Danger using a smaller pulley with out suporting mod's can destroy the eng. A number of people have gone to a 3.4" pulley with just opning the Airbox and removing the u-bend/resonator but a few have had problems with even this small change of pulley. The best thing to do is get a scanner of some type IE: Autotap or DHP programer and scan for knock retard some eng have knock retard with the stock pulley
anything smaller is asking for trouble with out knowing what the eng is doing. IE: 3" pulley = headers/ported ehxust and cam or rockers. good luck
