[RichardC300]

I’ve been thinking about what car to get for a project car/track car after I sell my M235i, and I keep coming back to an E90/E92 328i.

This build is so cool. Awesome car.

[RealJ22]

Originally Posted by RichardC300

I’ve been thinking about what car to get for a project car/track car after I sell my M235i, and I keep coming back to an E90/E92 328i.

This build is so cool. Awesome car.

Do it. I've had like 4 e9x and for some reason this cheap 328i I bought is one of my favorite vehicles yet. It's the last vehicle of its kind. You could technically keep them running forever.

[Minutes2Midnight]

It's update time, I reckon.

When I left you last, I was preparing for an SCCA Time Trial event at Road Atlanta, and it went great!...right up until a spectacular mechanical failure going into turn 10 in my last session. In the hardest braking zone on the track from 150+mph, from 5th gear down to 4th gear and then...the car wouldn't go into any gears! I had enough speed to coast into the hot pits and let the car cool down. Thankfully, the car would go into gear when the trans cooled down and I was able to limp the car home.

Teardown of the clutch revealed a failure of the 335is pressure plate. Our theory was that it failed because I used an unsprung friction disc with a single mass flywheel. The show must go on though, so the 335is clutch setup was ditched in favor of a ClutchMasters FX350 clutch kit which, aside from a heavier clutch pedal, is fantastic.



Aside from the clutch failing, I also learned that the 265/35/18 square setup was just slightly too big. I had to run a 10mm spacer for the tire to clear the front springs, and I had to raise the left front ride height to stop the tire from rubbing the fender. I also learned that I need a stiffer rear spring in the car. This was my first time hot lapping at Road Atlanta, and while the lap I set was good enough for second place in the Max1 class, I came to learn it wasn't very fast. I have since run a Lemons race at Road Atlanta and got enough seat time in awful conditions to feel like I can put down a much more respectable time in this car, so I look forward to the next track day at Road Atlanta!

[Minutes2Midnight]

At long last, the Quaife is in! On page 2 of this thread 5 years ago, I purchased a 3.73 diff from an auto 328 and promptly threw it on a shelf with half a dozen other unfinished projects. Well last year, I finally got around to it! With the help of a friend, I removed my 3.23 open diff from the car, swapped the LSD into the 3.73 rear end using new bearings sourced from MFactory and a giant pair of snap ring pliers, and mounted the diff back into the car using Turner Delrin diff bushings, which were the same ones found on the E9x Grand Am racecars. I also used the finned diff cover from a 5 series, part number 33117516280. The leftmost fin was trimmed for exhaust clearance.

[Minutes2Midnight]

Latest exterior mods:

I swapped out my big 'ol manual folding LCI mirrors for a set of pre-LCI power folding mirrors. I went through 4+ Le Mans blue mirror caps and all of them had clearcoat failure. I like the way the smaller mirrors look, and power folding functionality is awesome. This retrofit requires also buying the mirror switch panel with the power folding button and coding your car to recognize the new panel. Icing on the cake is a set of OEM carbon fiber mirror caps I found for a steal on FB marketplace.





The Grand Am wing got a new look!

It has been paint matched blue as long as I've owned it, but I felt like it was a shame to not show off the fact that it's a carbon fiber part. So, here's the new look! Paint matched on top, exposed carbon underneath.









New Diffuser! I felt the stock M Sport diffuser was a bit weak with the aggressive wing, so I bought this diffuser from a vendor who I later learned was banned from the forum for credit card fraud. So yeah, thankfully I got my diffuser lol

Before:



After:



Glamor Shot

[Minutes2Midnight]

Interior Mods

I retrofitted an E89 Z4 steering wheel into my E92. I bought a used standard Z4 wheel on eBay, sent it out to Royal Steering Wheels in the UK for reupholstery. I asked them to reupholster the wheel with perforated leather at 9 and 3, just like the E9x M Sport steering wheel, but with M tricolor stitching. I sourced the M Sport trim pieces from a local dealership who had them in stock, and I think it came out great. I love the round airbag and I think this wheel is sort of in between the E9x and F3x steering wheel designs. Personally, I think it goes really well with the rest of the interior.

Sourcing an airbag was the hardest part of this swap, since most wrecking yards seem to want $800+ for them, if you can even find one. This is a direct swap as long as you use the correct type of airbag for your region, which in my case was a US spec dual stage airbag.









