chevyaveo413
"You don't want 11:1 if you have a turbo. Read the tech article on my site regarding effective compression ratio. 91 octane gas can safely go up to about 11:1 compression with a fairly conservative tune. With 9:1 compression you'll get better off boost performance and be able to run about 13psi safely. 8:1 compression you can run about 20psi but then your turbo is working a little too hard. My Impreza had 9:1 and I ran 13 psi which didn't give me a lot of top end, but I had a nice flat torque curve which allowed me to keep up with much more powerful cars. In fact, one STI was putting over 400 to the ground and he was only a little faster on a long straight. I had more useable power through all the corners.
If you are serious about this, start with a used block (http://www.car-part.com). Once you get it, take the pistons out and send them to JE pistons. Ask for 8.5 or 9:1 compression pistons and rings. With just the lower compression pistons and boost, you should be able to get almost 200hp out of the 1.6 and still have a 100,000 mile engine if you tune conservatively.
Read the emanage tuning article on my site as well. You will find it in my Subaru section.
Could you also repost this for others to see, I think it might be helpful.
Chad "


subachad
The article is called compression vs boost.

http://uniquemotorsports.com/tech_artic ... ticles.htm