Originally Posted by dusterbd
ok, so ive got a 73 vintage 350 in my project. codes came back as a truck motor with a 3 speed behind it.
at some point it was freshened. unknown to what extent. runs good, sounds good, checks out healthy. pretty strong, too.
anyway, i converted it to serpentine accessories. in the process, i discovered that the harmonic balancer has 3 nubs sticking out in addition to the three pully bolt holes. ive never seen this. nor does any of the aftermarket pullies support this. all of them only have the 3 bolt holes. i drilled my serpentine crank pully to account for them, but it now does not run true. dont know why. planning on clearancing the holes a little more, and seeing if i can get it to self align.
makes me wonder just what the balancer is off of.
also, makes me wonder if i can grind those nubs off. make it so i can run an unmodified pully.
what do you small block guys say? im kind of baffled here.
Wow an old one, Chevy just used a pressed on damper years ago except on performance engines. There is a kit that most decent parts stores stock that has a 7/16ths x20 x1.5 inches bolt a thick washer and sometimes the correct tap to thread the tooling hole in the crank's snout. Good insurance. The nubs on the back of the pulley are there just to hold it aligned to the damper. Older dampers don't have the mating feature, so newer pulley's can have this ground off, or the old damper counter-bored to accept them.
Frankly, I'm not that enamored with serpentine belts that I would've spent good money that can be used to better purpose elsewhere than to play around with the accessory drive.