I am replacing the distributor in a car of mine, its an HEI and I noticed that the springs under the rotor are much tighter in the new one as opposed to the old. I assume this just brings the full advance in quicker. As this is not a stock engine i am wondering what i should do to decide what tension of springs to use. What is a good way to determine this. Thanks. Chris =) I think the exhaust fumes have finally gotten to me!!