Best way to settle this dispute is Armour Core vs Gundam!!!! the video game but i could see how both sides would have an advantage over another so in my opinion i think the Gundams would have a slight advantage over AC's but then again it all depends on the pilot.

armored core
http://www.youtube.com/watch?v=Rkxvubw_SW4

gundam
http://www.youtube.com/watch?v=VuTx6Lw6o_I

pwnd

I havent played a gundam game, but i am a fan of the AC series.
It took a while for me to get to be a fairly decent AC player, but i think you can customize an AC better than a gundam. So if the ac pilot knows what he is against he can fully prepare for it, like Energy damage or slug, jammers, shielding to absorb more of either energy damage or slug. you can modify the weight so you can me untouchable or be a tank that can fire an army of missiles at once.
But of course it falls down to pilots, the greatest pilot could probably take an amature with nothing but a blade. Then again only having a blade would make him extremely agile.

i dunno ....it could but then again it couldn't....

Death scythe or Heavy arms could take them out

Not sure about Death Scythe, but Nineball Seraph and White Glint seem like a good match-up.

Death Scythe is amazing, Talgeese III or Espeon or Wing Zero or really anyone from Gundam 00 would be more than a match up.

I don't know much about armor core but it was super hard to hit F-91 in Gundam Battle Universe when it used its SP take a look!:

1:45-2:05

http://www.youtube.com/watch?v=5ikEGGyHW7Y

It's not lagging, the unit seriously moves with blinding speed & can get behind or in front of you before can react Image

In the same video one of the gundams has a nuclear warhead

2:07-2:19 demolishing the entire city and enemy forces in one shot, don't wanna get caught in that!

If we're talking game-play wise, AC has gundams handily beat. If we put them into Anime-verse...well we've never seen an AC in anime have we? In anime, gundams regularly fly, shoot tons of beams, missiles, and what-have-you, and take anywhere from a few slashes/shot through the limbs to die, to surviving nuclear explosions (end of SEED comes to mind). Gundam 00 in particular can teleport in its trans-AM mode. Should we shift an AC unit, say Nineball Seraph to the anime-verse, whose to say the bastard won't have near infinite missiles (*cough*M.E.T.E.O.R*cough*), crazy dodging courtesy of frame-rate changes, 99.99% accurate blade swings that always hit just the right spot, and laser blasts that destroy enemy suits in one shot?

unless a basis for comparison (AKA level ground) is brought to bear, to put it bluntly, there is no comparison.

as long as the armored core wasnt facing one of the nuclear powered gundams and the gundams pilot wasnt a newtype then it might have a chance

It depends on the pilot. Even the strongest mechs can be defeated by a weaker mech.

I'm a pretty big gundam fanboy so I'm going to have to say no. :P

The best gundam would probably wipe the floor with the best of the armored core machines.

:| looks like with the disparity between people who know gundam and people who know AC, majority will prefer gundam because they've never heard of/played AC - and everyone has their biases. moot topic...?

gundam is more mobile than AC, so AC can't take it down!!!!!

I am a big AC fan and Gundam. To be honest it was the AC games that brought my interest to Gundam. Has anyone played AC For Answer. It is probably the best AC game to date and the powers of the ACs are totally outrageous and awesome. The Answerer or something like that I forget what it's called but look it up on YouTube and there are a ton of videos of people giving advice on how to beat this monolith. It may look easy but if you played the game without looking at the video you would have to try about thirty something times to beat it.

Anyways like some have already stated it would depend on whose standards you were going by. If Gundams were going by the rules of the AC games. Then it would be even because AC tries to be realistic with everything. Weapons have weight, a certain strength, armor, and ammo. Also some of the Gundams may not work in AC rules because of being overweight or under weight. Thus they would not have enough mobility or armor. If we went by Gundam rules and some of the ACs were granted infinite energy for flight and energy based weapons, an unlimited array of bullets and missiles it would also be a tie. Also some of the ACs would be given a slight advantage since there wouldn't really be a concern with weight issues. I like both of the series. I love Gundam as an Anime and Armored Core as a Mech game. Now Armored Core will never make an Anime because all of the Gundam fanboys will down it and compare it to the already successful franchise and I haven't played a Gundam game yet that has compared to shear detail of owning and customizing a mech like Armored Core. Now there are a lot of Awesome Gundam games out there my favorite being Dynasty Warriors Gundam 2 which I have yet to unlock every single mission in and my brother and I play the hell out of. Now if Armored Core had a multiplayer story mode or mission mode I would say it's the best mech game out there but it doesn't. You only can fight against each other which is still pretty cool.

Anyway I would agree with Tmoo. Fanboys will pick their favorite and think of no other possibility. I am a fanboy of both so I think this post needed more unbiased individuals giving more thought to it but thank you everyone for putting your opinions.