Where's the 340 crate engines???

Just something to chew on, and this is from experience.

My 340 pulled really really strong on the top end, I used 5.13 gears and shifted at 8000.

The same exact motor but without the good Ross pistons and Eagle H beam rods in a 360 leaves harder but doesn't run as strong on the top end. I use a 4.89 gear and shift it at 7500.

They both ran the same ET within .01 of each other.

Having said that I'll tell you this, anything over 8000 RPM's shook the valve lash adjuster lock nuts loose. The valvetrain geometry is bad (we all know this) on the 59* blocks so trying to continually rev one much higher than 8000 will get you a bunch of pieces parts.