D15Y7 upgrades?????

Ok i have a 92 CX with a 16 valve 1.5 d15y7...iv already put on headers, a cheap cold air intake, and cut the cat out of it but i'm in serious need of some more power.
i want to keep it N/A if at all possible!! i know a lot of you are gonna scream at me to boost it, but i 1) don't have the money and 2) am going to college so i don't have the time... so with that out of the way, whats a good way to give me a few more hp???
also i have a 06 cobalt SS motor (for those that don't know its a supercharged 2.0 liter motor out of a Chevy) has anyone heard of swapping one into an eg???
i want to keep it N/A if at all possible!! i know a lot of you are gonna scream at me to boost it, but i 1) don't have the money and 2) am going to college so i don't have the time... so with that out of the way, whats a good way to give me a few more hp???
also i have a 06 cobalt SS motor (for those that don't know its a supercharged 2.0 liter motor out of a Chevy) has anyone heard of swapping one into an eg???