I also traded out my tired saddle brown center console lid for a shiny new one with a split armrest.

[Minutes2Midnight]

Lastly, here's the latest performance stuff.

The production version of the StageFP intercooler manifold has come out now, and the performance is much improved over the prototype unit I ran for several years, although it looks a little stealthier being black now instead of polished aluminum. With a new phenolic spacer to keep heat transfer down between the cylinder head and the intercooler, the intake air temps stay even cooler on track than ever before. The injectors were upgraded further from the Porsche GT2 injectors up to 1000cc injectors in hopes of chasing big power figures, and the fuel pump has been upgraded to a Precision Raceworks dual pump setup, with the second fuel pump on a Hobbs switch that kicks on over 10psi boost pressure. The fuel sending unit was also upgraded to a PRW pressure regulator. The stock EKP has been upgraded to a Speedsty EKPM delete to eliminate the stock EKP as a failure point.

Attempts were made to make more power out of the setup, and we did finally hit 500 with a 2.8 inch pulley last year at nearly 20psi.



However, Bob at StageFP mentioned he noted that the RPMs were unstable over 7k RPM. It could be that my supercharger is in need of a refresh, or that the Vortech itself is just too near its upper RPM limit. Whatever the case may be, we have decided to keep it at the previous level (mid 460s at 12psi) due to the proven track record and how well it's been running reliably. This weekend, the car will get its Porsche injectors back, since the chosen 1000cc injectors have been slightly problematic due to a different spray pattern causing difficulty dialing in the tune with regard to daily drivability. I'm very happy with the speed the car currently has, so I'd rather adjust my focus to spending money on track events and consumables rather than endlessly chasing a number on the dyno.





As of the time of writing this, I've put almost 53,000 miles on the supercharger, and this N52 has been as reliable as any other N52 despite being put through the wringer. Almost unbelievably, the last Blackstone oil analysis reported less wear than the average N52. I did 3 road trips from NC to Florida last year, between 1k to 2k miles each trip, and it never let me down once. BMW truly cooked when they made the N52.

[styast]

Love watching this build develop, especially those mirrors!

Did pre-lci mirrors come with the glossy shadowline finish? I haven't seen them before.

[Minutes2Midnight]

Originally Posted by styast

Love watching this build develop, especially those mirrors!

Did pre-lci mirrors come with the glossy shadowline finish? I haven't seen them before.

Thanks! From my understanding, the mirrors from M-sport equipped cars have a gloss black base. I got them on eBay and they didn't cost me much at all.

[7XEN]

Are you running on stock pistons and rods?

[Minutes2Midnight]

Originally Posted by 7XEN

Are you running on stock pistons and rods?

Yes, still stock motor at this point.

[Minutes2Midnight]

It's time for my annual update. Should be a pretty good one since it was a particularly expensive year owning the world's most expensive 328i.



*Record scratch* *Freeze frame* Yep, that's me. You're probably wondering how I got here.

During a Track Night in America event at Charlotte last August, I experienced a pressure plate failure that split the bellhousing clean off the stock GS6-17BG transmission. The failure happened while waiting for a point by from a vintage 911 racecar with a Huracan Super Trofeo Evo behind me, so it died doing what it loved and doing more than the engineers at BMW ever imagined it would.

The good news is that the great folks at EuroEnvy replaced the stock N52 transmission with a GS6-53BZ from an N54 powered 335i. The new ZF manual shifts way smoother than the old Getrag ever did, and the gear ratios are much better, with 6th now being a more usable gear. This swap involved modifying a bolt hole at the top of the bellhousing and cobbling together a custom driveshaft solution using parts from a Lexus GS and N55 driveshaft.

My takeaway from this failure is that you should avoid using a single mass flywheel with your N52. I have seen and heard about many transmission failures across various aftermarket clutch and flywheel setups since mine failed, and the only constant across them all is the use of a single mass flywheel. DON'T use a Valeo SMF or a JB Flywheel on your N52. Mine lasted about 12k miles before failure, but I experienced two pressure plate failures in that time, one of them destroying the transmission. Using a lightweight single mass flywheel just isn't worth any potential benefit given the number of clutch failures I've seen.

See the devastation below.













