Your 1983, 350 is internally balanced and uses a two piece rear seal. Where the 350 is concerned, reference to external balance is aimed at the 86/87 and up engines with a one piece rear seal where reshaping the flywheel/flexplate mounting flange forced a small amount of balance weight be placed externally. This is nothing like the 400 or options on stroker cranks like those of the 383 where a much larger portion of the counter balance is carried on both the flywheel/flexplate and the damper rather than just the crankshaft's counterweights, these are truly externally balanced, but can be modified to internal balance for enough bucks.bwomp969 said:I'm looking to rebuild my 1983 350sbc and I saw on jegs.com that their kits are "internally balanced" and "externally balanced" whats the difference?
what do each mean?
You need to know where your 383 is starting from, stroker cranks and kits are sold in either external or internal balance. If you get it wrong the engine will shake from being a major annoyance at the minimum to perhaps coming apart at the maximum.79monster said:I have a 383 does that mean im supposed to be externally balanced? do i buy proper flywheel/damper combo? if i dont what could happen?
79monster said:so if i have a stock 400 crank @ 3.75 stroke in a 350 then i should be ext. balanced and if i buy a kit i should get it int. balanced? is there advantages to either?