[Evenflow28123]

Hello, I have a 2012 cub cadet rzt50 model 17yi2acp056. Id like to make the mower faster. I just did a complete deck rebuild on it. Changed all of the spindles and pulleys along with the deck belt. I replaced the Transmission belt as well. When I was putting the deck back on I screwed the threads up on the deck lift hangar. So I ordered a new one of them. I did not replace the pto pulley or the drive pulley. I am going clean the carb when I get the hangar in as it was a long day redoing all the pulleys and such on the deck. I removed the screws already that control the forward limit of the handles that didn't do much. The hydro trans was whining a bit so I put some more 20w50 oil in there. I do not want to buy new hydros so if I can do any upgrades without doing new trans id appreciate it
So my questions are;
What can I do to increase speed?
What can I do to increase rpm so blades spin faster and don't bog down?
Thank you
Evan