The "Lil 1" 135i Build — From Weekend Toy, to 1M Widebody Time Attack Car

[thisisluka]

Hey y'all — Been a bit of a long time coming making a build thread of this thing, but figured with work being slow, and there being 6" of snow on the ground here in Chicago, that it'd be a good opportunity to take a stab at my first real forum build post on here. So here goes nothing.

How we started vs where we're at now:




(2/28/23 → 9/14/24)


As you can probably gather, I've gotten pretty far in the process for where I'd like to take it. Far from done - in my opinion I still have plenty to do & improve, but figured better late than never to start this thread, and try to keep it regularly updated from here on out.

A bit of backstory: (skip ahead if you wanna get straight into the meat of the build)
Had an E90 335i for roughly 7 years & 160k mi as my first car back in college at UIC. It kinda set the foundation for everything I'd come to learn about the almighty N54 platform, alongside, in my opinion, one of the best chassis BMW would ever develop in the e9x/e8x. Was my daily, but the goal was to get it dual duty ready, & hit the track after a handful of auto-crosses over the years.





All good things come to an end, and after its last year of daily duty hanging around 550whp, got unlucky over some black ice the first real cold night of fall a few years back, and put the thing into a Chicago light pole at 40mph. Not my proudest moment, but we live & we learn.





At least having the front subframe torn in half made it easy to get the Pure S2's I put in it easy to get out & sell lol.

Picked up an N55 powered F25 Msport X3 in hopes to try and limit myself, (I know I'd get the bug to go all out again if I picked up another car) and fell in love with the thing. Was the perfect balance of sporty-ness, & creature comforts, both before and after some light mods. Simple stuff for a street build really — wheels/tires, KW coilovers, FBO suite from VRSF, MHD 2+ OTS's, XHP S3, and a more modern CarPlay unit, and was a perfect tasteful all around-er for the money. Had space for everything, and even being lowered, didn't have to worry about getting over those atrocious Chicago alley speed bumps, or feeling my soul leave my body going over lakeshore drive's endless imperfections before it got repaved. Iykyk.



As fun as the thing is, I missed being able to go on some more spirited cruises with my friends in something smaller & more nimble. Missed that connection from the hydraulic rack in the e9x chassis, that the F25 left me feeling numb with, despite being an incredible daily.

Fast forward a year later, after pondering an e36 m3 clubsport build I even started to collect parts for, a friend & fellow Facebook marketplace jockey sent me a golden listing that I just couldn't refuse.

So a few quick messages back and forth with the seller to gauge if this thing was legit, we packed into the X3 and drove over 3 hours out to middle of nowhere Princeville Illinois to strike a deal.

Behold, what my close friends would coin as the "Lil 1" in all her god awful offset, shitty generic tire rack winter wheel'd setup glory. Alongside my shit eating grin of excitement. It's not every day you buy your first manual car.



2/26/23


Now contrary to the vast majority of N54 powered cars being long molested by countless careless owners by now, we found a bit of a diamond in the rough.

Two owner car - first owner took it to the dealer and spared no expense maintaining it, as what seemed to be a primarily highway mile'd daily.

Second owner? The BMW Master tech that did all the maintenance. Score.

Despite a blown rear shock and some typical wear to the interior & paint work, the thing was in fantastic shape, and was incredibly well kept, despite having racked up 189k mi on the clock.

Yep, you read that right. Still somehow on factory turbos too, confirmed from the master tech as never being replaced. No smoke, still made boost (and despite being pretty tired & lazy, somehow still do even to this day, after two seasons of track days and time attack events lol) but later on definitely had a bit of waste gate rattle, but that was easy to adjust out.





Msport, black sapphire metallic over coral red interior, with 3 pedals, sport heated but manual seats, and no nav. An ideal stripper spec minus the black headliner imo. Fixed that pretty early on though, grey headliner sucks.





