Dinan's Free Flow Exhaust for 645 models provides improved flow and the resulting power gains without the excessive noise and ''boominess'' associated with typical after-market mufflers. The mufflers feature ridged and durable cases, manufactured from 100% 20 gauge-304 stainless steel inside and out for optimum resistance to corrosion. Internally, the systems feature Dinan's Tuned Resonance Chamber Technology, providing the optimum balance between maximum power gains and a civilized, yet sporty exhaust note. 3.5 inch diameter polished stainless tips give the cars a tasteful performance look as well.?
*Dyno results for the combination of the High Flow Intake System, Stage 2 Engine Software and Free Flow Exhaust.