Is a bigger throttle body better?
There is a simple answer and a long answer to this question. The short answer is yes, but you have other mods needed to match up with that bigger throttle body. For instance, if you put a 102mm TB on a stock 90mm intake you have to make sure the throttle body will open and not hit. The other thing is you put a bigger opening over a smaller hole defeating the purpose of the bigger throttle body. The openings need to match to gain the best performance out of it. This goes for your intake track as well. A bigger throttle body can only suck so much air if restricted by your cold air intake.
Other things that affect if the bigger throttle body will truly make more power are ported heads, cam selection along with exhaust setup. Exhaust for instance 1 3/4 headers vs 2" headers. No reason to really port head etc if the exhaust opening on headers is only 1 3/4 and the heads are ported to 2" for example. Again you are creating a choking point for the engine.
We attached another article that goes into this as well.