This Mazda RX-8 from Iceland is powered by a 5.7 L LS1 V8 from a 2004 GTO. The project began after the RX-8 had a blown engine and took about 3 weeks in the owner’s spare time. The engine mounts are custom and they could only use the header from the right side of a Camaro while the left side needed to be custom built. The car also uses a stock 4.44 differential and a Camaro steering rack and oil pan. Overall the car weights 3240 pounds with 53.2% bias in front. The owner is still trying to figure out how to get the gauge cluster to function. I know there is some interest in a kit for this type of swap so lets hope someone builds one.
Update: This project completed and added videos of it below.
Update 2: The owner was kind enough to expand more on this build in the comments below. I have updated the article to reflect his comments.
Update 3: Hinson Super Cars is developing a RX-8 LSx swap kit.