Spring ratings
 

I am wanting to get a set of lowering springs. They have ratings and they are from like 450-600 ft/lbs front and 200-300 ft/lbs rear. I understand why the front is higher and what ft/lbs mean but why does the rating cover a large gap? I have a v6 now but will convert to a 351w. What is a good rating to get. I plan to make it a fast car that can handle. Not just in strait line. Also I like the Eibrach. Are they any good? What is the best? Will I need new cambers? Thanks for your help.

well...
 

There are 2 types of springs. Progressive and Linear. Just for reference, the stock springs are progressive. Anyway, progressive springs are rate with the numbers you mentioned. For example.. 450-625. That means that as the spring compresses it gets harder to compress. So when it is at normal height it would take 450lbs to compress the spring 1 inch. As it is compressed more it will get harder to compress. So then it will take 625lbs to compress the same spring 1 inch. Follow? :) Progressive springs are better for street driving because they offer a softer ride but respond well when you hit the corners. Linear springs are rated with a single number. Perhaps 650. Meaning it would take 650lbs to compress the spring 1 inch throughout it's entire travel range. Linear springs are better for racing applications because they are a good bit rougher but offer much better handling, cutting down on body roll significantly. Hope this helps.

Bob