[JLerum]

I also think that the more compression that is run, the better the big ports function with the stock GM L-72, L-78, LS-6 cam. I think Pete's L-72 motor is a good example of why more compression is required. The lifters needed more lash to shorten the duration of the cam to fit the compression. I figure that the right dynamic compression should be 11.8 to 1. When you think of it, Pete's motor was running a lift of .480's after the lash was set to get the proper dynamic compression. Their are some good book out there that explain this very well. Pete I'm not picking on you as you have some great really quick rides, it's just that everyone is probably familiar with the really good article on your COPO dyno L-72 in MCR. Look forward to the ZL-1 dyno session. Which soon to be published issue will it be in?

Jim Lerum LS-6

PS: The 291 cast heads have 327cc ports which also hurt the low end port velocity for building torque. This right where we need to operate with the manifolds.