Here's some decent reading on the subject of engines:
I4
Specs - http://archives.media.gm.com/us/powertrain/en/product_services/2010/gmna/Spec%20Sheet/Ecotec/10_LAF_n.xls
Story - http://archives.media.gm.com/us/powertrain/en/product_services/2010/gmna/Stories/Ecotec/10_LAF_n.doc
V6
Specs - http://archives.media.gm.com/us/powertrain/en/product_services/2010/gmna/Spec%20Sheet/HFV6/10_LF1_n.xls
Story - http://archives.media.gm.com/us/powertrain/en/product_services/2010/gmna/Stories/HFV6/10_LF1_n.doc
I4
Specs - http://archives.media.gm.com/us/powertrain/en/product_services/2010/gmna/Spec%20Sheet/Ecotec/10_LAF_n.xls
Story - http://archives.media.gm.com/us/powertrain/en/product_services/2010/gmna/Stories/Ecotec/10_LAF_n.doc
V6
Specs - http://archives.media.gm.com/us/powertrain/en/product_services/2010/gmna/Spec%20Sheet/HFV6/10_LF1_n.xls
Story - http://archives.media.gm.com/us/powertrain/en/product_services/2010/gmna/Stories/HFV6/10_LF1_n.doc