What the hey, here's the rest of the comparison pics.

I just happen to have a complete D15 and a 2.0L 4g63 turbo head in my shed. The DSM head pictured is from a 95. The '95 heads have smaller intake ports and larger exhaust ports on the than previous years. Head ports on the 1g DSMs are really too big for their own good. The '95+ 4g63 engines are a bit higher compression (8.5:1). They still make the same amount of power as the 90-94's (7.8:1) despite the compression bump because of a smaller turbo.

I'm only posting these to point out that one engine was designed for a turbo, and one was not. It's visually apparent. That doesn't mean that a turbo won't help the one that's not built for it, but it helps you understand what limitations it may face with moving air in and out of your engine. That's what you have to do to move enough air-to burn enough fuel-to make a lot of power. Honda engines are fuel efficient because they're very restricted by design. A junkyard setup is not going to help you much with that.

It would be best to eventually replace your intake and exhaust stuff with parts that flow better.



Here are the intake sides of the heads...