Quote:
Originally Posted by classicauto
I've done a couple different styles of jacket mods, run a high flow (REmedey) waterpump, and use 10 and 10.5 plugs (NGK 7420). Still haven't needed to build my next engine to try the additional web or bridge or heat sink (chunk of AL inserted diagonally in the leading plug cooling passage on both sides of it) out. But I'm not exactly disappointed that I haven't needed another yet 
Currently floating around my mind are the idea previously mentioned, as well as running higher system pressure. Much higher. Also, Barry pointed out some NGK surface gap style plugs which appear to perhaps retain less heat given their tip design vs. the 7420's. |
Classicauto, have you measured the gap of the surface gap plugs?
This may be a problem, they may be a little large for boosted engines.
Also it would be nice if they were made of some rare earth metals like platinum or iridium.
Barry