Tires what type of tire use the bmw z3 originally

Depending on the manufacturer and type of tire, the tire pressure spec's will be different, The labeling imprinted on the sidewall of the tire will specify the recommended tire pressure. Most average tire pressures used for highway tires is 32 P.S.I.

General advice:
Oil/filter replace.
Air filter replace.
Fuel filter replace.
Brakes/pads/oil/discs/dust proof sealers,
Timing /tension.
Valves adjust.
Wheels alignement/balance .
Tires condition/pressure.
Engine compartiment belts.
Battery/alternator condition/charge rate.
Lights alignement/hight ceck.
Thermostat open/thermoswitch triggers fan.
Coolant ceck/change.
AC pressure.
Doors/trunk/hood/roof look/hinges oiling.
Remote battery ceck.
Pretty much everything if u care 4ur car.
Cheers.

When was last "healthy tune up". Plugs,all filters including FUEL filter? I would start there to give you a good "ground zero" starting point. I suspect "tired" plugs, but do the full tune up.

How did you find out about the speed difference? Have you changed the wheel and/or tire size with something aftermarket?

if wearing on teh inside then then they are towing out ,unless they are laying over at teh top too much either way its a visit to the chassis align workshop as it would seem your vehicle has been in a bump or a shunt somewhere along the line

As with Most Vehicles this is an Indication of 1 or more tires needing attended to. Generally speaking it is warning of a Low Tire Pressure.
Check (or have Checked) all the Tires for the specified Tire pressure and inflate to "Recommended" PSI as found on the Tires, (raised type lettering on Tire) closest to Rim/ Wheel.

If it is Low Pressure, with Economics as they are, have tires inflated to Maximum load can increase gas mileage

Hi. The original equipment tire size is 235/55r17, with a 17x8 wheel size. Up one tire size in a 17 inch is 255/50r17, with nearly the same circumference, but much wider and more sidewall profile. Up one (referred to as "plus one") wheel size, 18x9 inch, would be a 235/50r18. Down one tire size is 215/60r17 with narrower tread width and much more sidewall height. With B-mer's engineering you have quite a bit of leeway with larger tires and wheels, more than most manufacturers. There is lots of software on wheel seller sites that will let you see different tire wheel combinations on your vehicle. Check them out. Hope this helped!

Usually caused by unusually wide tyres/wheels. This is called in the UK 'tramlining' and is nothing to worry about though can be disconcerting. Owing to the increased width of Z3 spec. tyres over standard tyres there is more of a tendency to follow abrupt changes in the road surface. Keep those hands at 'Ten to Two' on the steering wheel.

Uncle Lodger.

yes they will you just may need to use a wheel spacer

I have a replacement roof for my 1997 BMW Z3, could anyone give me advice how easy or hard its and could one man do it on his own?