Stock, never tuned, or modified outside of an aluminum charge pipe & genuine Tial BOV given the frail plastic stock piece, and then he ordered directly from BMW & installed an M performance exhaust for the thing. Thing sounded incredible with it, even after it went kitty-less for DPs.





After selling the winter wheels that came with it, made it out just over $6k for the thing. Given this was still around peak covid pricing I thought I made out pretty well. Worst case, even if the motor let go, I figured you can find N54 long blocks anywhere from roughly $800-2k. Given the chassis was rust free and in great shape, figured it'd still be a good deal.

Now initially, the idealistic plan with this thing was just to enjoy my first manual car for spirited weekend drives, and eventually have some fun with it on track. Learn how to drive well with 3 pedals, and upgrade stuff as it broke or wore out for better or more capable parts (when the budget allowed), eventually amassing to more of a clubsport build. Still street-able, but affordable and fun to take to the track given its narrow body limitations of tires, and relatively cheap consumables coming with free replacements from FCP. That and knowing I could get plenty scrappy digging for deals, used parts, and doing all the work myself having gone through just about everything n54 and suspension related with my 335i. Anything else, I figured I'd just learn and figure out along the way in the name of some good self sufficient fun, just going slow and enjoying the process.

Well, let's just say, I got that bug again, and scope creep is one hell of a phenomenon.

Got right to work, and pretty much straight away dropped the subframe, tore out any and all rubber bushings for spherical or solid replacements, and existing monoball stuff was refreshed with new bits.





Despite having the 2 piece revshift aluminum RSFB's, the fronts were a nightmare to try to hammer in until I went to town cleaning up the inner bush mating surface of the subframe with Dremel sanding wheels. Even big wire wheels on my drills didn't cut through the midwestern corrosion, but eventually got the job done with a celebratory bird flip.





Funny enough, this eventually got me kicked out of being able to do any car work in the building's garage I was living in at the time. Guess management wasn't too happy that I woke up a neighbor at 1am trying to hammer in that front mount. Oops lol.

Only thing I decided to keep cushy was opting for whiteline poly diff mounts, but even after fabbing up my own diff brace down the line, I found that I hollowed those out creating an uncomfortable amount of drivetrain lash and wheel hop, and would eventually swap them out for a set of AKG motorsport 75D (essentially solid, with the race car diff whine to pair).

Replaced the blown shock with a set of ST XTA coilovers all around with stiffer rear swift springs, alongside eibach e82 specific bars, and adjustable rod type camber & toe arms with monoballs that I got every arm with 2 sets of replacements each for just over $100 shipped striking a deal with some Alibaba dealer. Sticking to the ethos of keeping it scrappy here. Little bit heavier, and sure, not SPL quality, but given the price, I figured I could chew through them and still be in a better spot than balling out right away on the high end stuff. Achieves the same end goal of removing any deflection, and happy to report the same one's I initially installed are still in there going strong without any play.





Within a few more weeks, fun parts started to arrive, having scoured the forum classifieds & FB marketplace for any juicy deals I could find. Found an RTD chassis mounted short shifter for cheap, and scored a set of SPL front LCA's on the low as well. Did some light cosmetic stuff like wrapping some of the trim pieces in alcantra, and swapping some of the cluster lights & needles, trying to slow down a bit and knock out some low hanging easy / quick mods.






Found a cheap set of e46 comp rep wheels locally that fit pretty decent and gave a good temporary look to the thing, and was pretty happy just enjoying the thing as it sat for some time.





From here, pretty much had my fun enjoying it on the street and becoming proficient using all 4 limbs at the same time. Having spent the last two years taking sim racing very seriously putting in an ungodly amount of seat time into my rig, I knew the next step for the car would getting it ready for its first track outing seeing if I could take what I've learned to real life. Which ended up being a fun process, but a bit more than I'd bargain for thinking it'd handle the abuse in the temps department. Anyone who's tracked an N54 knows, you definitely gotta have your thermal management in check, especially if you're thinking you'll make it long out there beyond stock boost.








