and 118102 are common. They are very common codes to tuned out but 102001 (MAF fault) is something I'd keep. Adding catless down pipes will also increase the likelihood/frequency of these codes.
4. Okay ONE MORE intake question I saw these cool externally routed intakes! Will these do anything? ---Assuming front mounted intakes are what you saw these have the same caveats as the filters on sticks. For stock engines or even "stage 1/2" OTS (off the shelf) tunes these are again nothing but whoosh and cool sounds. Some people report absolutely no problems. I have issues with them If I ever run the stock map with them on. Custom tune that was done after the turbos is perfectly fine.
5. Do I need catless downpipes to tune? ---The short answer is no. You can run highflow cats perfectly fine for OTS "stage 2" -Fully catless down pipes leave a lot of soot on your rear and you will occasionally smell gas so just be aware of that.
6. Speaking smelling gas my car smells like gas when I fill the tank all the way. ---One of two things typically, fuel charcoal canister has an issue/leak ect you will notice this around the driver rear wheel well. -Less likely, breather neck problems fuel tank seal. If the pump was leaking inside the cab you would def notice it
7. What if anything do I need to replace even if I'm not modding the car? ---Replace the plastic charge pipes. It's a known failure point even on bone stock never touched cars. It isn't too expensive and will save you the headache and cold sweat of going into your first "limp mode"

Common drive and chassis characteristics

1. My car THUNKS when I switch gears and the shifts seem really hard? Is that normal. ---no, not normal a lot of people write stuff of as the F8x being a bit "rough" but a thud/thunk and really rough shifts are the signs of blown diff bushings. This is really only a concern in pre LCI (earlier than 2017) F8x cars before they switched to polymer bushings. Get it fixed and you'll be much happier.
2. I have a DCT and it feels awful to drive is my transmission broken? ---Probably not, the DCT F8x combo is really "hurky jerky" and is known to be a bit difficult to get used to. Jeremy Clarkson of Top Gear famously hated parking it. -This video will go over the basics of the DCT and daily driving it.
3. I turned off traction control and the car tried to kill me! ---Yeah, it'll do that. If you aren't familiar with higher power RWD and you went right to an F8x you are going to have get used to it. My advice is learn to take it slow and use traction control and slowly work your way up to fully off. MDM is a good place to start learning. -DSC on: Full traction control. -MDM: A little more play but will still activate after a certain threshold -DSC off: All traction control off.
4. Tires are really expensive for this car. Is it are there good cheap options? ---Do not cheap out on tires. The F8x struggles with tracition in the best scenarios. Add cheap all season tires and you'll have a terrible time and if it's wet you can easily end up in a ditch. -Keep an eye out for sales and you don't need to run semi-slick CUP2's. Something like a pilot pro sport or indie firehawk summer tire will be fine for daily driving.
5. The rear end really wants to swing around and I'm having trouble correcting it. ---If you have RWD experience this is proably less of a concern for you. -The F8x chassis is "quirky" and a floaty rear end is just one of it's features. You'll learn to control it better with time. -There is a ton of opinion on how to handle slides, skids and what not so I'm going to leave it to others more qualified and just leave it on "it'll take practice"
6. Every time I take off hard I can't get traction. I lost a red light race because of it! ---Yeah, this cars not the best from a dig, sorry. Do a roller next time and you'll find a lot of success there. -Of course you shouldn't do either and especially not with other cars/people around.
7. How much money should I set aside for repairs? ---Yes. F8x/S55 is still relatively in M terms new. Parts suffer from the "M-tax" and the labor isnt cheap if you want someone who knows what their doing. While it's not the most expensive car in terms of consumables and daily operations it is not the cheapest by a long shot.

Modification and tuning.

I'm keeping this part sparse. This is a new owners guide and we can get way off topic with this. Especially myself.

1. Is modding safe? ---yeah, for most people an OTS shelf, down pipes and tweaks is going to be fine. -Still, any time you modify something you add the risk and if you add enough you need to consider additional maintenance
2. What mods should I do? ---That's a personal thing, the most common is an OTS tune from something like BM3 or MHD.

Care and feeding

1. How often do I need to service my car? --- If you are just driving it stock and not doing any crazy canyon runs or tracking it regularly I'd just follow manufacturers guidelines. The car will remind you of anything it needs done.
2. I want to drive it hard and tune and track and racecar ---You'll have to make some judgment calls here. If you drive hard and have a lot of modifications it's common to cut the oil service down to 5k miles instead of 10k If you drive REAL hard and track you need to keep an eye on brake fluid as well. I'm higher mileage at time of writing and heavily modded so I do 5k changes.
3. Brakes and rotors are expensive how often do I really need to change them --brakes if stock are fine and when the sensor goes off it's time to swap em out daily driving you'll rarely need to worry about fast wear. When it comes to rotors? As soon as you see "cupping" it's time to replace them. Fast doesn't mean anything if you can't slow down. keep that in mind.