My friend has a 94 g20, which has the low port intake manifold... he blew the motor like acouple weeks ago, so i told him i had a motor for sale... but the thing is my motor is out of a 91g which is the high port manifold... so my question is can the highport motor be swaped into the 94 g20??? or would it be possable to swap the motor and reuse his lowport manifold???

As far as I know... The intake manifold is the only real difference between the two motors... Aside from the fact that the cams from the 91' motors are better as well... So swapping manifolds has a fat chance to work... :) Kinda' like when you buy a JDM motor... they always recommend for people to use their stock USDM manifolds over the JDM block in order to keep all the emissions crap on there....