Okay, I have attempted to compile the info I've learned from this thread, plus some info from other forums and other BMW folks. Here is a summary of what seems to be the usual preferred setup for a DS E46 BMW. These notes are somewhat specific to a ZHP car, but only as far as wheel size. Let me know if anything is incorrect or incomplete.
I'm personally on a budget (buying the car itself was a stretch), so I am not doing all these things. I'm just getting some used BMW wheels and Kumhos and doing an alignment. But perhaps I can eventually get some shocks and maybe exhaust too.
1. Wheels/Tires
· 245/35-18 Kumho V710 tires (or Hoosier A6 or BFG R1 or similar) on stock size wheels
(For Hoosiers start at 45psi front 35 psi rear. For Kumhos?)
o These cars are camber-challenged up front, and this may cause premature wear on the Hoosiers
· Some folks have had some success with 275’s or 285’s front/245’s rear
Wheel Options:
· BMW OEM Wheels
o Used 18" OEM wheels in good shape usually run ~ $800 per set
o Turner Motorsport has new OEM style 125 wheels for $220 each
§ These supposedly weigh ~25f/26r lbs.
o Style 32 may be the lightest OEM 18” wheel
§ Reportedly 20/21 lbs.
o Stock ZHP wheels are style 135, ~ 28/29 lbs.
· CCW custom lightweight wheels $2200 per set, if you have the funds
· Wheel notes:
o Stock ZHP wheel size is 18x8, ET47 front, 18x8.5 ET50 rear, 5x120 bolt pattern
o SSR GT2 wheels came in stock sizes, but no longer available
o No other standard aftermarket wheels available in the right sizes and offsets
o Can mix wheel brands front/rear to get the right sizes
o TRMotorsport makes a great 18x8.5 for the rear, 18.5 lbs, $300 ea.
o Most 18x8 wheels have +40mm offset, which is 0.7mm beyond legal limit.
§ Some folks machine off the 0.7mm extra to be legal
2. Alignment
· Max "slop" camber up front (probably around -1.2)
o Driving out the upper strut locator pins is legal per TSB
· About -1.5 degrees camber rear, less if you want the car to rotate more
· 0 toe all around
o or a little front toe-out to improve turn-in
o or a little rear toe-in to improve rear stability
3. Front swaybar
· H&R 27mm Front Swaybar
o H&R has good bushings and you can buy only the front bar instead of a set
· Ground Control or Turner Motorsport adjustable endlinks
o Ground Control look beefier and high tech, but Turner’s OEM-style ball joints with rubber boots would likely last longer
o Stock endlinks are probably fine
4. Shocks
· TC Kline double adjustable Konis (~$1600/set)
o Full rebound all around, compression: 8F, 6R
· For a budget, Koni single adjustables (~$800/set)
· Some use Koni singles up front and doubles rear
5. Brake pads
· Hawk HPS pads front, HP+ rear is a popular combo
· OEM pads work well, but may get some fade with multiple drivers on a hot day
6. Exhaust
· Catalytic converters are in the exhaust manifolds, so a header-back system is legal and can save a lot of weight
· Bimmerhaus offers a single 3” header-back exhaust that saves ~40 lbs and can use any muffler you want, but probably pretty loud on the street/highway. A Supertrapp would allow tuning for street and competition.
7. Other
· Schroth street harness or CG-lock to keep you in your seat.
o Optional bolt-in harness bar or connect Schroth to rear seatbelt anchors
· K&N drop-in air filter element? Any real benefit?