Cristian's Silber Grau Metallic '06 ZCP Manual CSLed Werwölfe

[CrisSilberGrau]

Some foreshadowing, still winter here.

[CrisSilberGrau]

A lot has happened since the Yurkan 6 point cage install. Probably a top 5 mod of all time for this car, the rear and is literally paper mache from factory. Im gonna say regardless of your use case this is something everyone should do (options for fold down seats or not, modular or not as well). I can liken the difference to going from oem seats to nogaro buckets, it's that apparent and that good. If you track do this instead of a bolt in cage.

In the quest to make this car more capable on track the other weak point was the RB brakes, I had out grown them and managed to get a PFC ZR45 kit from a good buddy. The pros is increased brake feel, imo brake thermal capacity, caliper rigidity and pad depth. Also lost a few pounds front and rear, the RB setup was still surprisingly light. PFC rotors are V3 and the rear passenger clunks like an Indian tukuk. I think the specific rotor hat may be tired all the other rotors are quiet.

Braking performance at the track is considerably improved. Above all consistency in pedal feel, brake pedal went up. Overall very happy. Using PFC11 pads and Castrol SRF.

The next big performance mod came to the rear axle. The Fat Cat Ultimate Stage 3 was an amazing addition with 400lbs / 784lbs rear springs. I wanted to correct the rear geometry to allow the rear ride height to drop more as well as the front (but not as drastic). Enter MRT full rear bushing set and and front outer tie rod ends. Rear knuckle bushings (45mm) were eccentric as well as the rtab (60mm) bushings. RTABs were accompanied with anti dive RTAB mount and I think this is the main reason for the drastically increased grip. Install is a giant pain, you need special tools, pullers pushers etc and at least two pairs of hands. For the front you will need to use E90 inner tie rods as they are longer, went with the +\-20mm variant.

Track mechanical grip is drastically increased. This is apparent everywhere. At Mosport GP it felt like I was driving a cup car without a wing. On 265 RE71RS managed a solid 1:33.2 and can probably dip into the high 31s with more seat time and setup learning. There's a lot left in the car but the weak links are the rear axles, oem 270km old diff, and transmission that now doesn't like to go into certain gears at certain times. The goal is to get this car on 200tw tires to hit 1:29.xx on Mosport without aero and the interior trim level of just buckets and rear seat delete. Lofty goal since Mosport is a very high average speed track, but I'm pretty confident I can get there.

I also drive the car on the street, personally I love it, since the dream was always to distill the essence of the chassis and the engine to as raw a degree as I can bare. And the most recent mods particularly the bushings may be where I stop in terms of harshness, it can be a bit too much at times.

TO DO List before year end ideally:

• Construct a light but aesthetic rear seat delete
• installe CSL door panels and delete door side airbags
• replace the rear window trim FFS
• Unlikely: Radium catchcan, Radium fuel rail, Bosch ev14 550cc injectors install. Would require a tune and the funds for this year dried up March 10th.

PS: will post Pics later

[karter16]

A lot has happened since the Yurkan 6 point cage install. Probably a top 5 mod of all time for this car, the rear and is literally paper mache from factory. Im gonna say regardless of your use case this is something everyone should do (options for fold down seats or not, modular or not as well). I can liken the difference to going from oem seats to nogaro buckets, it's that apparent and that good. If you track do this instead of a bolt in cage.

My exact experience as well. The difference the 6 point brace makes is insane. I don't track my car but still the difference even driving on the road is huge. I appreciate not everyone can stomach having a brace taking up trunk space, but imho anyone who can should have this. Definitely in my top 5 mods too.


Sent from my iPhone using Tapatalk

[Gt4]

Cool, I was considering building a rear brace myself but now you convinced me! I have CMP topside front/rear so I will use the threaded inserts in those beams

[CrisSilberGrau]

Long Time Update:

TLDR:

• Reached a low 1:31.3xx at Mosport on old new 2018 TrofeoR 265/35/18 square.
• After the last update, there were quite a few more track days but only 3 at Mosport. The 1st of the 3 was the an imrpovement on the same cycled RE71RS' to a 1:32.6xx, 2/3 day rained, 3/3 the last possible session of the day Oct 13 @ 4:00pm I got a clear enough track to exploit all the mods done to the car (there was a lot).

Pics to follow in subsequent posts, this is more of a journal. The last post with all the MRT changes and brakes, thats exactly how I took the car to the 1st of 3 more days at Mosport. In, hindsight it was one of the best days of the whole season and could have been better if I prepared the car a bit more.

Managed a 1:32.6xx and the car felt great overall. No issues. I also got to drive my very good friend's E46 M3 Track car (welded half cage, halo seats, yurkan, 288/280, CSL, PWR, AP 5000R, KW V3 Comp, Bimmerworld exhaust wing custom splitter, fresh 3.3L rebuild with Mahle 11.6 pistons etc. CRS 275 square). Probably the best driving car on track I've ever experienced, managed a 1:29.8xx in it on the same day with a passenger and 7 laps in it. I was great to drive and easy to draw the similarities to mine. The overall chassis rigidity was the main takeaway. Aero is also nice.