After swapping the now slipping stock clutch for spec S2+ & steel SMFW (good fun doing this for the first time getting that top bell housing bolt out), refreshing everything around it along the way, building a diff on the cheap, somehow managing to get a 30row oil cooler in the passenger wheel well (spoiler, def didn't fit great, and for sure needed the duals that I'd eventually make a kit from scratch), some fresh 245 square Nexen Sport R's I found second hand but unused for dirt cheap, a CSF rad filled with distilled water + water wetter, and then a set of DTC60 pads all around with some trick titanium shims up front, we were ready for our first track day with SCCA out at Autobahn country club with the thing.



The first of many alignments I'd do myself — since improved the methods and processes quite a bit from humble beginnings.


It held up decent for the first day, but couldn't handle more than 3-5 hard laps before getting banished to limp mode purgatory. Boo. High & swampy ambient temps didn't help, nor did the god awful understeer from not really having the kinematics setup right just yet.





Learning to be fast and making a lot of mistakes in the sim racing prepped GT3/4 cars on slicks all day is good fun, and I think a very useful & cost effective means to learning how to drive on the limit. However, I'd come to learn that in the real world with our own machines, it's a lot more about driving around the car and it's own unique aspects & attributes than it really is your own limits as a driver. I definitely know how I want the car to drive, and to suit my own driving style, but the dynamic of learning how to extract the most of what you got when it's far from what you want it to do, is a completely different flow. This would kick start a whole new venture over the next year really getting into the importance of setup, and how getting down and dirty with the fine tuning of all the parts we now had the capability to adjust would have an effect on how we could get the car to dance right.

...

Gonna skip ahead a bit here in interest of not dropping roughly a year and a half of updates into what's already a pretty lengthy post, but hopefully you got the idea just how full potato I ended up going with the thing right off the jump. Pretty much sets up how the rest of its progression would evolve to current time.

Thinking the plan will be to drop occasional posts of the bigger things that netted significant changes for me, leading up to more current happenings in effort to kinda keep a log / journal of the build as it progresses.

Probably not the most orthodox path to starting a build thread, but I think this is better than just keeping it in the dark and not putting anything out about it.

Going to drop some photos below of where ol' girl currently stands, as well as the current build sheet / list of stuff done to it. Probably forgetting a thing or two but will keep it updated as time goes on/things come to mind.











Current Build Sheet as of 2.14.25

Interior / Safety:
Vac Motorsport single piece DOM half cage
OMP Steering wheel w/ 2” Spacers & NRG Forged Quick Release
Sparco QRT R FIA Bucket Seats
Schroth 6pt Cam-Lock FIA Rated Harnesses
Macht Schnell Floor Mounts
VAC Motorsport Anti Sub Mount Bracket
VAC Motorsport Lap Belt Mounts
Sparco Seat Brackets & Sliders
Interior fully stripped rearward of B pillars
Custom fab’d battery tray delete panel
Deka EXT30L Battery
Amerex 2.5lb Dry Chem Fire Extinguisher
Racebox Pro Predictive Lap Timer
Android Tablet for MHD data readout & logging

Chassis/Aero/Body:
Full OEM BMW 1M Widebody (rear fiberglass molded flares)
Trackspec M3 Hood Louvre Set
N15 Design Fender Louvres
M3 Steering Rack
Revshift 2pc Solid Aluminum Rear Subframe Bushings
APR GT 250 64” 2D Element w/ 14” risers & custom fabricated baseplates attached with rivnuts to trunk lid
Custom Chassis mounted 10mm Alumalite based splitter w/ diffuser tunnels, air dam, & end plates
M3 Strut Tower Brace Retrofit

Suspension:
Custom Spec’d & valved Fortune auto 510 w/ swift 8kg F 16kg R
F8x Front Spindles
SPL Front Lower Control Arms
SPL Tie Rods
M3 Front Tension Arms w/ AKG Spherical bushings
Eibach Front & Rear Swaybars & Swaybar Bushings
Spherical Rod Style Adjustable Rear Upper Control Arms (upper Front & upper Rear)
Spherical Rod Style Adjustable Rear Toe Arms
ECS Solid Trailing Arms
M3 Rear Lower Camber Link / Spring Carrier
Trailing Arms Bushings converted to Spherical Bushing
Powerflex Black Race Lower Control Arm to Chassis Bushings
SPL Eccentric Lockout kit

