Uprating engine on 1986 Honda Civic 1.5?
 

I have a 1986 Honda Civic Shuttle estate with a 1.5 engine and autobox. Great little car but sometimes lacking in power, especially on a long incline while carrying a load.So I'm thinking of either some way to upgrade the existing engine, or drop in a more powerful engine from another model.(My pipedream is to install a 3.2 V6 from a Honda Legend but would value more sensible suggestions!)Note: I don't want to replace the car with a different one, just modify this one.