What is the process to hollowing the cams like our OEM ones? Are they casted hollow? Or are they casted solid, and then drilled? I'm just curious as to why no aftermarket cams are hollowed out.

 

bump

 

to reduse rotating weight, same reason why flywheels are lightened. I dont know if they are drilled or cast. I would imagine cast since they are mass produced. I think the reason aftermarket ones aren't hollow is cause they need to be durable and hollowing isn't worth much anyways.

 

Anyone have some stock cams laying around that can look down the inside to see whether inside surface finish is cast or drilled?

 

It's my understanding they are cast hollow.

 

Okay, judging by the picture, they are definitely cast hollow. There's no way to drill out the center like that.

On which EVO did Mitsu start hollowing out the cams?

 

The 7, I believe