I dunno, but my experience echoes yours-I bought a used tach cluster for my 64, the tach seemed very slow at first, then quit altogether. Not sure whether it was due to the HEI or just moivng again after many years of non-use. Brian


My \'64\'s in the Gallery
Pictures in my Photobucket
1964 C10 Custom Cab 350/700R4
1964 Suburban 350/700R4
1979 Ford F350 4x4 400/c6