Improve 4 Cylinder Engine Q: Is there anything I can do to improve my 4 cylinder engine? A: Yes, especially the Iron Duke 2.5L which came in the first 3rd gen cars: Holley T.B.I. unit (20% larger unit) Edelbrock Performer T.B.I. manifold Hooker Super Competition Headers Holley open element air cleaner K&N filter air cleaner NOS nitrous kit (single fogger, 40 or 70 HP) Turbo Muffler B&M shift improver kit for 200C tranny
