Two questions about crankshaft dynamics

[JamesMcDonald]

Question 1:

Is there a relationship between firing order and the location on the crankshaft from which the drive is taken (front, rear, or middle)? (Would/should the BRM Type 15 V16 have had a different firing order if it had had a "normal" crank with the flywheel at the rear of the engine?)

Question 2:

For a "longish" engine which might struggle with crankshaft twist, would it make any sense to design in a shaft running parallel to the crank, geared directly to the crank's extremities, to absorb or prevent some of the crank's "desire" to twist? Or is torsional crank distortion generally so minimal that it would not make it past the mesh of the gear teeth? (I have read of cams twisting enough to affect valve timing.)

Thanks,
James

 

[GregLocock]

1 yes
2 you'd be better off using one of the more usual solutions. Crank vibration often exceeds 1 degree, i don't know how much static torsion you get on top.





Cheers

Greg Locock


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