ok, is the block from a 1992 g20 the same as a 1990 240sx?

Absolutly NOT!

ok..so they cant be swapped?

Nope.

Originally posted by 1992G20
ok..so they cant be swapped?

Anything can be done with enough money.

But it won't be an easy swap. It'll also make a sow's ear out of a silk purse.

A Nissan 240SX is powered by a KA24(D)E while the G20 is powered by an SR20DE. The KA24DE is larger (not only in displacement, but in actual physical dimensions). While you can put an SR20DE in a 240SX, you cannot put a KA24(D)E in a G20.

KA24(D)E: Work horse, from trucks to sports cars, better suited to a truck though.

SR20DE: High revving power plant, suited to just about any car where a 4 cyl would be used.