When training 100 Eva/Spirtus, you get:

              Eva    **Spirtus
Faustus     33.33        30.30
Respia      37.50        21.00
Sespus      27.50        24.50
Higgrus     25.00        10.00
Awaria      *6.67         0.00
Horus       *6.50         0.00
Rodnus       0.00        50.00

Total       136.5       135.80

*  Unconfirmed
** All Spirtus numbers unconfirmed

For every 100 Spirtus you train, any healer will heal you as if having
an extra 80 Faustus, e.g. a newbie healer with no Faustus, will heal as 
fast as an 80 Faustus healer.

However, this extra speed does not come cheap, though it's still better 
than training Faustus directly:

Even though you may heal a lot faster, your spirit reserves will not 
drain any faster than usual.

The negative effect is that your health will drain as if you had trained 
the extra Faustus directly. For lower level healers this can make a huge 
difference.
As an example, a newbie fen healer healing someone with 300 Spirtus will 
suffer complete health drain in only 9 seconds (25 seconds if the healee 
has only 100 Spirtus).