Empi 3447 Heat Riser Block Off Plates. Compatible With Exhaust Manifold Preheat Pipe Outlets
Empi 3447 Raw Steel Block Off Plates For Vw Exhaust Manifold Preheat Pipe Outlets. Many Air-cooled Volkswagen Exhaust Systems Have Preheat Pipes That Run From The Exhaust Manifold By The Cylinder Head Flange Up To The Intake Manifold. The Main Function Of These Preheat Pipes Were To Allow Exhaust Heat To Travel Through The Preheat Pipes Warming The Intake Manifold. This Prevented The Intake Manifold From Icing Up While Aiding The Automization Of The Fuel Traveling Through The Intake Manifold. With A Variety Of Different Carburetors And Intake Manifold Systems Many Of Them Do Not Offer Preheat Pipe Hook Ups. Heat Riser Block Offs Would Allow You To Block Off Exhaust Preheat Outlets. Sold As Pair