Heavyside Lorentz units and Gaussian units

What is the relation between Heavyside Lorentz units and Gaussian units?

From this Wikipedia article, I noticed there are $4\pi$ difference between them, but my TA wants more.

Is there other relation or important property for each unit system?

• What kind of TA tortures their students with units? – Jonas Greitemann Sep 17 '14 at 16:15
• Anyway, Wikipedia seems to confirm that Heaviside-Lorentz is halfway between Gaussian and SI. As a rule of thumb: put the $4\pi$ where you'd put them in SI units but replace the $\varepsilon$ and $\mu$ by $c$ just as in Gaussian units. – Jonas Greitemann Sep 17 '14 at 16:18