Sorry, somehow this one got by me.
The '86 engine is a one-piece rear main seal. So, you will need a 153-tooth 2-piece rear main seal flexplate. I've seen good new ones for around $25.
The '86 damper (it's not acutally a "balancer") probably isn't a good idea for 2 reasons: 1) It's a 305 damper, and 2) the '86 timing tab is at 12 o'clock and the '77 is most likely in the 2 o'clock position. Better to go out and get a 350 damper.
A '77 350 4-bolt probably came out of a truck. Since the dipstick will be on the driver's side, the '86 pan won't fit. Whether the stock '77 pan fits in the 3rd gen, the answer should be "yes", but there are possible variables that can't be known simply by saying "77 350 4-bolt". As long as the basic shape is the same as your stock pan, you should be okay. The point where it starts dipping down to the sump is the key factor.
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Quote:
Originally Posted by F-BIRD'88  If your old 305 had center bolt style valve covers it may be a one piece rear main seal block. If it has the old style perimeter bolt valve covers its likely a 2 peice seal block. |
'86 was a "bastard" year. They were perimeter bolt valve cover, flat tappet cam, one-piece rear main seal.
