The original motor is gone, it blew a rod threw block. The 280z motor is know as what engine designation? Would this be L86. Also the 280z motor in the 240z has the twin carbs, not fuel injection. How hard is it to dial these carbs in. This is the reason the car runs rough.Are there any headers that would fit the 280z motor in the 240z car. Supposidly the car carves corners really well because of the chassy reinforcements and having been lowered.