For those that dont know, Mosport is an old school track with lots of history and pedigree. Highest average speed track in NA. Any road car that can hit 1m:2x.xx is a very fast time that usually needs turbo power and slicks. To reach my goal of a 1:2x laptime with 200tw tires in a car thats 20 years old (26 depending on how you look at it) is no small feat. You need to know what you're doing because if things go wrong they go wrong at 100mph.

For the last 2 days there I decided to make a big push to reach that goal. On short notice I decided to do the head gasket on my car, no reason other than 165k miles. It always pulled strong (if anything was a bit "off" since the last time it saw a dyno with the Schrick issues). Everything replaced with Genuine BMW parts and the head was slightly shaved maybe gaining a few points of compression back after the static loss with the CATCAMS 280/272s. First few drives butt dyno was optimistic above 6k, a bit of a sharper growl there too, anyway S54 goated just feels good I did it. There were no issues with the HG, pistons were quite caked in carbon and I did my best to scrape that away with wd40 and some power tool bits. Then bought an over the counter honing bit and with help was careful to restore some hatching to the bores as they were mirror like in cyl 234, worked them all ofc. Valve adjustment, buttoned up. Car felt mint.

Decided to go with new tires as the REs were spent on the front. Enter brand new 2018 TrofeoR 265s, ultra wide would rub on the same spacer 15mm i used with the REs. They were about 800$ cheaper through a contact than the competing CRS/RE.

Diff being 165k original, had a buddy with a Z4M rebuild unit and 3.91s motorsport gears available and got that for a very good deal.

Then coincidentally came up on a silver gray oem trunk with a Ridgeline GT4 wing and decided to give it a try. Aero wise this is as far as id ever go, old school Ring Tool look is as far as I'd take it. To complement the rear, installed the MK rennsport technik GT4 lip I've had sitting for 2 years on the OEM bumper. Cut out the fog light recepticle and fitted bimmerworld CF intakes. Routed my own hoses to brakes and CSL intake.

Found a very competent motorsport alignment tech and went for a full evaluation and alignment. I'll try find pics of the alignment as it sat on his hub alignment tools, some wild values I drove with and it supported my concerns with the car not being as willing to change direction at certain parts of the track. I had asked for some specific values at the previous alignment shop after I installed the MRT kit (namely camber -3.8/-2.6 and toe -.12/.10 ) the rig audited the car at camber F -2.4/2.6 R -2.4/-1.8 toe F -.10 total vs -.24 total requested R .20. After a laugh and spit balling geometry, settled on the below.

Camber Front : -3.3deg
Camber Rear: -3.5deg
Toe Front: -3mm
Toe Rear: 2mm
Rake F to R: 10mm (this was above 20 on audit)
Corner Balanced with me in it.

The 2/3 day at Mosport was a wash literally, rained. However one of the coil packs (bosch replaced in 2019 when i got the car) gave out, was lucky as some friends were there with a track car on slicks and they gave a coil pack. Replaced for 3/3 all six with Eldor.

3/3 Oct 13 - 2025 Perry Autolaval Mosport track day

Started out very cold. In the advanced group there were the big bois with race cars 992 GT3 Cup (2x) 718 GT4 RS Clubsport (3x) and a load of very fast road. However, the attendance was mostly from Quebec so not their home track. Had to pass some of the 718 race cars as they were not on pace with me and some of my track comrades. Felt good to pass race cars on slicks. There was little to no room to create a gap for a clean lap or to create rhythm the whole day until late in the afternoon.

Two 30 min sessions left at 3pm and 4 pm with the sun coming out and heating up the track it was the best time to set good lap times with the cold Oct air. At the 3pm session, I pass a slow 992.2 Carrera GTS in the middle of the track between turns 3/4 build a gap only to be passed into the braking zone of turn 8 the highest trap speed on the track, and potentially have my next few laps ruined. Made it a point to stay within a foot of the guys bumper (hindsight will never do that again). I must have distracted the driver, he over drove turn 10 and tank slapped into the wall on the font straight writing off the car in spectacular fashion. I could see it happening in slow motion and anticipated it easily, session done red flag opportunity gone.

Last session, lots of traffic, managed the best time early on. Trusted the little bit of aero into turn 4 and 8. The car felt very planted and I wasnt close to the limit. But it felt like seeing God anyway. Two cool down laps and went for another kill lap, was behind on the delta by 3 tenths going into turn 4, took more speed with the same planted feel and caught 5 tenths. But the extra speed into the compression and brake point of turn 5 caused an error, brake point missed and had to abort the lap. Best sectors of the whole day put the car at 1:30.3xx

I can disect the lap a bit more for those that care. It was a wild ride to get the car to this point in a single season. The to do list is almost the same as above still:

• CSL 1x1 door panels install
• F80 CF driveshaft
• Radium Fuel Rail/550cc Injectors/Retune
• NEW: full detent, spring etc, trans refresh

Ill only have funds for 1 at most 2 track days. Excited. I have a cup car for the road. The SS race shaves 12lbs off the SCZA, weighed it at 24lbs. Sounds glorious.

PS: TrofeoRs were really hard to get to grips with, the feel wasnt there, the REs were a lot better in terms of communication. However they produced lap time, dont know how much I can attribute that to though.