I was exaggerating with that comment. The force required to compress a spring 450 lb/in an inch is 450 lbs. A damper that has a resistance of 450lbs. at 1 in/sec velocity will not allow the 450 lb/in spring to be compressed at all with that amount of force, thus my steel rod damper comment.
Recommended damping rate for a spring rate will depend on the application and your target bounce frequency on your setup or how much you are willing to compromise. The higher the bounce frequency the harsher the ride. The lower the frequency, more compliant it will be. This is a very VERY simplified description I just made of just one single factor to choosing a damper for a spring. There are many more factors to consider.
I'm not going to pretend I understand this fully, as I myself am in the process of learning this stuff and have been for a while. There a many other members on this board that better qualify to answer your question. And by the lack of response you're getting, this should give you an idea of complicated this subject is. So much so that nobody, besides myself, has been willing to comment thus far.
I will share a couple of links to some literature to try to help you. For the sake of not wanting to give bad or wrong advice and steer you the wrong direction, this is as much as I'm willing to say. I'd love to see what some of our more established suspension nerds have to say about this subject as well. I have my own thoughts about this, but I'd rather keep to myself until have confirmed my own 'theories' and math to be applicable.
This one from a suspension nerd on a different board.
This one is not auto specific, but much of it can be applied to auto apps. Dampers, at th end of the day, are dampers regardless of what you are using it on moto, quad, snowmobile, mountain bike etc.
Hope this is more help than it is confusing. Cheers!
