I have a 99L with a 4#er, ProM80, and chip. I'm currently having a spark knock at WOT and want to buy better plugs that will hopefully cure the situation or atleast help it out. I;ve read several posts about people using IT22's but I went on the Denso website and it said that a 99L needs IT16's? Havnt seen any posts about IT16's and was wondering which ones I should get.

Also where is a good place to buy them from?

thanks in advance for ur responses

 

I've got IT-20s gapped at 0.032" with no problems.

Rich