thanks robot and i just checked my old ones and they were at 0.045. The guy that just installed the engine in this other car had some of the gaps at0.050-0.055 may why it wasn't running right. I went and got some of those accel header plugs because they are shorter and the delcos were making the boot touch the headers and burn up even with the plug boots on them. Do u know if these are good plugs? hope so they are 30 bucks im putting them on now