Let me start off stating this is my first non-jetboat so I really have no idea about props. I have a 93 27 fever with a carbed 502 it is stock except for the intake manifold is a team G. I currently am turning a mirage plus 23 right hand 3 blade prop to 5500rpm. Is this a good prop for this boat?

My -93 with 525SC came with a 14,5 X 24 Mach 4 blade.
3 blade are normally faster.
If your tach is correct, 5500rpm is a tad to high for a stock 502. What is your GPS speed?

66mph GPS

Fountain use to run a lefty prop on that boat,you could use more pitch..seems your a jet boat guy so heres some info,if you want less rpm's then you go up in pitch in the prop you will loose 100 rpm's for every 1 '' more pitch you put into the prop..if you go from a 3 blade to a 4 blade you drop 1'' of pitch so if you wanted to try a 4 blade prop you would need a 22 pitch prop..

downside to going to a bigger prop is it will take more time to get the boat on plane unless you have mucho hp..

Good number for the package. 18% slip according to BAM slip calculator:
http://www.go-fast.com/Prop_Slip_Calculator.htm

If you like the handling with your current 3 blade, try a 25.

I just got the boat so I am getting familiar with everything. I did notice the boat rocked side to side at WOT runs. I would love to see 70mph and slow the motor down a little. Also don't want to give up much on hole shot if possible. I want everything

Going from a jet boat to a Fountain is a huge step trust me I know, I did the same thing a few years back. You are not going to want to hole shot that boat like your jet, you will break drives. Drop the tabs and tuck the drive and slowly roll into your throttle and it will plane just fine. I know from experience that the 27ft Fountain likes a left hand prop much better than a right hand prop. I would borrow a 22 pitch LR Bravo and try it out before you do anything else. That is a good place to start with your set up.

Yea, I know better than to holeshot the boat. It seems to get on plane decent with about 3/4 throttle and not tabs. I would like to try a 4blade lefty, but I thought I should use something like a 24pitch to slow the motor down to around 5100?

I just re-read my post and you are correct, I put 22 when I meant 24.