The windage tray is mounted on the standoff studs using serrated lock nuts--these were included with the studs. The tray itself is Moroso PN 23030. The louvers allow oil thrown off the crank to drain into the sump, and the tray cuts down on airflow that can whip the oil up and into the rotating assembly. It's also Teflon coated to further aid drainage.
The idea, according to Moroso's Brint McLellan, is locate the windage tray as far away from the rotating assembly as possible. If the tray is too close, oil thrown off the crank may not have enough opportunity to drain through to the sump and can get whipped back up into the crank. Note the cut-off studs; this is as low as we could get within the confines of our street/ strip pan. Moroso warns that "some trimming" may be required when installing a windage tray; we had to clearance the dipstick area.
The minimum clearance between the rods and the windage tray, according to JMS racing, is 1/8 inch; with the tray at its lowest possible position, we had 1/4 inch.
Our Summit Moroso oil pan kit came with a assembled high-volume pump/ pick-up combo. To facilitate our on-the-dyno oil pan swap, we ordered a comparable high-volume pump from Federal Mogul, along with new oil pan gaskets. The matching pick-up for our new pan was a convenient bolt-on design.
After removing the windage tray from our big-block mule and reinstalling the standard ARP main studs, we lifted our new tray into place...and couldn't quite bolt it on. Moroso designed the main cap partitions on this pan to work with the main caps and bolts on Dart and Merlin big-blocks. When using a factory block with studs, clearancing is necessary--and normal.