Hays Twister Full Race Torque Converters feature a custom designed anti-balloon plate to stop any converter ballooning and swelling in racing situations. These torque converters are designed for use with a trans-brake and great for power adders such as nitrous, superchargers, and turbos. They are available with various RPM stall speed offerings to accommodate any mixture of modifications including higher compression ratios, aftermarket camshafts, aftermarket cylinder heads, lower gear ratios, and vehicle weight loss. Utilizes 7/16"-20 flexplate bolts (Not included).