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Author Topic: Voluntarily using an engine of higher rating than necessary  (Read 352 times)


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TM, 4th printing, pp. 48, 100, respective sections called "Install Engine"

May a unit voluntarily use an engine of a higher rating than necessary? I have found no rule explicitly forbidding or allowing it.

Background: For example, I want to regularly use a 55 ton, 5/8MP tracked tractor combined with a 15 ton trailer. Normally, the tractor would be built with a 275 rated engine, giving the tractor/trailer combination a speed of 3/5. By using a 280 rated engine, the combination could move at 4/6 MP, while the tractor alone remains unchanged except for cost and lost free weight.
Another reason might be to standardize on some engine ratings for spare parts in campaign play or - from an in-universe point of view - to utilize an already existing engine production.

Units may voluntarily forego using some weight capacity
TM p. 18:
UNUSED WEIGHT Even if the completed unit falls short of this target weight, once completed, the unit must be considered to have achieved its target weight for purposes of game play performance and transport weight. Unused weight is either “lost” or treated as cargo (if the unit’s construction rules so permit).

Units might leave engine capacity unused due to rounding
TM, p. 100f:
Also, if the Engine Rating attained  is not evenly divisible by 5, the designer must round the result up to the nearest Engine Rating.

Hovercraft may use engines heavier than necessary for movement
TM, p. 101
Hovercraft Combat Vehicles have a minimum engine weight [...]. If the desired movement rates and the vehicle’s tonnage would result in an engine that weighs less than this minimum, the engine is automatically increased in weight - but not performance - to meet this requirement.

Frankenmechs may use engines larger than necessary
Campaign Operations, 2nd printing, p. 213: 
[...[ engine [...] there are no restrictions on its type and rating[...] as long as it grants at least one Walking MP to the final ‘Mech.
"Divide the engine rating by the maximum tonnage and round down to find the Walking MP.

If it is possible to have "overrated" engines on an ad hoc basis, it should also be possible to do it in standard production.

Thanks in advance!
*"But we don't play Battletech to have Simple" - NavPoint

I'm willing to suspend my disbelief, but I'm not willing to hang it by the neck until it's dead, dead, dead!