The nice man at Bertini has written this guide for buying a BMW Z3. use it to buy a Z3 and then rebody it as a Z300S which looks much nicer
BMW Z3 and Z3M Buyers Guide
BMW Z3 1996-2002 Assembled in South Carolina USA
1.8 118 bhp 10.1 secs 1295 kg (1999-2002)
1.9 140 bhp 9.2 secs 1275 kg (1996-1999)
2.0 150 bhp 8.6 secs 1345 kg (1999-2002)
2.2 170 bhp 7.6 secs 1345 kg (2000-2002)
2.8 193 bhp 6.7 secs 1360 kg (1997-2000)
3.0 231 bhp 5.8 secs 1360 kg (2000-2002)
3.2 321 bhp 5.1 secs 1450 kg (1998-2002)
(2.3, 2.5 units were used in the USA)
(4 speed autos were available - these are slightly heavier and slower than the 5 speed manuals)
4 pots are a little under powered but are lighter but can be supercharged along with the six cylinder cars
2.2, 2.8 and 3.0 engines offer an exciting drive
3.2M engines are FAST and FUN but can be a handful in the wet and most don't have traction control
2.8s had wider rear wings and axles
2000 Facelift changed:
all models had wider rear wings and axles
remote central locking
headlining in hood
rear light / boot shape
wider rear arches and bumps over the wheels
some had clear lenses to headlights and indicators
chrome headlight rings
redesigned boot and boot brake light
DSC dynamic stability control replaced ASC traction control
a few interior modifications
Z3Ms
they have the s50 engine with 321 bhp (post 2000 cars were given the s54 engine with 325 bhp)
they share the same rear wings as the 2.8 wide-body but have a shorter rear axle and run rear wheels with a crazy low offset.
most Z3m's do not have traction control like many of the other six cylinder Z3's. (post 2000 models do have TCS)
all Z3M's have a LSD - these were an option on the Z3's
they benefit from uprated suspension, bushes and chassis
(this reduces the rear end droop experienced under acceleration on the higher power Z3s)
the Z3m has a colour coded interior dash
Common problems and things to look out for:
Generally the Z3 is an excellent car with great reliability!.... but look out for:
rotten sills, mini front wings, rear wings and lock on rear boot
Vanos problems characterised usually by loss of power at low revs and a funny sound for the front of the engine. (Mr Vanos can help repair these)
rear cross member and boot floor spot welds coming loose due to flex from the diff in the Z3M, 3.0 and 2.8 - check the boot floor for broken spot welds
electric hoods which are common on the higher spec. cars can often be temperamental
bonnet release mechanism often stick and need to be kept greased
each electric seat uses 2 motors. these can sometimes fail, also the rail bushes can become worn - check the seats in all directions
the clips on the side of each seat that funnel the seatbelts often brake
The wing mirrors can be affected by corrosion
Water/condensation in the boot - often caused by faulty weather gaskets
Check roof for signs of water penetration - if leaking then it is often just the hooks that need tightening
rear plastic windows on the hood is difficult to replace - but there is usually a crease along the window this is a common unavoidable problem
check for accident damage, resprays and panel gaps
BMW engines are usually sound if well maintained with a good service history
(however viscous coupling and the water pump are well worth looking at changing around 80,000 miles along with the guibo/flex disc)
Bushes tend to wear also especially the top mounts - this can be a good opportunity to install a polybush kit.
Best Modifications:
Bilstein or Eibach shocks and progressive lowering springs
Poly bush kit
Butt Strut system (ok with a lowered Z3 but clearance can be an issue with a lowered Z3M)
Braided clutch hose on z3m
induction kit (simota carbon airbox comes recommended)
reinforcement to the rear crossmember
(this mounts the rear diff - Randy Forbes USA do a kit)
twin ear rear diff
Price guide (UK Summer 2014)
The prices change a lot depending on the time of year and the quality of the car.
1.8 and 1.9 cars can be as cheap as £1500 - but a nice low mileage example can be close to £3000
2.2, 2.8 and 3.0 cars seem to start at £2500 and rise to up to £4500 for very well kept examples with low miles.
The Z3Ms can range between £6000 and £10,000 depending on the condition.
Full thread with more aDVICE HERE : http://zroadster.org/threads/z3-and-z3m-buyers-guide-for-bertini-gt25.4910/
5 Jun 2014, 7:27am