Brakes:
F8X Brembo 4piston front calipers
034 Motorsport F8X 380mm front rotors
Girodisk F8X front Titanium backing shims
Hawk DTC 70/60 Pads Front/Rear
997 GT3 Front Brake Scoops
M performance rear rotors
ECS Steel Braided lines
Motul RBF600

Motor:
MHD OTS Stage 2+ E40 Tune
VRSF 7.5” HD 1K Race Intercooler
VRSF 3” Catless Downpipes
Aluminum Charge Pipe w/ Genuine Tial BOV
Hybrid Precision Raceworks / VRSF 2” Inlet setup - Relocated front, stock location rear.
Index 12 injectors
Walboro 535 low pressure fuel pump
N55 Midpipe
Becker Performance 1M quad axleback (street) straight pipe turndown tip for track
CSF Racing Radiator
Custom Dual 25 row Oil cooler with Custom AN Lines + shrouding
Mishimoro AN line Tstat Line converter
FTP 184º Oil Cooler Tstat
RB External PCV Setup with headports tapped & plugged + dual catch cans

Transmission / Drivetrain:
RTD V3 Carbon Chassis mounted Shifter
Spec Stage 2+ Clutch + Billet Steel SMFW
3.46 Gear Ratio 188L Pumpkin with Mfactory helical LSD
Turner Solid Aluminum Engine mounts
Turner Solid Aluminum Trans Mounts
JXB Center Support Bearing Carrier
AKG 75D Diff Bushings

Wheels / Tires
Titan7 T-M20 Forged Motorsport Wheels 18x10 ET25
Kuhmo v730 275/35/18 Square

[MikeroniNChz]

That's a heck of a transformation in 2 years! Was there any single modification that made the most difference? How did handling improve with 1m conversion and being able to run 18x10?

[thisisluka]

Originally Posted by MikeroniNChz

That's a heck of a transformation in 2 years! Was there any single modification that made the most difference? How did handling improve with 1m conversion and being able to run 18x10?

She's come quite a way for sure, it's been a fun learning process building the thing from the ground up.

Tough to single out a mod that netted the most gain, really has been a sum of all its parts.

Probably my top 3 in order would be the buckets/cage/harnesses/steering wheel & extender (technically one mod since they all need to be done at the same time for safety). Not getting tossed around, while being in a comfortable seating position & in control is huge and something I think many overlook.

Tied for second / third place would be the custom spec'd Fortune Auto 510's and the f8x front spindles.

The control and feel the 510's offered over the ST's are in a different league. Ability to really feel the tuning you can do, to both rebound & compression to effect how the chassis dances, all the way to the sophistication with their dampening characteristics both over road imperfections on street, to jumping curbs on track, without getting out of shape, was a noticeable difference.

F8x spindles also netted a noticeable change to understeer given the change in Ackerman angle & dynamic camber differences once you get the wider wheels/tires on there. With the stock e8x spindles going to the 1M spec front width wheels & tires, it didn't feel as huge of a difference as I would have wanted to getting the front end to feel as pointy as I'd like, but the f8x spindles helped a healthy amount to get closer. The rest is largely due to setup, balancing out bars, spring rates, and alignment. Something I'm really keen to test this season is how it feels pulling out the Eibach front bar for stock, instead vouching for higher front spring rate, as I think the Eibach product has way too stiff of a front bar relative to the still pretty noodle-y looking rear from them. Have a feeling this will net the biggest change to getting the front end to be as direct as I'd like, otherwise it'll likely be a move to e9M F/R bars.

[tracer bullet]

This is awesome, of course. Congrats on the car, all the work done, the experience you've gained, and for sharing it!