header?
 

does an ej20 header have the same flow as an ej25 header...i know when your buying parts there bolt patterns and size are the same also the bends but i want to kno if the flow is the same:surprise:


thanks guys

Stock to stock, they are identical.

Aftermarket, the EJ25 headers have better options due to the oil pan shape.

Generally the EJ25 equal length > EJ20 equal length just due to how long you need to make the tubes to clear the oil pan. EJ25 you can "cut the corner" of the oil pan and get some length off the longest runner so all the equal runners are longer on the EJ20 designs.

unequal length... probably very little difference.