by Ember » Wed Jan 28, 2015 3:45 pm
The colour that makes the biggest change depending on the primer beneath is yellow. Never spray yellow over black or grey primer, it will take a million coats (give or take) to get rid of the green-ness. Always spray yellow over red or white primer.
White should also be sprayed over white primer.
Red is one that you can have fun with. Sprayed over a black base it'll give you a very deep, rich colour. Grey will give a slight darkening to the colour. White can make reds lighter, but it can also make them look pinkish or quite orange. If you want intense, vibrant red it's best to spray over a red primer.
Most other colours are best sprayed over grey.
But it can be fun experimenting with colour coats over various primer bases. British Racing Green I'd spray over a black primer. Lotus green I'd spray over grey or white.