Hello. Which rods are the lightest for 4G63 that will handle 650whp? Any suggestions will be appreciated. Thank you.

 

Eagle H beam rods can handled 650 and are reasonably light (654 on my car's Eagle rods for the last 60k plus miles)
For piece of mind I'd go with the R&R 'I' beams, which are about the same weight as the Eagles only stronger.

John-

 

GRP Aluminum Rods are light and can handle the power

 

For a steel rod, the Eagle H beams are underrated and will do it, especially if the torque is low