Loading Gearbox: 1432 or 1-3-2-4 Firing Order?

[wolram]

If 2 twin cylinder engines are geared together (90 degree cranks) and then a chain is coupled to the rear engine to a gearbox, would it be best to have a 1432 or a 1 and 3, 2 and 4 firing order,1 being front engine left 4 rear engine right ,to give least load on the gearbox, intuition tells me 1432 would be best (the load is spread) evenly, but would the main shaft bearing have a reduced life time.

 

[FredGarvin]

I assume you are talking about the dynamic loads from the engine, not the transmitted power from the shaft? An educated guess would be option B which would have more of a dynamic balance to it.

Your main shaft bearings are journal bearings, correct? I can't see how you would have reduced life unless the coupling of the two increases the radial loading. Is there an option to increase oil pressure slightly?

 

[wolram]

There is an option for an uprated bearing but it requires some crank case mods, so i am not sure if it is justifiable, i may be able to increase pressure with an uprated oil pump, yes they are journal bearings.

 

[nucleus]

I don’t know what you are doing but the following site has a lot of information on the subject of joining engines to gearboxes. The section on Mechanical Basics and Piston Engine Technology are especially good.

http://www.epi-eng.com/piston_engine_technology/engine_technology_contents.htm

I don’t know the company but I see they have software to help match engines to loads.