I put Bosch plugs in my stock '89 at about 20k 'cause I didn't want to change them often. I now have 70k on it, and have had no problems.
Keep in mind I don't run it hard or race. It's just plain 'ole stock as it came out of the box.
------------------
'89 LX 5.0 - Original Owner
'94 E-150 Conversion Van
|