The 98 SVTs (E0 and E1) upper intakes are "single Extrude Honed"..1 pass through the gritty porting procedure.
99 & 00 SVT are "dual Extrude Honed"..slightly larger smoother runner ports.
Demon SVT has "triple Extrude Honing"..he sent it back for more. Why? Because the SVT intake ports and lower intake are about 34-35mm (secondaries) and the dual Extrude Honed upper is only about 32-33mm. He just got everything the same diameter for optimal flow..especially useful since he removed his butterflies.
I think more Extrude Honing is probably useful ONLY with lots of other mods..bigger MAF meter, filter, possibly t.body, possibly removed butterflys & a good free flowing exhaust system.
