Join Date: Sep 2000
Location: Charleston,S.C., USA
GM# 3896966 (302 73) Harmonic Balancer
I have recently purchased a 350 SBC motor and based on the following info,
VO511CKW, 3970010 block, I felt it was a 350. I have removed the oil pan and timing cover looking for additional supporting numbers. So far without removing the crank and a pistons, the only numbers I have found are on the harmonic balancer is #30 stamped on the top of each piston and GM# 3896966, 302 73, 2222H on the balancer. Even this is somewhat confusing as I have seen this # 3896966 balancer listed for use on early 67 SBC 302's (internally balanced motors) and for use on SBC 400's (externally balanced SBC's).
1) Is the above 3896966 balancer an internal or external balanced damper? There are only two (2) drilled balancing holes on the back. There is no fat side thin side that I have seen pictures of on other 400 SBC balancers.
2) Where would the GM part # be located on the crank shaft and pistons/rods (if it's factory.
This motor was overhauled 5 years ago so I'm sure the pistons and rods may be replacement, at least the piston tops.
I'm trying to determine if this is really a 350, or is it a 400. So far the only part I have purchased and may not be able to use is a replacement harmonic balancer that I purchased for a 350 SBC.
Because of the internal / external balancing issue I'm at a stand still. I hope I can avoid a machine shop, but that still might be required just to figure out what type motor I have in hand.------ HOPING I HAVE A 350!-------
All replies and info would be of great help and appreciated. Thanks for all replies ahead of time.
John Lighthart Jr.