External Balance Engine with Neutral Balance Converter?

[Thanatos340]

I found a fairly good deal on a Crate 408 Short Block to replace my 340 that recently took a dump on me that I am very seriously considering.

The Crate engine is using a Scat externally balanced cast crank. Since I already have a new Neutral Balance 3000rpm converter that was for my 340:

1. Can I just use an external balance Flex plate like a B&M 10239 and my existing Neutral Balance Converter or would I need to send the converter out and have weights added to it as well?

2. The Crate engine calls for a "Magnum" weighted balancer. Is this different than a 360 "LA" weighted Balancer? I have a couple 360 "LA" balancers laying around but nothing that is for the Magnum Version.

 

[TrailBeast]

Flex plate swap is the best solution for now, AND if you ever swap converters use can use neutral balanced in the future.

No weights needed anywhere else. (just the balance plate)

Not sure on the 360 using the same one as a magnum does.

 

[Locomotion]

360 Magnum uses a different balancer and converter weight than the original LA 360. Magnum weights are less.

 

[trapster]

Just curious but would stroking an engine change the balance needed ?

 

[Locomotion]

Yes, pistons tend to be lighter and the weight is being swung further out due to the stroke. But it doesn't necessarily cancel each other out and any such change needs to be checked by a competent shop that balances engines.

I don't know what they do with crate engines, but it appears that they come with balancers/dampers and one should go with their recommended converter/flexplate weight.

 

[pishta]

Stroking a motor alwys affects stock balance. Shorter lighter pistons, throws that are farther out generate more force, and the cranks can be forged or cast and usually have a different bob weight to begin with.

 

[67Dart273]

360 Magnum uses a different balancer and converter weight than the original LA 360. Magnum weights are less.

^^THIS^^ If the crate specifies "magnum balance" then you need to use the magnum components. Or to put it another way, whatever the engine builder specifies, both balancer and flex / TC or flywheel

 

[trapster]

That is what I thought, so the answer to this question, ask the builder.