i have "site A" hosted on "server A" a friend has "site B" and "site C" hosted on "server B". if i link to site B and he links me from site C to site A, will it pass link juice to me? all sites are from the same topic. also if someone knows an article / blogpost where i can get information about good link exchanges it would be great.
It should be fine. I believe the only time an issue would come up is if site A on server A would link to site B on server A in which case no juice would be added. Youre case should be fine
I have a bit doubt about its success though i am not sure about it so i am not against it but now a days google is very watchful about this type of linking and if it may consider as spam then it may not be as effective as you like to but if it is OK for google then i think it be very helpful to you.