STANDARD FLYWHEELStandard Transmission Flywheel for 400 SBC External Balance for 12 Clutch.Fits : 1978 GMC Light Trucks Suburban 8 CYL, 6.6L, 400CID and many other applications.14.125 OD, 168 Teeth, 30Lbs Fits 70 - 72 Chevrolet Chevelle, 70 - 72 Chevrolet El Camino, 70 - 72 Chevrolet Monte Carlo, 78 - 80 GMC Light Trucks Jimmy (Full Size), 78 - 80 GMC Light Trucks Pickup (C, K, R, or V), 78 - 80 GMC Light Trucks Suburban Please call if you are unsure of fitment.