what prop do I need?

[junkyardwarrior]

I have a '87 Tidecraft Spitfire V15 (16' length) bass boat with an '87 Mariner 90 3 cylinder outboard. I currently have two props-one is a Quicksilver 12 3/4" 21" pitch stainless 3 blade, the other is a Solas Amita 4 aluminum 4 blade 19" pitch. I use it mostly for fishing...not competitively but for fun.

The QS prop I have has a really sorry hole shot. Once it's on plane, it does ok. I know that it's not optimal though. I did drill 3/8" vent holes behind the blades and that helped, but the overal condition of the prop is pretty sorry (dinged edges, etc).

The Solas prop works good but the 19" pitch isn't enough. Full throttle with the Solas, I back it off when it gets to 5700 RPM. 5250 is the max full throttle RPM on this engine. It will work well with 2 or even 3 people in the boat but with only me, it's too conservative. I like the smoothness though, and ease of planeing.

Speed with the QS prop is 52-55 mph at 5200 depending on water conditions. With the Solas, it's 48-52 but at higher RPM.

Do you all have any suggestions on a prop? I am thinking about keeping the Solas for the stumpy lake (if I knock a blade off, big deal...they're cheap), but I am in the market for a GOOD 3 blade stainless prop that will give me a good bit of bow lift. I plan on installing a 6" setback manual jack plate in the future, I do not have one as of right now, though the motor is mounted ALL the way up.

 

[steelespike]

Re: what prop do I need?

My aftermarket manual indicates 5,000-5,500 for the 87 90hp.
your ss prop results are a little suspect due to its condition but
a ss 20" prop should give a better hole shot and about 5,400.
Hustler makes an al prop that delivers close to ss performance at about 1/2 the price.When changing props there is allways some mystery as to results
when changing brands and materials this adds more variables.
When running suspect waters some believe a ss prop holds up better
for soft contacts.You might consider having the ss repaired and an inch of pitch removed. It may be cost effective.
I would suggest you get the jackplate before making any changes.