Does the manifold look like this
http://www.nissanpatrol.com.au/forum...2013/02/74.jpgsorry for the crap quality its an old pic.
Anyway these crack, the T3/4 turbo if its a T3 hi flowed to T4 thats fine coz its oil and water cooled, if its only oil cooled then its like a Ebay special and i've cracked 1.
Rb30 motors are tuff as, i drove a vl with a cracked head for 2 years lol and when i don the head i lowered the comp and slapped a turbo setup on it and it loved it it.
The car at 4.5k sounds cheap but it depends whats done to it, if its all stock apart from the setup then i would say that high coz i could get a bog stock 1 clean as for 3g's just depends what its got yeh.