I finally found the best engine to put in an old datto that has all of todays technology but from 1975.
Its all alloy, cosworth twin cam 16 valve and 225 pounds and can be run with no pollution gear!!!
The ugly chevy vega can donate all of its guts to our beloved dattos anyday!
http://cgi.ebay.com/ebaymotors/1976-cosworth-vega-5-spd-perfect-int-fresh-valve-job_W0QQitemZ4609348725QQcategoryZ39405QQrdZ1QQcmdZViewItem

Lucky people in the US can make some serious monsters.
DDgonzal pity you arent in California to take advantage of this running gear.
A cosworth engine with a cast iron block in Australia is available no cheaper than 10k$au and you guys in the states can get the full alloy version for 650 bucks with gearbox and lsd differential!!!
http://h-body.org/library/vegabob/vega-history-complete.html