Prop people what pitch
 

We are curently building a set of big in big blocks for the 32 fountin fever we picked up. My question is what pitch prop would you guys recomend for a qiuck cruising speed, top end. Out of the hole isn't really a concen.. Any info, thoughts on this would help out.. I was something in the neighborhood of 28 pitch.. Thanks JOHN

Re: Prop people what pitch
 

Need more info;

At what rpm will the new motors make peak HP and torque?
How much HP do you estimate?
What is the gear ratio of the current drives?
What motors are currently in the boat and what is the speed/rpm/current prop and pitch?
What year is the boat?

Re: Prop people what pitch
 

More than likely we will want to work with a 4 blade prop to get the best top end and decent cruise, if those are the main concerns. As asked in the previous post, the more info you can supply, the better we can be at supplying the best advice.

Re: Prop people what pitch
 

28's are probably about the pitch used with stock power. Big power will need more depending on hp.

Re: Prop people what pitch
 

Ahh ok, figured I should have posted that info up from the get, my bad fellas. Boat is 1992 32 fever, hp estimate will be in the low to mid 600 range per motor, we bought the boat without power, but it does have a set of i beleive 27 pitch 4 blade hydromotive props, as they was a small set the previous owner let go with the boat, are too small. I can say that redline on the new motors will be no more then probably 6200, where they will make the most hp, tq not sure havn't picked cams or anything yet, but the hp and tq numbers cross at 5200, at least they have on all the dyno's i have seen, as far as gear ratio,1.5.. Hope that helped a bit.. again Thanks JOHN

Re: Prop people what pitch
 

Kinda putting the cart before the horse. Worry about props after its built and dynoed. There is no reason a "big inch big block" needs to spin 6000 rpms to make low to mid 600hp. What cubes are you going to make it???

Re: Prop people what pitch
 

shooting for probably 540's or so and prob not going to have them dyon'd, I guess what i am asking is where about pitch,should the props be for a boat this size and power, just for a guestamate, I don't have the cake to jup up, down in sizes a bunch... Thanks John

Re: Prop people what pitch
 

No problem, when the time comes, we can send out a couple different sets of test propellers and then make a educated decision. This way you won' t waste $ trying to get dialed in. Once we determine the correct casting, we can do any fine tuning you desire.

On another note, you may find turning your engines in the mid 5000 range sufficient for the hp goals you have set. Your builder should be able to help you there.

Call us if you have any questions.

Re: Prop people what pitch
 

Spend $100 bucks on shipping and use test props from throttle up or bblades.
I would probably start with some Bravo 30's or 32's

Re: Prop people what pitch
 

Ok thanks much GRIFF,THROTTLE. BBLADESPROPS I will get intouch with you here in the near future, as we don't have the engines done yet.. Again thanks guys :drink:

Re: Prop people what pitch
 

When you get the motors together and some more information on them I would suggest using the boat as a dyno. By using the same prop but in different pitches you will be able to find at what rpm the boat runs the fastest. This would then be a target rpm for WOT.

Your boat is an ideal candidate for Throttle Up CNC props. You will not find a propeller manufactured to a higher tolerance anywhere, period. We can then manufacture a CNC machined custom propeller for your boat that will perform and last behind your motors. All this for about the same price as a "lab finished" cast production propeller.

Re: Prop people what pitch
 

Be careful of using many propellers to determine the correct rpm for your engines by seeing which ones make you go the fastest. A 34 pitch may be the fastest propeller on the boat but will bring the rpm's below the range that will offer the best longevity, and can harm the engines. Talk with educated engine builders about your components and get a aproximent range to work from. Then using different propellers in that range will get you where you need to be. Fine tuning can then be achived.


I have a couple quick questions about the new TU CNC'd propellers being touted.

I saw a quote of $1300 per propeller for a 4 blade CNC. That is a long way from the "under" $900 for a custom Lab Finished 4 blade Bravo 1 propeller, that will arguably perform as well as any other propeller on the boat. That would be over a $800 difference or increase for the pair of CNC'd props! Is this correct?

Another statement I have seen is that of durability compared to a "cast" propeller. Aren't these CNC'd propellers made from a "casting" that you machine? These aren't billet. This would mean they are still castings with the same ability to have internal voids, cold rolls etc. that cause failures. Inconsistencies aren't causing failures, pouring procedures are.

No discontent intended, I just want to get the facts straight.

Re: Prop people what pitch
 

For current pricing one can call or go to our web site
http://www.throttle-up.com/specials.htm .

For additional information on our props one can go to
http://www.throttle-up.com/p4.htm .

The big advantage is we can make a prop to suit a customer needs. We can make a prop that is thicker in applications of high horsepower. Our props are made from all virgin material and heat treated for additional strength. Our casting process has yielded extremely high quality castings, since the outer surface of the casting is machined away porosity would be more likely to appear verses putting a polish job on a production cast prop.

There are other aspects of our casting/machining process that tend to result in a higher quality product but I won't go into details as we have spent a lot of money and time developing those processes.

Re: Prop people what pitch
 

OK.

These are castings. As with yours, Mercury propellers are made from virgin material only.

Labbing to a specific recipe has always been a way to build a propeller to the exact specifications for any given application without having HP levels affect durability . More HP, keep it thicker. More HP, make it thin and go faster but chance blade failures. (unlimited options that are repeatable)

The Lab Process also removes the surface polish which exposes any voids that are near the surface. There can still be internal flaws in any casting that can develop cracks with usage (stress risers). That is just the nature of any investment casting whether it is hand finished or CNC'd.

I see the pricing has gone down $200/prop as a introductory price.

Thank you for the responses.