How Long Can the Car Sit on Ramps?

[tjs121]

I'm planning on replacing a number of items that either need replacement ASAP or I have no idea if they've been addressed in the past:
-oil filter housing gasket
-cam cover gasket
-DISA
-VANOS oil line
-CCV
-water pump and aluminum pulley
-pulleys
-both drive belts
-expansion tank
-radiator thermostat
-radiator hoses
-coils and spark plugs

I've never done any of this stuff on a Z4 before so none of it is too crazy but there's always fun issues that like to show up along the way. I know I can't get this done in a day or probably even a weekend so the car would be sitting on some wood ramps I made without moving for multiple weekends and depending on how cold it is, possibly 1-2 months before it's drivable again. Is there an issue with this since most of the weight will be on the rear tires (which are brand new) for however long it takes?

Side note: does anyone know the part numbers for all of the deflector/idler pulleys for a 2005 3.0 M54? I checked realoem and can't figure out exactly which ones I need.

 

[brillomaster]

most project cars sit on stands for years lol, so no problems there.

as for the rear tyres they might flat spot if left in the same place for months on end, so i'd either get some wheel cradles, or just put the rear of the car on stands too. Jackstands are less than a tenner each.