My 98 is a V6 but still the platinum tips are pre set ??? to .060 out of the box and from the factory thats why I questioned the .600. The highest gap I have seen in my experience was .120 on my 96 Northstar in a STS . And even at that rate my lil V6 is plug picky it does'nt like the copper electrodes at all. I guess I'm still comming to grips with paying $6.50 for a single plug!!!!!!