Almost 2600 fpm.
The cruise photo makes for an interesting comparison. Photo on right is my -8, last fall. Same altitude, pretty much the same TAS, a little less fuel burn for the 390. Need more MP and RPM to match the 540, no surprise. In the context of this thread, note the angle valve doesn't need or want much advance (here 23 fixed) cruising at peak EGT. The Surefly allows a full range of fixed or variable timing, so it will work fine on either parallel or angle valve.