Z3 and Z3M Buyers Guide for Bertini GT25

Anthony Cherry

Zorg Guru (I)
3rd Party Trader
Nov 20, 2013
I am putting together a simple buyers guide for the Z3 and Z3M for my Bertini GT25 website and for an upcoming issue of one of the Kit Car magazines.

I have trawled the forums, Wiki, Parkers and used my personal experience of the 5 x Z3's I have owned to put this together so far.
But i would really appreciate any input to obvious mistakes i have made and and additions to the things to look out for when buying a Z3 and which are the best models to own.

Also any favourite modifications would really help for the guide.
here is what i have so far: - i will edit as suggestions are made

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

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.

Wheels and Wheel options
BMW Z3's came with 16 or 17 inch wheels. 18 and 19 inch will fit with lower profile tyres.
Avoid the run-flat tyres that come on many second hand sets of BMW wheels
BMW Z3s had 5x120 PCD with 72.5 centre core
Z3 & Z3M have a front ET of 41
widebody and facelift Z3's have a rear ET 37
slimmer body Z3's have a rear ET of 41
while Z3M an ET of 8
However as standard the Z3 wheels did not 'fill the arches' well so 10mm hubcentric wheel spacers enhance to look of the standard wheels

Wheels for the Bertini GT25
The Bertini front and rear width is the same as the Z3M and wide-body 2.8, so all wheels designed for a Z3 will fit the Bertini
Most BMW wheels will fit – but wheel spacers may be required
(Z4 108's on the blue Bertini have 25mm rear spacers and 15mm front spacers)
(BMW style 32 18" deep dish alloys (7 series) on the Z3M Bertini also use 25mm rear spacers)
(BMW style 32 18" deep dish alloys (7 series) on the Z3 Bertini do not need any spacers)
(BMW style 32 18" non deep dish alloys (3 series) require 25mm spacers on the rear and 15mm spacers on the front on the Z3 based Bertini)

Tips for buying a Z3 or Z3M for converting to a Bertini GT25
Ensure you buy the car you want with the engine you want.
(The small premium you pay for a facelift or bigger engine may be worth the longterm investment)
Ensuring the retained features of the car are in good condition can save you lots of money in the long run.
A car with a hood in good condition is advantageous
Doors in good condition with minimal dents etc
A good quality and well maintained interior can save you doing a retrim!
Buying a car in the colour you wish to have your bertini can save a lot in the paint shop! Or at least a similar colour can help cut the cost.
There is a temptation to by a crash damaged or write off car. However the resale value of the unused Z3 parts is high so this rarely makes economic sense.
A nice set of 18 or 17" alloys in good condition of an expensive audio system can save money if you wish to retain them in your Bertini.
Last edited:


Global Moderator
M Power
Dec 2, 2011
Model of Z
Most Z3Ms are the older shape cars and very few later facelift Z3Ms were made.
they have the s50 engine with 321 bhp
Z3M's weren't "face-lifted"

There were three engine versions depending in where you are in the world. Europe started off with the S50, and then changed to the S54. North America had the S52 (250ish BHP for a while and then changed to the S54.

badman gee

The s50 did get minor changes. Early ones had no aircon (as standard),no roof lining, non chrome headlights and no headlight washer jets.

hard top

Zorg Expert (I)
Dutch Zeds
The M44 Massive
Dec 5, 2011
BMW Z3 (1996-2001) Model History
  • 1995 : The Z3 appeared in the Nieman Marcus Christmas catalogue.These cars were all Atlanta Blue with beige upholstery
  • 1996 : The first demonstrators arrived at the dealers in March of 1996.
  • 01/01/1997: Z3 1.9 rear-drive Roadster (140 bhp), 5-speed gearbox or 4-speed automatic,ABS,PAS,alloy wheels, central locking, electrical windows and mirrors, electrical seat adjustment,airbag. Options include air-conditioning , ASC+T traction control, leather trim & electrical hood
  • 01/08/1997 : Z3 2.8 (193 bhp) launched. Equipment as 1.9 plus ASC+T traction control, limited slip differential, electrical hood, leather upholstery, larger 16-inch Z-Star alloy wheels, trip computer
  • 01/09/1997 : 1.9 now has ASC+T traction control system.
  • 01/01/1998 : Smaller M-style leather-trimmed 3-spoke steering wheel. Option ; Aluminium hard top with heated screen
  • 01/05/1998 : M Roadster 3.2 spec as Z3 2.8 plus four exhaust pipes, air-conditioning, 2 airbags, heated electrical mirrors.
  • 01/09/1998 : M Coupe launched, specification as M Roadster.
  • 01/04/1999 : Special edition 'Orinoco' and 'Fiji' 1.9 and 2.8 launched.
  • 01/07/1999 : Z3 1.8 and 2.0 launched. Restyled rear end, chrome-rim headlamps, chrome-rim instruments.
  • 01/02/2000 : 2.0 Cosmos, Velvet, Aegean and Mora editions (all £26900).
  • 01/09/2000 : Z3 2.2 (170 bhp) and 3.0 (231 bhp) launched.
  • 01/02/2001 : Z3 2.2 Sport and 3.0 Sport launched. 2.2 Sapphire and Titanium editions (both £25950 new)
  • 01/03/2001 : Revised M Roadster and Coupe with 325 bhp engine, DSC III stability control system, uprated brakes.
  • 02/12/2001 : The 250,000th Z3 roadster > Jet Black with a red top and Mugello red seats with black inserts. The console is trimmed with red birchwood and the roll bars are black leather in front and red leather in back held together with red stitching
  • 2002 : An in-dash CD player was newly standard for 2002.
  • 06/28/2002 : Production of the last Z3 roadster.
  • 2003 : BMW's Z4 replaced the Z3