how to tell what year 2.8 I have?

[Ramblin Man]

I bought a 2.8 liter fiero motor for a swap I'm doing. However I need a flywheel and the previous owner was not the original owner and does not know what year the motor is. Is there a block casting or crank casting I can use or some other easier way to tell what year motor I have? The 88s were internally ballanced but the 87 and older fieros used an ballanced flywheel so I need to know what to buy.

[geoffinbc]

Check the rear main seal. 2 piece denotes external balance on piece is internal balance. Or remove the oil pan. If you see a reluctor wheel it is internal balance. No wheel means external balance.

[sharkey]

im gonna disagree with that. the 2 peice rear seal was used 80-85.5 with the small journal crank. 85.5-87 was an external balanced crank, 88+ was internal balanced. balancing was done on the flywheel only, the damper was neutrally balanced

[geoffinbc]

Yea your are correct I goofed on my facts. A one piece seal denotes large journal and a 2 piece or rope seal denotes small journal. The only external tell tale sign is the flywheel/flexplate. All internal balance engines will lack the large balancing mass on the back of the wheel. If the flywheel/flexplate is missing then the reluctor wheel on the crank is the give away.

[ForcedFirebird]

RWD motors don't have a reluctor wheel, it's just a blank circle. I thought the holes drilled in the couterweights was the balancing. Either way, the rear seal is the best way to tell unless somebody bored the block to accept the larger journal crank (ARI does this on their strokers).