CRX ls intake question?

Is it possible to put a intake manifold from a 88 integra ls on a 89 CRX?

No.
LS has a b-series, CRX is a d-series engine.

That means a b series engine? Cause the LS caries a D16A3 and his CRX is a D16A1 I believe... I know the CRX has 108 hp and I am pretty sure its a D16 of some sort

Oh whoops.. sorry man. I'm not sure how much of a gain you'll get if it does fit though. Check the inlet diameter of both and see if the Integra one is bigger.