Reply to "Stroker engine vibration"

OK - my engine appears to be internally balanced - that explains why it was shaking when I put on the 28 oz flywheel.

The harmonic balancer on the engine (which is the original)is for internal balance. It's a proffesional products balancer - 80006, http://www.summitracing.com/parts/PFS-80006/?rtype=7 that can be used for either 28.8 external or internal balance.
Mine doesn't have the weight on so it's neutral balance and thus the crank must be internally balanced.

Also, the crank appears to have what could be mallory metal (??) welded into one of the holes on the first through (picture). A normal procedure when balancing internally - I think.

RPM makes 4340 stroker cranks for 427 winsors with either internal or external balance. I'm waiting for RPM to get back to me on which crank it may be (I have a part of the marking on the first through of the crank).

If it's true that it's internally balanced, then I'm really upset. The engine came with 2 sheets outlining all the parts that wen't into the build. I used those to determine that the engine was externally balanced and based my flywheel purchase on that.
Now it turns out that the actual parts in the engine (crank, rods, pistons, harmonic balancer and flywheel) are different to what's stated in the papers !! I may have ended up grenading this engines based on this misinformation.

The rest of the parts in the build sheets that I can confirm appears to be correct.

The builder is out of business now, so it doesn't make sense to warn you about them. They were building a lot of strokers a few years ago, so maybe they just copy pasted a reciept from a previous build without paying attention to what really when into the build. NOT OK.



Kristian