one machine has crashed, and i have only .tgz backup (all files from dir: /var/lib/pgsql/8.4/data/base/70503486/*.*)
how to restore this data on new machine with postgres 8.4
You should better ask that on pgsql-admin or pgsql-general.
Anyway, if you only have files from /var/lib/pgsql/8.4/data/base/70503486 directory, there's nothing you can do with only these files. Hope you have a dump of this database.