Well, I let my brother drive my new to me boat and like a doorknob he runs it into gravel and took two decent size chips out of the prop... How bad will this affect performance? It's a 1996 Force 75 hp outboard. Right now it's topping out at about 32-33 mph and I don't know the rpm. Is it better to just buy a new prop and forget it? If so, what would a cheaper prop run me? What pitch should I get? 

 

I am a complete newby when it comes to boat motors.

Welcome to boat ownership.  You're going to have to take the prop in and either get it repaired or have them look up what prop you need and what pitch.  No idea what size boat your pushing with that 75hp and when you take it in I'd get a new tac so you know what rpm's you're running as well.

It's a 16ft fiberglass MonArk. Thank you, I'll take it in and see what the shop says. 

Post pictures of the damage to the prop.  The pitch of the prop should be on it.  You should be able to find a new aluminum prop for under $150.

Stainless steel is the top of the line for props but if you have doorknob relatives around, then you'll be better off with aluminum because of the cheaper price tag, repairs, and replacement.

I run a 2002 Merc 75 on a Lowe bass boat. My prop of choice is aluminum because I run on the Chesapeake Bay and the possibility of hitting something in its shallow tidal water is high. My choice of prop is a Turning Point Hustler prop.  They only cost about $100 for the prop and then you will need to purchase the correct hub kit for about $50. Right now West Marine has these props for sale for starting at about  $70.00.  Look at your prop for its pitch  it may say 17p. 19p etc and it should have a part number on the outer body of the prop, If not perhaps you may have to remove the nut holding the prop on and the number may be on the inner surface there.  Do an internet search with the part number and you can find the prop size and pitch.  This can then be matched to your new prop. Mine is a 13 inch diameter -19 pitch prop. The other option is to have a local prop shop repair it.  This can be fairly cheap too.