Tundra and Sun-Synchronous Orbits

[Kerbalsaurus]

How do you do these orbits in the stock KSP system, specifically on Kerbin. I know how to do equatorial, polar, and geosynchronous, but that’s about it. What are the parameters for these orbits?

[Gargamel]

For tundra, do you mean Molniya/Kolniya orbits?     Those are just very high Ap, low Pe, high eccentricity inclination orbits.    To make a relay cloud from that, just space out 3 satellites like you would in any other orbit.   
 

Edit:   Meant inclination, already described the high eccentricity with the Ap/Pe

Edited August 20 by Gargamel
Whoops. Meant inclination, said eccentricity

[Raptor42]

You cannot achieve Tundra nor Sun-Synchronous orbit in stock KSP. This is caused by the way orbital mechanics is simulated in the game.

In real life, orbits of satellites are affected by pertrubations caused by the oblateness of the Earth. This causes the satellites to drift from their original orbit over time.

In sun-synchronous orbits this effect of Earth's uneven gravitational field is used to shift the orbit just the right amount such that the satellite passes over the terrain at the same time of a day every time it passes over it (for example each it's always noon/midnight in the area over which the satellite passes).

Since the planets in KSP all have uniform gravity these pertrubations do not appear (the orbits are stable and are not being shifted) and therefore the orbits you mention are impossible to achieve.