Oversize Inconel exhuast valve for all 4v VW/Audi motors including 16v,20v and 32v motors.
Back cut valve head and stem greatly increase flow, we've seen up to 15cfm just from dropping these in an otherwise stock head. Bonus is that these valves work with high quality OEM seats which are cast into the head, so no valve seat change is necessary.
Fit with OEM seats, use with OE fit springs, retainers, guides, clips, etc. OE seats need to be cut to the new larger diameter, otherwise a direct fit for stock.