[bobcowan]

You have a few choices, but not many. On the street I have some oval K&N filters in billit alum housings. But they were custom made by the company that made my throttle bodies, and they're no longer around.

On the track I use open trumpets. I overhaul the engine at least every two years. There is no measurable wear in the cylinder bores or crank journals.

Pierce Manifolds hase some nice screen filters that don't restrict air flow.

Traditionally, people used a "Tea Strainer" filter on top of a trumpet. But, those cost me 100hp, proven on the dyno.

Must stack EFI throttle bodies are made to fit filters and trumpets for Weber carbs. So find a Weber filter that fits your needs.