Posted 31 October 2017 - 06:57 PM
(this was from an early/mid 80's FASA battletech rulebook, 2nd ed I think, but I'm working from memory because I no longer own it)
For TT Cooling was done very simply.
Each round, you added up the heat you generated by firing weapons (var., ofc), moving (walking was 1, running 2, jumping 3), and any heat left over from previous rounds. Then you subtracted from that total the number of heat sinks your mech had (doubling any HS that happened to be submerged). If the number was 0 or less, you had no heat for the round. If you had more heat than cooling, you had an amount that might give you a penalty for the next round (<4 was no penalty iirc, then stuff started to happen).
Single heat sinks counted for 1 each, doubles for 2. I'm too fuzzy to remember how engine HS were handled, but I do recall you could have a mix of singles and doubles as externals (though that may have been a house rule we used, but there is no logical reason not to do so) (doubles, btw, didn't show up until the clans came on the seen, which was a little later than the original rules I had)
(oh, also flamers and inferno round could add to your heat that round, or enviro effects)
As far as engine heat sinks, that seems to have gotten muddled . Basically, in MWO terms, you treated every single mech/engine as if it were rated 250 (10 built-in sinks, also called internal heat sinks). So, a Locust with a 190 rated engine had 10 built in HS, as did a Victor with a 350.
The internal heat sinks with each engine were, effectively, weight free (just as they are in MWO, but always 10).
I recall two engine weights. A standard 300 weighed 19 tons (that was a rating that got used all the time). I've tried to reconcile the engine weights of old with MWO, but since they've rolled in the gyros and what-not, working from memory has made that difficult (gyros, btw, used to weigh engine rating div/100, round up, so a 200 rated engine had a 2 ton gyro, 205-300 3 tons, 305-400 4 tons, etc.) I think base sensors, life support, etc, also weighed 3 tons for every mech (so, 3 ton sensors/life, 3 ton gyro, plus a 300 rated std engine would be 25 tons, which is what it is in MWO, Hmm. Engines in mwo might just be gyro+sensor/life+engine.)
I think a std 400 weighed 52.5 tons? In MWO it is 59.5 (which would be the 3 tons sensor/life and 4 tons of gyro plus the engine).
Engine tonnage was NOT a linear table. Engines above 300 rating got much heavier much faster.
If I could remember a <250 rated engine weight I could confirm or deny the -1 ton per heat sink missing from the 10. Given the -2.5t weight for a 60 rated engine, that may be accurate though. So perhaps lights wouldn't get a boost from the 10 hs thing.
Btw, the rules I recall only allowed exact tonnage multiples for a mech's engine (so, for example, a 45 ton mech would never have an engine rating of 260 because it wasn't an even multiple of 45 tons: 45, 90, 135, 180, 225, 270, etc.). That was just because of how hex based movement worked in TT though.