SQL Server Query: Fast with Literal but Slow with Variable

Probably it is because in the parameter case, the optimizer cannot know that the value is not null, so it needs to create a plan that returns correct results even when it is. If you have SQL Server 2008 SP1 you can try adding OPTION(RECOMPILE) to the query.

You could add an OPTIMIZE FOR hint to your query, e.g.

DECLARE @id INT = 1
SELECT * FROM View1 WHERE ID = @id OPTION (OPTIMIZE FOR (@ID = 1))