Right, after a quick search, these are the figures that have been the most common:
Oblivion and Nemesis: 52" max (and that's literally just about). There are 'big boy' seats which can accomodate larger sizes as far as I'm aware, although I think this may mean the 52" seats. They easily fit a person with a 49" chest.
Air: 50" (But large legs means that a rider will not be able to fit)
TH13TEEN: Can easily fit a person with a 49" chest
Rita: A person with a 49" chest couldn't fit.
Submission: A struggle to get a 49" person to fit but it still worked albeit with a bit of pain (much like the ride for smaller people anyway).
Spinball: Now, there are different stories about this. Some say that pretty much anyone can fit but a person with a 49" chest couldn't get the lap bar down enough. It may depend on waist size.
Ripsaw: A person with a 49" chest couldn't fit.
The Smiler: Unfortunately, I have no idea about restrictions on this. Someone here may know.
Other rides: All other rides should be fine for anyway as a person with a 49" chest was reported to easily fit in.
So, if you go: Probably best not to try Rita, Air, and Ripsaw. Nemesis and Oblivion will be fine as long as you use the big boy seats (Row 4 for all trains on Nemesis and you need to ask on Oblivion as only certain shuttles have these). TH13TEEN will be fine. Spinball is questionable. All other rides *should* be fine.
*All information from a user on ATA who has a chest size of 49". Results may differ.
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