For the guys that like to play with numbers.

From Bullet's Lobe List:
Adv. .050 .200 Lobe Lash Lobe Type
Intake : R320/564 320 289 213 0.5640 0.0093 CRS
Exhaust : R340/563 340 304 224 0.5630 0.0140 CRA

Lobe Type explanation:

• The first letter is either "C" for a conventional shaped nose on the lobe, or "D" for a dwell nose. Dwell lobes are often used when there is a lift rule, such as NHRA stock classes. Dwell lobes are usually not well suited for higher RPM applications.
• The second letter is either "R" (RPM) for lobes suited for higher RPM applications or motors with numerically high rocker ratios, or "T" (Torque)for lobes suited for lower RPM or motors with numerically low rocker ratios.
• The third letter is either "S" for symmetrical lobes (opening and closing ramps the same), or "A" for asymmetrical lobes (opening and closing ramps different). Asymmetrical lobes usually have a slower closing rate to help prevent valve bounce.

Valve lash numbers are given at the lobe and have to be multiplied by the rocker ratio to give the valve lash at the valve. Lobe lash numbers of less than .012" are considered "tight lash" and tend to be more aggressive lobes.

(I don't think the lash to rocker ratio equation applies with this one!)