A few years ago, before I was selling HKS parts, I remember paying over £100
for a set of (6) HKS plugs for my supra....that was painful http://www.lancerregister.com/graphics/Wilk.gif border|EQU| 0 align|EQU| middle >
Yes, £14.50|PLS|vat each...ROFL.
Still worth it IMHO considering the job they do.
I run HKS S40's (grade 8) , boost 1.55 and runs perfectly.