The ratio between 630nm and 660nm....
First I would look at the specs of each of those LEDs, what is their entire range and what is their output at the recommended voltage and current?
For example, different 660nm's will have different ranges and outputs, some may be 655-660nm, 660-665nm, 650-660nm, 655-665nm, 640-660nm, 655-670nm, etc.... But they are all advertised as "660nm". Those narrower ones if used in excess, can and probably will cause stunted growth and bleaching. 630nm, and every other color are like that too, and for the most part, all blue LEDs are very narrow and only cover 2-5nm per each, so if too much blue is used, not only will you stunt your plants, they will probably bleach too. A lot of people are not aware of the differences between one LED to the next, and try too hard to get enough targeted light to the bottoms of 3-4 foot tall plants by using extra 660nm, and narrower lenses, while they are getting better 660nm coverage at the bottoms of the plants, they are hurting the tops of their plants.
In my experience, it is best to try to spread the color out as much as possible, and cover as much colors as you can without adding too much of any 1 concentrated color. On the red side, you'll want to cover as much from 600-670nm as you can, favoring the 670nm side a little heavier, then also 5-10% of the total LEDs should go to farred 720-750nm.
The most important spectrum that is left out in a lot of LED grow lights, is the 500-600nm area. 65% of the color I use is from 620-670nm and 720-740nm, 10% to 400-500nm, and 25% to 500-620nm.
White LEDs are a great thing, you could easily omit all the blues and greens if you use them, and swap them for a cool white LED.
Here is a typical color spread of a cool white LED:
To achieve 10% blue in your overall LED mix, simply use 1:2 ratio, 1 cool white per 2 red/farred.
Good luck with your next LED light