Lighter flywheel easier on gearbox?

[SteveS]

I know a lighter flywheel doesn't lower torque, but would it be "easier" on a transmission? In other words, with an engine whose torque rating exceeds the transmission's torque rating, would a lighter flywheel (less inertia) make it less likely that the transmission will break?

 

Thank you,

Steve

[xcarguy]

Steve,

 

I'm running a lightened flywheel on the Storker. In short, the reduced rotrational mass helps the engine rev faster. Flywheels are basically energy absorbing/storage devices; the heavier the flywheel, the more of an engines energy (power output) it can store for longer periods or time. If an engine produces x lb-ft of torque, the time it takes that engine to produce (rev up) and deliver its available amount of torque can be altered (reduced) through the use of a lighter weight flywheel. This is great for high performance driving, but not so great for the street. Having said that, if an engine's torque output exceeds a transmission's torque rating, lightening the flywheel may very well result in exceeding the transmission's torque rating much sooner. However, I wouldn't recommend using a transmission that isn't rated for the engine's torque output regardless of flywheel application. These articles may be helpful: :cheers:

 

http://www.uucmotorwerks.com/flywheel/how_a_lightweight_flywheel_works.htm

 

http://www.uucmotorwerks.com/flywheel/there_is_no_torque_loss.htm

 

http://www.torquecars.com/tuning/flywheel-lightening.php

[SteveS]

Thanks a lot. I see what you mean now by a lighter flywheel actually actually being worse for a lower torque rated transmission (as the torque comes on more quickly I believe). The articles were helpful too.

 

Steve

[bsimon]

One place the lightened flywheel really shines is in conjunction with a dog engagement gearbox. The engine decelerates faster when you lift the footfeed to allow faster and smoother clutchless shifts, be it a sequential or H-pattern 'box. The engine spools up or "blips" faster for clutchless downshifts as well.