Below is the meaning of the entries:
Crypto Engine Connection Map:
> size = 8, free = 8, used = 0, active = 0
>
> -- The map size of the crypto engine. The map size
> will exponentially double if the number of
> IPSec tunnels outgrows the map size. Note that
> each IPSec tunnels consume two crypto connections,
> one for outbound and one for inbound.
>
> -- The number of free connection entries in the map.
>
> -- The number of allocated connection entries in the map.
>
> -- The number of connection entries that is able to
> cryptographically protect IPSec traffic.
You see 4 entries for the 2 tunnel since you get 2 unidirectional IPSec SA for every tunnel.
This doesn't give you the max tunnels allowed. Also, remember one vpn tunnel is 1 IKE SA plus 2 IPSec SA (that is if you have only one acl on your crypto acl - the more acl the more SA).