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Inline 6 crankshaft balancing

Practical Engine Building

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Hi there, in an inline 6 engine do I need to balance the crankshaft with the front pulley, flywheel and clutch installed together even if each of the components are individually balanced from the supplier?

I am building a 2JZ and will be using a PMC flywheel with tilton clutch. For the front pulley I may use stock or go with a Titan pulley.

That is normal practice. even when parts are individually balanced. A couple of reasons are -

As each part is balanced, they won't be perfectly balanced, but within a tolerance, or acceptable limit, and while these may tend to cancel out each other, there is an equal chance they will add up - sometimes called accumulating, or stacking, tolerances - and it could end up being out of tolerance for the full assembly. There is an added problem in that some manufacturers are rather slack in their manufacturing and quality control and some don't even balance their product, like most pulley makers. On that, I would recommend you use a GOOD damper and not rely on the OEM one.

With some engines, the final balancing is done by removing material from the front pulley/balancer and flywheel, if so, unless the replacement is similarly made 'out of balance' in the same way, it will actually throw the balance of the complete assembly out with a perfectly balanced replacement.

Re: your other post on machining, same comments apply regarding options to get the engine work done.