could a pack of yanghuanosaurus take a spino?

Personally, I think that this particular Spino would win, and here's why:  you said he's abnormally aggressive, and the bachelor pack of the Yang are highly experienced.

If the Spino is abnormally aggressive, than he's more than willing to fight anything.  It could be that it would be breeding season, or even more than that, this male could be in a state of musth, or the dinosaurian equivalent.  Bull elephants in musth basically scare off everything except eostrous females, and have very short tempers.  They even scare off larger males who aren't in musth.  Bottom line, this particular Spino is more than willing to pick a fight with anything that bugs him in the slightest.

The male Yangs, who are experienced, would be able to tell that this male Spino is a serious threat with a severe attitude problem, so the best thing to do is to avoid him at all costs.  If they do happen to attack, the Spino's ferocity would likely kill a few members of the pack, and the rest would be so scared of this psychotic giant that they'd run away and save their own hides rather than die trying to take him down.

On a side note, I'm intrigued that you'd make the Yang pack with only fully-grown males.  Usually it's a pack of sub-adults or a gang, or even a family pack.  You made the pack like a coalition of male cheetahs, which is rare when we talk about dinosaurs.  I like that "thinking outside the box" hypothesis.

I would say Spinosaurus,a nd my reasoning would be similar to the reasoning of AlphaDino65. Interesting though, why would a pack only consist of males? In some species, like lions, the females are the hunters, and he males are actually quite lazy.

I'd say Spino for reasons already stated above. In a pack of 6 members, losing two is pretty big. That's a third of the group. 

Just realized something. Last time something like this was done (six of one predator vs one large predator, Utahraptor vs T-Rex), we had something like 140 or more responses with varying opinions, even in the first four posts. That's six half ton predators vs a seven or better ton predator. So, with that, here's the different opinion. 

It's entirely possible for the Yang pack to have won. That's six predators that weigh 4.5 tons and are well equipped for taking down creatures larger than themselves. 4.5 times 6 is 27. Spino weighs 10 tons in this case. Spino is outweighed by 17 tons. Yangchuanosaurus had the agility advantage, the equipment to take Spino down, the numbers advantage, pretty much everything but sheer size. The Spino is easily pissed off, so if anything, that would hinder him because he'd swing every chance he got as opposed to picking his attacks, taking only the good shots. 

Before anyone says anything about me "underestimating Spino" in this situation, I think any lone predator, be it Spino, Giga, Carchar, or Rex, would be screwed against a pack of six Yangchuanosaurus. 

Us I agree with mr.happy. 6 yangs each weighing 4.5 tons and 33 feet long . Highly experienced. That pack would be highly powerful.. And the yangs are in a bachelor group like lphadino pointed out.the spinosaurus is indeed in his musth but the spino could not handle six predators each half it's size no matter how big the spino is. The spino will lunge for the poor yang closes to it and while it is tearing it to shreds, the other 5 yangs will leap into the spinos sides and weigh it down and then maul it to death.......

I'd say Spino, as he would kill two or three and the rest of the pack would run off. However, the pack could land some serious wounds to the creature.

I'm gonna give this one to the "Yangs." If there were only 2 or 3, I'd give it to Spino, or at least give it better odds. But Yang was a pretty robust and strong allosaur and with 6 of them in a fight, that'd be a force to be reckon with. I'd say 55-45 in favor of the Yangs, maybe 50-50 if the Spino is really ticked off.

Mr Happy speaks of another valid scenario.  But only if the pack decided to attack the Spinosaurus, and that would mean that they'd be extremely desperate, such as in times of drought.

If each male Yang is experienced, than they'd know that taking on a musthing male Spinosaurus would be too much of a risk for them.  Yes, they could bring him down, but it would be crazy to do so.  Carnivores look for the most efficient way to make a kill, and will avoid fights with others a lot of the time to avoid serious injury.

Also, it wasn't mentioned that this Spino is ill or wounded, so it wouldn't make sense for a Yang pack to attack something that easily scares them.  

There was a documentary done by the Kratt Brothers where they documented a pride of lions that specialized in killing elephants.  The lions only attacked calves, and never adults, and whenever a bull elephant came around, the lions cleared out, but they said that if this bull was ill or hurt, than he would be fair game to the lions.  The same concept applies to this match-up.

except for the fact that the elephant/lion bodymass ratio is like10 to 1 and the yang/spino bdymass ratio is only 2 to 1.

Alphadino, of course the pack would have to be desperate. If they weren't, they wouldn't even think about attacking, they'd just leave. That's how about any fight to the death starts when large and not large predators battle is because the not large predator is desperate. 

i stated that they are despreate.

6 is overkill.

6 x 4.5 yields a combined mass of 27 tons. That's double the weight of what's considered an 'average' spinosaurus.

Mass plays a large role in these kind of conflicts, after all.

If they're desperate as TK stated, they won't relent on their attack..Now, if they loose one or two, i see them as acting more cautiously over anything else.

The Yangchuanosaurus pack should take this with ease

i totaly agree. its simply just to much claws and jaws coming at it. and the hatchet bites would be truly devastating and painful.and i never said this was an average sized spino....

It would come down to the health and vulnerability of the spinosaur.

I wonder if they could take this thing down. Not sure what this species of tyrannosaur is but it looks like they have gone with feathers on an albertosaurus or something. This is really pushing the bird theory...but looks cool.

https://www.youtube.com/watch?v=yYh3ix_cVCk