Howdy HAMB'ers, Need some info. Swapped a crank from a '9? LT-1 truck motor that had the long skirt (heavy duty) pistons (NOT a Vortec engine) into a '97 LT-1 truck with Vortex heads/pistons and am now suffering a vibration. Research revealed the two cranks carry the same casting number and appear identical, however, they are balanced differently (both have the powdered metal rods). I'm looking for either a way to visually ID the different units, OR, better yet, come up with the bobweight specs for the two cranks so I can confirm the proper crank goes back in. Anybody familar with this issue? Thanks ahead for any help, Waldo
Why not just have the current parts rebalanced ? Not that expensive, and will give a better outcome than factory parts.....
rotating assemblies are usually balanced as a whole unit so just because you have 2 of the same crank does not necassarily mean they are balanced the same could have had a heavy rod on 1 setup so the crank was balanced different for that setup, as far as bobwieght specs sorry man cant help you try pickin the machinists brain
You get your bob weight specs by weighing the pistons, rings and inserts. Every engine combination is different. Around here it would cost you about a buck and a quarter to get it ballanced. As has been mentioned take your pieces to the machine shop and get 'er done.
thought lt1 style took a different style balancer / crank hub or what ever it is.... normal newer style 350 (non lt1) have that nuetral balancer with a weighted flex plate
Ok, for one thing there is no such thing as an LT1 truck engine. They were never used in trucks. They came in 92-96 Corvettes, 93-97 F-bodies (Camaro/Firebird), and 96-96 fullsize cars (Caprice, Impala SS, Roadmaster, Fleetwood). That said, the stock crank in an LT1 has sort of a "hybrid" balance...neutral front/external rear. What trans are you running, and what flywheel? LT1 cranks aren't keyed (they have a keyway in the crank, but no key for the hub), which is one way to ID. I can pull one out of my storage unit and take a pic if you need it. Either way, the flywheel should be weighted for external balance.
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