With 317 heads and a lq4 short block the cr should be around 9.4:1. If you plan on a turbo down the road I don't think it would be worth the trouble to change those heads, then probably want another stock set later. Also it might be hard to get rid of a set of heads that are modified like that if or when you do want another set. I have 317 heads on my truck with 9.2:1, and a tiny 212/218 .59/.60@115 cam, and before the turbo it made 33xwhp/35xwtq through an 80e and transfer case. I suffered through for 1 1/2 years, but now with boost it made 627whp/653wtq so it was worth it to me.