Help needed with prop specs
 

I have a pair 21P Quicksilver props on my Cigarette Bullet and I am looking for an upgrade. The part number on one of the props is 48-13702-A40 21p. I googled the part number but found different specs listed in various places on line. Is there a way to decipher the part number to get the specs on the prop such as diameter? Thanks

Those may be the Mirage (not PLUS) props.
Stainless Quicksilver 48-13702-A40 21P (14 3/4” dia. and 21" pitch).
Some cup was added to the prop when they made it a Plus in the 1990s.
Should be rubber hub also.
Going to Plus will drop your RPMs nearly 200 at WOT.
You can have your props re-worked to "Plus" specs.

Thanks for the information. I think I may need to step up to a Mirage 23 prop. My boat will sail right past 5200rpms with the current 21’s. I am thinking about going with the Mirage 23 non plus PN 48-13705 A41 23P. Would that be the same diameter as my current 21’s?

I believe so.
You should loose around 200 rpm per inch of pitch so a 400 rpm drop at WOT.
Your straight bottom boat really should like the added bow lift of the Mirage Plus. If you used the same 21" pitch, I'm guessing you would see around a 200 rpm drop from the added cup although the boat having less drag at high speed may let the engines rev that 200 rpm back to the same rpm while adding a couple of MPH.

Do you have access to a prop shop/marina/dealer that will allow you to "try before you buy"? Do you know where you want to run on the top end? Are you willing to sacrifice any 'hole-shot'? Generally speaking, when you pitch up in prop size you'll find it affects how you come out of the hole. SFOcean is spot-on with the suggestion to go to a Mirage Plus in the same 21" pitch...try that first if you can get the props. I'd also suggest a Revolution 4 in the same 21" pitch. You go to 23" pitch and you may not like the way the boat acts on the bottom end.

I appreciate all of the info. The boat has a lot of hole shot currently with the 21’s. We live on Lake of the Ozarks and we were running with some guys at the shootout poker run a few weeks and I opened it up at about 40mph and when I looked at the tachs they were at 5500 so we’ll past where I wanted them to be.

How much power are making ?

You also might want to try a 4 blade on that hull. If you are on the Ozarks, Call Cool Breeze Prop shop, he has demo props.
Cool Breeze 573-348-0555.

I would guestimate around 400hp. It has the original 365 horse 454 Mags that are rebuilt and I added more aggressive hydraulic roller cams with roller valvetrain, IMCO thumper exhaust and better intake and carbs.

Thanks for advice, I will give them a call.

I have the same props, Hale Prop trimmed the diameter to 20.1 and added cup to them, it's a night and day difference, everywhere from jumping on plane to midrange, can still get 5200 out of them. I have less horsepower than you so trimming diameter might not be needed in your case.
Prop slip is down in the single digits (which people say is impossible)

20.1 Diameter on what drive? :D
You sure you didn't mean pitch?

FACEPALM!!! Insert embarrassed face here