Can't find my archived post, but the math's fairly straightforward. Here's the breakdown:

Base warp speed:
Borg: 14
MACO: 12
Everything else: 10
Slipstream: 20

Driver coils is a (skill/2)% increase, but can't break the warp 10 barrier with most engines. At 9/9 you have 99 skill, or a 49.5% increase to warp speed. MACO engines have a boost to driver coils, 8.8 on the mk XIIs. So now the base speeds (MACO assumed to be mk XII):

Borg: 20.93
MACO: 18.47
Other engines: 10
Slipstream: 29.9
Slipstream with MACO: 30.78


Ok, figuring average speeds, you have to consider how often you slipstream. Slipstream lasts 30 seconds (60 on the Odyssey), and starts a 2 minute cooldown at the end. OMEGA engines drop the cooldown to 1 minute.
So, our averages (9/9 driver coils, MACO again assumed XII, also assuming you can manage perfect uptime on slipstream).

Non-Odyssey ships:
Borg: 22.724
MACO: 20.93
Omega: 16.633
Everything else: 13.98

Odyssey
Borg: 23.92
MACO: 22.573
Omega: 19.95
Other: 16.633

So, basically, your best bet is an Odyssey with Borg engines.


Diplomatic Immunity and Raiding Party are tempoary buffs that you have to get from somebody else - even if you have tier 3 diplomacy/marauding, you can't give yourself the buff, only other people. You can still enter enemy sectors, but don't get the warp speed buff.

They go away after time, or if you leave sector space. Their current form according to tooltips is a +50 buff to driver coils, bringing us to 149/2= 74.5%. With this, our speeds are (same assumptions as above, note omega and other engines are still capped at 10, but you do enjoy the buff to slipstream):

Non-Oddy:
Borg: 24.43, Slipstream 34.9, average 26.524
MACO: 21.468, 35.78, average 24.1544
Omega: 10, 34.9, average 18.3
Other: 10, 34.9, average 14.98

Oddy:
Borg: 24.43, Slipstream 34.9, average 27.92
MACO: 21.468, 35.78, average 26.238
Omega: 10, 34.9, average 22.45
Other: 10, 34.9, average 18.3