The car was great before that, though! Intercooler is still crushing it. 115-120 degree IATs on a 95 degree day.

[Minutes2Midnight]

The most exciting project for the car in the past year (and probably the greatest part of the car now) is the carbon fiber M3 roof swap. This is a project I always wanted to undertake (See comment #22 at the bottom of page 1 in this thread), but I didn't have the skillset or the bravery of the great Biginboca, who DIY'd this swap and documented the process in great detail many years ago. With the help of fellow supercharged N52 brother Dolan, and his many years of experience working at his family's body shop, this dream was finally able to come true.

We'll start with the end product, because that's the prettiest part and short form video content has all but killed our attention spans. You should definitely see this part.









Note the distinct lack of sunroof. That's the good stuff.

Things started to come together last summer when I found an extremely clean M3 roof cut on eBay listed by a dismantler who was about an hour and a half from home. I borrowed my dad's pickup truck, and drove down to pick it up. Unfortunately, as seen in the previous post, my transmission broke clean in half soon after buying the roof cut, so the project was shelved. Once I was back up and running, I took a step back and decided I wanted to start getting my car in better shape cosmetically. At 15 years old, the car is showing its age. The clearcoat on the roof was beginning to fail and the headliner was starting to sag as a result of years parked outside earlier in the car's life. To add insult to injury, a rock put a quarter sized chip in my windshield on my commute to work. With those three things in mind, the only logical conclusion when you have an M3 roof cut sitting in storage would be to swap the roof, the windshield, and the headliner at the same time. This is 'boy math', and it's about efficiency. Getting three birds stoned at once. It just makes sense.

As far as roof cuts go, this example was as good as it gets. Minimal yellowing of the gel coat at the outer edges and no failures or scratches in the clearcoat. It's possible that this roof was re-cleared previously. I had searched for one of these roof cuts for many years, and most of the ones that come up for sale are in rough shape, with the selection only getting worse as M3s get older.



I actually managed to track down the M3 that donated its roof and several other slicktop related components. To the owner of this M3, my condolences. I hope that you'll get some joy from many parts of your car living on.



The first step of this process is separating the carbon fiber panel from the roof rails of the donor car. The carbon panel is bonded to the roof rails using a bonding agent that hardens like cement, so the only option is to cut it free. Slowly. The front and rear edges where the roof panel meets the sunroof didn't prove as difficult as the sides, where you will run into difficulty accessing the surface where the panels are bonded together from the top side. Thankfully, Dolan is brilliant and discovered that he could cut off the outer shell of the bodywork to give easier access to continue separating the roof carefully with a chisel.





After several hours of chiseling, you should have something that looks like this:



With the roof panel separated and ready to go on the car, the next step was to remove the front and rear windshields, headliner, pillars, and sunroof assembly from the car.



Sunroof: Now you see me...



Now you don't!


The next step was removing the old metal roof. The documented process for doing so is to drill out about 90 spot welds around the perimeter of the roof. Instead of doing that, Dolan cut off only the outer painted metal layer of the roof, essentially just removing the outer roof skin and preserving the inner bracing of the roof. This decision was made to preserve the structural integrity of the metal on top of the fact that the existing metal structure of the roof has about three times as many contact points with the roof rails and is more substantial than the M3 roof cross bow. So done this way, it's less structurally compromised and retains more factory metal, at the cost of a few extra pounds.









This does mean that the car still has a sunroof hole, so Dolan modified the sound deadening on the carbon roof panel to accommodate it.



This was a tough judgement call, but I feel like the blue fin looks better. If the car was any other color, I'd probably go with black.



After prepping the mounting surface, the carbon roof panel was clamped to the roof and allowed to cure.





Once the roof had cured, windshields were re-installed with fresh weather stripping. After that, Dolan wet sanded and polished the roof to perfection.









The roof has been wrapped in Stek PPF in hopes of keeping any gel coat yellowing to a minimum going forward.

Fun fact: Your radio and central locking are tied to a matrix in your back glass that acts as an antenna! I thought the sharkfin on the donor car might have been broken when these didn't work...until they magically were fixed when the glass was reinstalled!

Still working on finishing the headliner, but I'm beyond thrilled with how the roof turned out, and am eternally grateful to Dolan for undertaking this project. Seriously, he did this from start to finish in 3 days.