Iv got a really load whine which sounds like its the alternator the car is a 1.6 8v 1998 every now and then i get the battery light flickering on and off would it be worth changing the battery first to see if its something to do with that or just get another alternator and if so what amp should i go for is it the higher the better? also if i fitted a throttle body from a 1.8 or something make much difference?