1987-242SS454

Can anyone recommend a propellor for a 242 formula with a new/rebuilt 454, no bottom paint, and a 1.47 Alpha drive. In has stock outdrive exhaust. I have a 20 pitch quicksilver QA6186 20 4 blade alum. on it now, that I wiped out. It gets out of the hole nice, but I can only get 43mph gps @4500RPM. I am told the boat should do over 50mph. Can anyone recomend a stainless prop for this boat, and what specs it should be? I am hearing that a bravo 1 22 pitch seems to work well and get mid 50's GPS at around 4600 rpm which is right for an 87. The boat is suppose to weigh about 4150lbs. dry
Thank you,
Brian

prostock85

I run a 3B 21p mirage plus with the same engine pacage in a 24 and it runs 51.6 on a gps. I have a 1.5 to 1 ratio. Hope this helps

prostock85

Which ever prop you go for, be very careful with the outdrive behind a BB. I have blown a few so far.

throttleup

With 1.47 gears running a 20P prop at 4500 RPM at WOZT you have 26% slip which is very high. You should definately benefit from a new propeller. I would recommned a 3B for your application though I think the Mirage Plus will work well on your boat possibly a 19P.

Julie

1987-242SS454

The formula dealer I boat the boat from told me to start with a 3B mirage 19P. I found a few people on here though with the same boat that are running 4B Bravo I 22p labbed and getting 54.5GPS @4600RPM and one with a top speed of 56 mph @ 4800rpms. Someone is also running a 23p Mirage (non +) and turning 4500-4600 RPM and seeing 56 MPH. What would be the benefits of the 22p bravo I vs. the 19p mirage plus?

Pat McPherson

I have a friend with basically the same boat.
1987 Formula 24SS.
454Mag Alpha (330HP)
He runs 17p Mirage plus with a 1.3 something drive ratio.
The boat tops out around 50 on the GPS.

My guess is a 19p Mirage plus or 21p Mirage.

bbladesprops

The Bravo propeller will aid in the low and mid range. You seem to be chasing the big number on the top end. We have the entire Mirage Plus line for testing if you would like to try the 19 and 21. I recommend these props also.

1987-242SS454

I want to get it over 50mphGPS, but The boat is heavy and needs help out of the hole. I also have the weak Alpha drive behind the 454 so I am thinking that the 3 blade Mirage plus may be easier on the drive than the 4 blade. I am thinking of trying the 19p mirage plus first

1987-242SS454

I am still playing around with props...I have tryed a few. I tryed a 19p aluminum that gave me about 4800RPM, but only 38MPH. I tryed a 21p Aluminum that seemed to put a load on the boat and then seemed to cavitate as the boat planed out. It was kind of weird. The best so far that I tryed is a 17p Mirage from a friend, and it felt great. It was turning too many RPM's at about 5000, but hit 46mph(fastest ever) and may have gotten more but I did not want to hold it at 5000RPM. It was great out of the hole too. It did not respond that well to trim though. I need to knock off about 300-400RPM, so I think I'll have to go to a 19p mirage as most have recommended. What will the difference be between a mirage and a mirage plus for my boat? I have tryed all of the local boat guys I know to try and borrow a 19p mirage, but no one has one. The one guy I know told me there is a Mirage plus copycat prop that sells for about half of the mirage. Does anyone know of something like this or should I just spend the $ and get the name brand. Also who/where is the cheapest place to get a mirage from. Thanks for all of the help.

throttleup

The copy cat prop you were told about could be one of several. The closest thing to a Mirage is the Quicksilver Thunderbolt. The best way to describe it is; it's the same but different. It is made by Mercury and would be considered the Quicksilver version of the Mirage Plus. The bad news is that it's not half the cost of the Mirage. Ir's maybe $20 less.

There maybe some other prop out there he is talking about but you generally get what you pay for in the marine industry.

Matt