I've decided to share.
What follows are the optimal engine sizes for each tonnage of chassis (assuming endosteel).
The way this works is I graphed speed vs free tonnage for all mechs and all engine sizes, then I found the places where each mech tonnage had the most free weight for a given speed range.
Or in other words, if you've got a bigger engine than those listed below, you would gain a small free tonnage advantage by going to a lighter chassis at the same speed. Similarly if you're using a smaller engine than those listed below you'd gain some free tonnage by going to a heavier chassis and keeping the same speed.
An interesting thing to note is that some chassis have more than one range, due to the engine weight progression. 20Tonners for instance are worse off than an equivalent speed 25tonner if they use a 205Std engine, but are better off with both the 200Std and 210Std.
Std Engines
20Tons: 190-200, 210-255 (note with a 255std and endo, you have no armor/weapons)
25Tons: 230-235, 255-260
30Tons: 250-270
35Tons: 260-285
40Tons: 270-295
45Tons: 275-295
50Tons: 280-300 (yes, this means hunchbacks have crap speed)
55Tons: 285-305
60Tons: 290-305
65Tons: 295-300, 310
70Tons: 300, 315, 330 (70tons is a weird place for Std engines+endo)
75Tons: 325-335
80Tons: 325-340
85Tons: 325-340
90Tons: 335-340
95Tons: 335-350
100Tons: 100-350
XL Engines
20Tons: 245-325 (note with a 325xl and endo, you have no armor/weapons)
25Tons: 265-300
30Tons: 280-310
35Tons: 295-320 (this is why non-3L Ravens suck so bad)
40Tons: 300, 315-330
45Tons: 330-350
50Tons: 335-360
55Tons: 340-360
60Tons: 345-365
65Tons: 350-370
70Tons: 350, 360-370
75Tons: 350, 360-370, 380
80Tons: 360-370
85Tons: 365-370, 380
90Tons: 380
95Tons: 380-395
100Tons: 100-395
*note* I have included lower rated engines which share a weight with higher rated engines due to MWO having engine caps. Obviously a 255XL is better than a 250XL as they both weigh the same, but in the future there may be mechs with an engine cap of 250.
If you go by how much tonnage you want to put into weapons/armor, you get the following chart of what tonnage of mech to use:
Std:
0-4: 20t
4.25: 25t
4.75: 25t
5.5-6.5: 20t
6.75-7.25: 25t
8-10: 30t
10.75-13.75: 35t
14-17.5: 40t
18.75-21.25: 45t
22.5-25.5: 50t
25.75-29.75: 55t
30.5-33.5: 60t
34.25: 65t
35: 70t
36.25-37.25: 65t
38: 70t
38.75-40.75: 75t
41: 70t
42.45.5: 80t
46.75-50.25: 85t
51-53: 90t
53.75-57.75: 95t
58.5t+: 100t
XL:
0-7: 20t
8.25-10.75: 25t
11-14.5: 30t
14.75-18.25: 35t
18.5-20: 40t
20.75-22.25: 45t
22.5: 40t
22.75-23.25: 45t
24-27.5: 50t
28.75-31.75: 55t
32.5-35.5: 60t
36.25-39.75: 65t
41-43: 70t
43.75: 75t
44.5: 70t
45.75-47.75: 75t
49.25: 75t
50.5-52.5: 80t
53.25: 85t
55.25-56.25: 85t
58: 90t
58.75-62.75: 95t
63.5+: 100t
If you want which size of chassis to choose by preferred speed (pre-tweak), use the following chart:
Std:
16.2-56.7: 100t
57.126-59.684: 95t
60.3-61.2: 90t
61.941-64.8: 85t
65.813-68.85: 80t
69.429: 70t
70.2-72.36: 75t
72.9: 70t
73.532-74.769: 65t
76.371: 70t
77.262: 65t
78.3-82.35: 60t
83.945-89.836: 55t
90.72-97.2-50t
99-106.2: 45t
109.35-119.475: 40t
120.343-131.914: 35t
135-145.8: 30t
149.04-152.28: 25t
153.9-162: 20t
165.24kph-168.48kph: 25t
170.1kph+: 20t
XL:
16.2-63.99: 100t
64.8-67.358: 95t
68.4: 90t
69.565-70.518: 85t
72.424: 85t
72.974.925: 80t
75.6: 75t
77.76-79.92: 75t
81: 70t
82.08: 75t
83.314-85.625: 70t
87.231-92.215: 65t
93.15-98.55: 60t
100.145-106.036: 55t
108.54-116.64: 50t
118.8-120.6: 45t
121.5: 40t
122.4-126: 45t
127.575-133.65: 40t
136.543-148.114: 35t
151.2-167.4: 30t
171.72-194.4: 25t
198.45+: 20t
Edited by One Medic Army, 01 May 2013 - 05:58 PM.