dont know of a website, but it matters for each engine you have and what variations it has in it.
I have a mopar repair book that has all the stock timings in it,
all you have to do to make sure your timings are correct is make sure the vaccuum advance hose is off the carb, and plugged, and make sure the engine is heated to running temperatures. ... you need a timing light usually
On my Big Block 440 in my 1973 dodge charger, the timing plate was put on way off so i had to do it by ear, i have it tuned perfectly its not very hard.
have fun.