'06 ZCP Street Build - A Continuation

[SeñorEnglish]

I love the apex wheels swap

[dreamdrivedrift]

Inaugural road trip update, this marks version 1 of the car:
A good friend (Jay) flew into town and we made our way up the coast to near Eureka, CA joined by a few friends.
Rt 1 past Westport into Leggett is fantastic. Tight, technical, flowing 2nd-3rd gear turns with good pavement quality that seemingly never ends. Traffic tends to be sparse.
The road to Shelter Cove is a one way in one way out type road. Unfortunately the pavement quality is really lacking with a lot of pockmarks, potholes, and yumps. A little disappointing but it put the suspension through its paces.

This car RIPS and is a weapon. It road trips well, and is comfortable and quiet with the windows up and AC on. It's easy to drive on the highway minus the lack of cruise control. Windows down, revs above 3K, it's explosive and completely intoxicating. It's stable and despite a mild understeer balance at steady state, its attitude is easily adjustable on entry with the brakes or with a little lift mid corner. Rear end is easily provokable on throttle. The steering is quick and communicative. Very easy to drive. All my complaints about the MCS being rough to ride are gone. They are magic over rough roads, it handled the imperfect back roads better than a stock ND Miata (the performance package BRZ was still the king in this aspect). I like the soft rates for these roads (400/650). It flows with the big bumps and dips though the front end still rubs and I'll probably still explore bump stops for the MCS at some point. This is my first set of PS4S and they had pretty impressive grip levels for being a non-200TW tire. Great tire for this type of street-focused setup.

Of course the project is never over, but I am very happy with how much a few parts and tuning has turned this into fantastic street-focused / track-capable / road-trip / backroad-crushing all arounder.

[nyc951]

Love the build and it's very similar to how I'd want to upgrade mine. How does the MCS 1-way suspension feel in the real world?

[dreamdrivedrift]

Love the build and it's very similar to how I'd want to upgrade mine. How does the MCS 1-way suspension feel in the real world?

Pretty good once the car was raised up. More comfortable over most bumps and small imperfections than many stock suspensions. Wheel control over the small stuff is excellent and makes it seem like it’s not there - chassis and ride stays steady. Rides better than the modified Ohlins DFVs I have in my S2K. A little noisy but it’s not bad w rear seats up. Over large yumps and compressions it can still be more uncomfortable than a modern stock suspension car

[dreamdrivedrift]

It's been running well and getting quite a few miles. I must have said it before, but this car has such a broad dynamic range of ability and enjoyment, from airport runs to date nights to even a drift day. The suspension feels great with some damping adjustments. Initially was getting some on throttle understeer, but tightening up the front dampers helped to keep the front end planted under throttle. I am really enjoying driving the car.

Notable recent events:
-The car was recently reviewed on the Zygrene channel. It was reviewed against a friend's 1M. The video should be up within next couple weeks.
-I also took it to a skidpad/car control day - it is very reasonably balanced and easy to slide. So much fun.
-Destroyed a set of rear tires, 275s. I have since stepped down to 265s on a 9.5" wheel (now running 265/275 stagger and eventually will be 265 square), I felt the 275 turn in response on PS4S on a 9.5" wheel was too mushy.
-E88s sold to a fellow forum member Tbonem3
-Oil change disaster. The oil drain plug stripped on its way out. I almost had it towed to the shop since I’ve never repaired threads before, but decided just to fix it on my own. I used the Timesert 1215C kit which was designed for BMW oil pans. It requires drilling out the hole to a slightly larger size and then tapping the pan to insert a steel insert. You can then reuse the original bolt pitch/thread (I bought a new one). It was pretty nerve wracking being the first time, but was actually pretty easy especially since the oil strainer cover is right next to the oil pan bolt. I stuck a bunch of oily rags above the oil drain plug, used grease on the tap, and cleaned the bottom of the pan until my OCD was satisfied. Should have taken more pics, but the steel insert went in fine, holds oil, and should be stronger than the old aluminum threads since a Timesert is a threaded steel insert. Oil finally changed with Liquimoly 10W60 + Ceratec.

[dreamdrivedrift]

Memorialized. Hopefully I did the E46 M proud.

[cornerbalanced]

Memorialized. Hopefully I did the E46 M proud.

Was so happy to see him finally drive a properly setup E46! Seems like he enjoyed it more in the canyons than the 1M, that says a lot.

[Tbonem3]

Nice review!

[lcrain]

I watched Zygrene's review this morning. He seemed to really enjoy it. Two great M cars that seem similar on the surface but offer quite different experiences.

[dreamdrivedrift]

Updates for 2024:

This car has been a joy to drive. I am loving the breadth of capability of this car. The MCS suspension is phenomenal, the car literally rides better than my MK 7.5 Golf R on the I-680/I-880 which have horrendous road quality. The current setup is on 400F/650R paired with a Turner front sway on full soft and PS4S 265/275 at about -2.7 deg of camber all around. The car has poise and balance; a slight understeer balance at steady state, will do 4 wheel slides and oversteer with a lift or dab of brake mid corner. This car exhibits that hard-to-find attitude of being adjustable and predictable on the limit based on driver input.

The drivetrain is exhibiting a new tune from Bryson which has smoothened out the 1-3K response dramatically – it is much smoother than the prior HTE tune.

The chassis - CMP stage 2 front and rear subframe reinforcements were welded in and installed
Bimmerworld dual fuel pumps were put in as well. Fuel gauge doesn't read right and while starve issues have improved they're still there and will need to be re-evaluated in the future.

Overheating was a challenge this year. We went on a trip that involved going over Sonora pass, and at 7000ft under normal load (not pushing it) it started to overheat, water temps in the 220s-230s before I shut it down. Coincidentally another friend’s E46 M3 with a CSL airbox also died, and we thought it might have been tune/altitude related. The cars were fine once we got to lower altitude but it was clear they would not be able to it over the pass. We backtracked home to drop the cars off at home and pick up my Civic Type R to complete the trip.

While we initially thought this was tune related, it overheated again at its first track day at Laguna (sea level). I wasn’t able to get more than a lap at full chat before having to back off to let the car cool down. Had to short shift 6-6.5k to manage the heat. At this point it was clear the cooling system was the issue.

The cooling system had been redone last year, but I had opted to put in a CSF radiator at the time thinking it would be a more durable option than the OE radiator. Installing the CSF was a mistake that I learned after reading other posts on this forum with similar complaints. The CSF radiator was replaced with a genuine BMW radiator with 50/50 mix + water wetter.

Second track day was a full weekend at Thunderhill. The 5 mile course is one of my favorites across the country, they connect the east and west course together. The connector for east-to-west goes over a ridge, and is gorgeous in the green California winter. Saturday was the rainiest I’ve ever driven on track, with cars going off and sessions getting black flagged every 1-2 laps, but the rain was fun. Sunday was dry. The car performed flawlessly without any overheating at all. The PS4S were a great choice, these tires have grown on me and similar to the M3 have a wide breadth of capability. While everyone else was having trouble getting heat in their tires or dealing with standing rain, this tire delivered in the rain, and has pretty damn good grip in the dry too. I ran a 3:15 conservatively on the only clean lap I got all weekend which is 7 seconds faster than what I ran in my non-aero S2000 on RS4s a few years ago.

For 2025, my goal is just to drive more. 2024 was a busy year with work and I’m hoping to enjoy my cars a bit more frequently. The car is damn near perfect but I do have a new OEM CSL trunk sitting in my house waiting to be painted and installed…

[dreamdrivedrift]