145 2.0 - Any Ideas What Amps Battery To Use???

Hello again guys!

Another minor problem with my 2.0 Cloverleaf!!

Have changed my alternator and thought that would solve the problem.. Then changed the battery with one out of a 3 series bmw when it wouldnt hold its charge...
Every time i start the car its really slow and sounds like the battery is going to die but then starts up at the last minute.. (I dont think this other battery is knackered tho)

Any ideas what size in Amps battery to use?? Iv seen a few different batteries on ebay and all have different Amp outputs i.e. 360Amps, 440Amps and 640Amps....

Which is suitable for my car?! Obv the less amps the less power you have but if I have a high Amps battery will it not eventually fry the starter motor?!

Open to suggestions!!

The amps on the battery is how many amps it is capable of delivering, not how many amps it will deliver; that is determined by teh resistance of the starter motor, so don't worry.

Have you checked all the earths / contacts?

Ahh! Well problem sorted now, there was something draining the battery - still dont know what it was. Pulled a fuse next to the relays at the front of the battery conpartment and its stopped the drain (the fuse was 7.5A and the one closest to the battery housing)

Any ideas what this fuse controls? The car runs fine and all the electrics work fine too...