So I just got my lq4 swapped 240sx running. I was planning on just driving it as is for a while with stock internals. But, I got a cam from Texas Speed cause of their sale. I knew I had a misfire so I was diagnosing that before taking it apart. I believe the issue is the lifters cause I have great cranking compression (all over 180)but running compression seems low to me (60-70 on the driver side and 90-100 on passenger side). So it looks like I have to pull the heads off the car. My question is, should I go ahead and get a double roller timing chain and high volume oil pump while I have it apart? Or do you think the stock components will be fine? I have new push rods, valve spring, and the trunion upgrade kit already. Is there anything else that I'm not thinking about?

 

Might as well do the timing chain and oil pump. JP makes a nice one, however double rollers are really overkill. Also you might as well replace the lifter trays too if you aren't using a linkbar style lifter. You need timing cover, water pump, and head gaskets and the oil pump o ring if you do the pump.

 

Most people change out springs and pushrods and i would go ahead and change out the pump.. maybe try and ls2 timing chain? not too expensive