New to tuning N54, looking for simple first steps - Cobb or Custom?

[gregrobin]

Hi forum, this is my first post. I recently purchased my 2nd BMW 335i. My first BMW was a 2001 330ci, my last one was a 2011 335i coupe with all of the packages, including M Sport. I loved the couple but I wanted a convertible. I now own a 2008 335i convertible automatic, one owner, excellent condition, 92k miles. This is a 2nd car, not my primary, driven on weekends for fun only. I am mechanical but these European engines are new to me. I grew up in the 70s and 80s working on small and big block chevy engines.

I want to add some HP and want smoother/quicker acceleration. I am not going to race the car. I just want to keep that big grin on my face every time I step on the gas pedal :-)

I've read a lot of forum posts on different ways to tune. From my readings I did some research on the Cobb Accessport. I contacted a local tuning shop to talk about this.

They recommended the following instead:

- Custom dyno tune calibration using MHD software - 93 octane
- cp-e cold-air intakes

They'd like to tune the engine to perform better on 93 octane fuel.

Their quote is $1029. The Cobb Accessport is $650 and looks straight forward to install.

Should I go custom, or go with Cobb?


Thanks,


Greg

[White94RX]

I would say it depends on your goals. If you just want a simple, off-the-shelf tune, and don't plan on continuing down the rabbit hole of vehicle modification, then go with the Cobb Accessport, or JB4 (I'm sure the two are similar). If you want to eventually add more and more performance parts, and will need to update the tune later on, then the custom tune route would be the way to go.

[pbonsalb]

I installed a JB4 on my 08 E61 535xi years ago. No other mods. I like it. Probably been on there 80k miles. No other mods since it is my wife’s car. Simple and effective. If you need to go further later, you can look into MHD and downpipes and intercooler and intake tubes and so forth. You can install one yourself if you are careful land patient. JB4 is not as easy as the Cobb but probably gets better reviews these days. Don’t be surprised if you need new ignition coils after raising the boost. The resulting cylinder pressure exposes the weakness of the original coils. S55 coils fit perfectly and are what I swapped in.