What props do I need? 1990 27.2 Formula SR-1?????!!!
 

Hey,

I have a 1990 formula 27.2 SR-1 with twin 454's - bravo drives. I'm pretty sure there not mags. They have approx 20 hours on motors new rebuilds and boat has 482 total. Have a tubular platform with straight threw hull exhaust. I have tried 19s 3 blade. Was 5100 rpm at 55mph. Boat came with them. Traded for 25 pitch 3 blade mirage. 64 mph on gps with 4 ppl in boat and 1/4 tank. 3950-4000 rmp. Traded them in for 23 3 blade to get more rpm. Tried them and got 60mph with 400$ in fuel in tank and 5 ppl in boat. 4300-4400rpm. I saw a guy with same boat as me and he says he has 24 4 blades at 68mph. I know this boat is 66-69 mph all day. I have no idea what props I need here??? Anyone have any idea what will work for me. ?? Whole reason I bought this boat was because of the 454s for extra speed and it's not there right now. Help!!!!!!

You will not see 68 MPH out of a 272 with 330's. 61-63 MPH is more like it with the correct props. What are the 3 bladed props you're running? Mirage Plus are the best 3 blades for that hull, note Mirage Plus not the standard Mirage. I'm running hydromotive on my 292 sr-1 and I like them a lot. Last year when I had 330's in the boat I would typically be around 62-63 mph. If you go the hydromotive route use the 24 pitch props, I was right at 4600 rpms wto.

He's right every 272/454/330 is a 62 mph boat maybe in the "perfect world maybe 65