F32 435i Project Car

We continue looking into the future and what we might see on the grids in the coming years. We already took an in-depth look at what it took to build a competent and reliable N54 335i track car and now we're going even further by building an N55 435i track car. This is by no-means our first exposure with the N55 - BW owner James Clay has raced several M235i and M240i Racing models in the USA and in Germany, including earning the 2022 SRO TC Driver's Championship and 2022 BMW Sport Trophy.

The M235i Racing model is a special car and continues to be a fantastic club racing platform. That is a turn-key race car and we wanted to start fresh with a basic street car to see what it would take to build a proper N55 race car from scratch. We're going to do more than scratch the surface with bolt-on upgrades. With our history of racing factory cars like the M235i, M4 GT3 and M4 GT4 our standards are pretty high. How can we transfer that factory team car experience to everyone? We'll get into the usual power upgrades and brake and suspension improvements but we're also diving into the abyss of these late-generation F-series cars to understand the network of extensive electronics, vehicle coding, and other hurdles to building a safe, reliable, and fast N55 track car.

Video: Intro

We are diving straight into our newly acquired 2014 BMW F32 435i, equipped with a N55 and ZF8 automatic, and we are going to build a fun little racecar out of it.  Our approach will be build it as a very capable, quick, and more affordable version of a M235iRacing, or perhaps you could look at it as a GTMore without the M-car price tag.  Should prove to be a very fun and popular combination and we are about to show you the BimmerWorld way of how to build one.

Video: Post-Purchase Inspection and Disassembly Begins!

Follow along as Phil and the BimmerWorld team start dismantling the car to see how much weight it can shed and also document the process for future customers that will be going down the same path.  With these modern cars and so many modules and computers on board that are sensitive to change, we take a step by step approach to removing interior items and record how it changes the car - for better or for worse.

The 435i Post-Purchase Inspection

Before tearing into it we gave the car a quick go-over to look at common N55 problem areas: oil leaks around the oil filter housing, oil pan, and valve cover, coolant leaks from the various hoses and coolers, and a scan of all of the electronic modules. There's also several infamous and urgent items that need attention: the intake chargepipe and the coolant hose to the cylinder head (aka Mickey Mouse connector). We weren't overly concerned with brakes or suspension as all of that will be replaced as it progresses to a race car. Overall, our starter car is in very good condition with expected wear and tear and there's nothing any new owner wouldn't address anyway.

Video: BimmerWorld Unplugged

In the name of science, Phil and Dave did just that and in turn got the BimmerWorld F32 435i racecar build much closer to being ready to get on track.  Follow along while this modern BMW goes through a strict pre-cage diet plan while Phil makes sure he records the process to help other in the future do the exact same thing.

Simplify, then add lightness.

We've noticed two things at tracks and events around the country: no one wants to touch the electronics and “to go faster, just add power”. These are two misunderstandings that we want to correct as this project moves forward. We will attempt to remove the barriers that the modern electronics present to a clean and fully functional race car build. And as a bonus to the simplicity we will remove weight.

The power:weight conundrum is something that we often ponder. It's so easy to just add more fuel to the fire, crank up the boost, and make the car faster without taking any weight out. In fact, we add more weight with extra coolers, roll bars, etc. “Just crank up the boost!” is the common remedy for increased weight. But the already-hefty stock weight takes its toll on everything - tires, brakes, vehicle dynamics, and even engine and transmission wear. To make up for the hefty weight we're adding more stress to engine, transmission, cooling, and other systems. Not to mention spinning the turbo faster to a point where it becomes self-destructive. Add a bigger turbo? You'd better think twice because you're not addressing the elephant in the room.

This is why our F32 build series is starting with the un-sexy stripdown of the interior and electronics. Anyone can “go FBO” but that's not how it's done at our level. Imagine making the car faster and more reliable BEFORE touching the engine.

Video: F32 (and F82) Roll Cage Walk-Through

“The Devil is in the details” and in this video we go over some of the obstacles and solutions to installing a full roll cage in the F32/F82. Phil and James discuss the reasons behind a revised design, why it's not important to settle for “good enough”, and the fitment and installation of pre-built cage. Soon we will have this entire cage kit on this website, ready to ship to your door so you can create the exact same finished product and have a safe F32/F82 ready for the track.

When ‘Good Enough’ Needs To Go.

If you thought we were just going to add a rollbar and hit the track, you'd be wrong. If you thought we'd build a cage for style points, you'd also be wrong. We put a lot of thought and considerations into our cage designs [and time = money, btw] but the final result is something we'd bet our life on. Literally. This cage update video is a little overdue and that's because we threw out the first cage that was “good enough”. This second design checks all of our boxes while also over-coming some challenges in the F32 body.

Bonus Content: Grassroots Motorsports 435i Build

Coincidentally, our friends at Grassroots Motorsports have also embarked on a F3X N55 track car build. Their build is a true dual-purpose car, focusing on the N55's needs and upgrades to compete in SCCA Time Trials without stripping the car and affecting daily usability. Their build is already well along in 2024 so check out their growing library of F3X articles and videos -

grassrootsmotorsports.com/project-cars/2015-435i/