Ah, Support Golems, how I love thee. Time after time I see people somehow overlook or even discount them, because it "just" has a missile launcher for its heavy armament.
It's an ASRM6. With six shots. That's 180 missiles per Point. That's more lethal than a shark with a fricking laser on its head!
And all in a 18 point fire resistant shell that moves 2 MP.
What I found with Ogres vs Cuchulainns (or Ogres vs any other non-fire resistant suit for that matter) is that it all depends upon when you kill that first Ogre. If the Clanners can use their range advantage, then they have a chance to get a kill before the Ogres get to shoot. Even once the Ogres starts shooting, there's still the issue of regular-skilled troopers needing 11+ at long, so really the IS suit needs to get to medium. All that gives the Cuchulainns the time to get that all important kill.
Assuming average Cluster Hit Table rolls, then worst case, the Cuchulainns will get that first kill in the third salvo that hits, and best case it will take them one salvo; either way, all the Ogres will be dead after the forth salvo hits if the Cuchulainns take no more than one loss. Depending upon terrain and whether there's freedom to maneuver, they could get up to five turns of unanswered fire, with an additional three turns where the Ogres are at long. If the Cuchulainns are fixed in place, then it's two turns of unanswered fire and two with the Ogres at long range, assuming the Ogres play smart.
All this assumes that the Ogres don't suffer losses due to their Infernos exploding after a hit. Remember kids: it can be unsafe to play with Infernos unless you're in a fire-resistant suit.
If the Ogres are a suit down before they start achieving hits, then it's almost certainly game over for them as they won't have the numbers to hit with three Infernos per Turn unless they get very lucky on the Cluster Hits Table. You can shoot a squad or Point of battlesuits with one or two Infernos per Turn all day and you'll do nothing. You must have at least three hits to actually start killing anything. Obviously, once two Ogres are down, then they're better off retreating as they then have zero chance of killing a Cuchulainn.
On the flip side, due to their larger unit size, the Cuchulainns can suffer a single casualty and still be hitting with an average of three ERMPLs per salvo, enough to one-shot an Ogre if they're lucky enough that all three hits strike the same suit. Even when down to one remaining suit, the Clan unit remains dangerous and potentially could win a Pyrrhic victory.
If you have more than one squad/Point per side, then the Ogres can take losses and still achieve the all important threshold of three Infernos per turn, but in return the Cuchulainns will be killing them quicker. While the Clan suits are almost guaranteed to take some losses, they should still come out victorious more often than not.
