I have a article directory which has more than 16000 pages, there are many spam authors who post more than 250 articles everyday, because of the load it generates my hosting provider told me that it took more than 10% of memory allocation, i have decided to remove the articles, because i was not earning from those pages. Now i have blocked it in robots.txt and went inside google sitemaps and removed the URL. Now my traffic for my subdomains in that same site is growing every day, those are quality traffic, my question is because i block and remove all the 16000 pages from Google will it affect my subdomain traffic and rankings? But to be frank with you i have done, there is a slight dip in the traffic. But may be weekends may also be a reason for it.
Unfortunately this is true, if you run a spammy website on your main domain all your subdomains will suffer, i don't know if it is true and if one of your sub domain get's banned, will then and the main domain and all his domains will get banned to?
If the main site does not get banned, if i have to stop all the cached pages in the Main site from Google will that affect sub domains traffic.