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WW & Catto comparison 360

Light cub on 35's with 360. Currently have a 8636 catto and love it. It rips. No complaints. Was wanting a spare a lil more coarse/shorter i.e. 8442 or 43 for ski work and just cruising when I'm not landing in the short rough stuff. Now I'm scratching my head about the 200l 82". Seems most guys once they find a setting they like don't adjust much in th field...? I have not pulled but can tell the WW would prolly have to be set to redline on take off to beat the 8636 catto..but where would the shorter 8442/43 compare on pitch settings of the WW.? I Know guys with the 8442/3 and I know I'll like the cruise, & im sure it will still do fine on pulling outta holes just nothing like my longer/flatter catto. So.. any comparisons between a 8442/3 and a WW would be appreciated. Cattos have done me well from less engine cubs up to my 360 exp & I'm kinda partial to them. Musical props gets spendy so trying to get insight from guys with knowledge on the 2. Thank you
 
I know it's a different animal, but have heard that a 7636 on a c90 at 2300 out pulls the ground adjustable set at 2600...not apples to apples but same scenario
 
I know it's a different animal, but have heard that a 7636 on a c90 at 2300 out pulls the ground adjustable set at 2600...not apples to apples but same scenario

Better specify which WW because there are two companies. Both make a propeller to fit the o-320/o-360, both are adjustable . Biggest difference is one is 44LB and ground adjustable with a allen key, the other is ground adjustable
but it has to dismantled and re-pitched, only 18lb and max 82".

BTW a borer fixed 82" 1A200 is a good option for climb/cruise on the O-360, 35LB I do believe.
 
I did purchase a 8443 catto and it feels to perform just as well or better than a 8443 Pawnee, at a 100 rpm less. And cruises 10mph faster.. will stick with catto until more ppl run the WW
 
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Again apples and oranges, but in reference to your C90 comment - a ground adjustable 76 Sensenich spanked a 7636 Catto on my c90 cub.
The problem with comparing different brands is that blade profiles and chords are always different. It’s nearly impossible to compare numbers across brands, you have to compare what works best from each brand on your setup.



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In reguards to the c90, perhaps the 9.5 pistons I had had something to do with it...not sure it yours was stock but 7:1 to 9.5 was a substantial increase in Rpms
 
I too wish there was more talk on Catto props as I don’t like musical props as well. I have the 84x37 and would love to try a couple other props on my O320...I would love to try the 84x35 and then a 82x42...
 
I can assure you a 8436 with 10:1's will not disappoint with 320. Check your hubs! There have been several cracking. Mine being one of them
 
I can assure you a 8436 with 10:1's will not disappoint with 320. Check your hubs! There have been several cracking. Mine being one of them
Please expand what you mean by hubs? Of the prop itself? Or the crank flange? 36 over a 35, and yes I have 10:1 pistons...
 
I had a 8436 catto on my 0-320 9:1s and a 82" WW, I adjusted mine all the time for cruise or take off, takes about 10 minutes without the spinner on. I felt the 82" was a little to much prop for the 320 but never tried the 80" which is what WW recommends for 0-320s now. I now have the same 82" on a 0-360 and really like the combo, pulls hard and cruises fast. Haven't played with pitches or compared to a Catto on the 0-360 yet. Both props are great but I like the cruise and being able to adjust the WW. My only complaint of the WW is rock chips on the back of the blade that take some epoxy off and need to be fixed, but easy to do. The catto never got these

Here are the results from a pull test done on the same day on the 0-320 9:1s. Cruise numbers were at 2450 rpms
WW82" pitch 9* static 2600 572 lbs cruise low 80s Catto 8436 static 2330 560 lbs cruise 88mph
10* 2550 550 lbs
11.5* 2420 530 lbs cruise 95
12* (didn't pull test) cruised 103

Same airplane with 0-360 WW 82" at 14* cruises 107mph on 35"s

Heard Reeves in Anchorage is carrying the WW 80" and 82" props now, maybe they will allow you to demo one.
 
Perfect. So 12lbs more thrust with the WW. At almost 300 Rpms more static than the catto. Something to be said for the catto. My stock 160 with a 8437 pulled same as a 10:1 borer pitched at 41 at 2500. With the catto at 2300
 
Perfect. So 12lbs more thrust with the WW. At almost 300 Rpms more static than the catto. Something to be said for the catto. My stock 160 with a 8437 pulled same as a 10:1 borer pitched at 41 at 2500. With the catto at 2300

A longer prop with finer pitch is going to win the climb race, should also win the pull test too . That said, Catto admitted to me the other day the 84-37 does not do best in a pull test. Apparently it needs to move in order to work efficiently ,even other less capable props can pull better in a static but not win the race out of the hole or perform better in climb .

Are Catto measured in inches or is the number a pitch angle? Majority of props are measured in inches, I do believe Catto is set up on degrees which makes comparisons even more difficult. All things being equal more pitch (inches) the faster a ship can go for any given diameter as long as the engine is in the range. A friend tried a 84-37 catto on his stock O-320 could only get 2150 static , The Borer 82-43 managed 2350 static . The Catto is a little longer but the 37 if inches should have exceeded the Borer , I can only assume this is degrees .
 
I had a 8436 catto on my 0-320 9:1s and a 82" WW, I adjusted mine all the time for cruise or take off, takes about 10 minutes without the spinner on. I felt the 82" was a little to much prop for the 320 but never tried the 80" which is what WW recommends for 0-320s now. I now have the same 82" on a 0-360 and really like the combo, pulls hard and cruises fast. Haven't played with pitches or compared to a Catto on the 0-360 yet. Both props are great but I like the cruise and being able to adjust the WW. My only complaint of the WW is rock chips on the back of the blade that take some epoxy off and need to be fixed, but easy to do. The catto never got these

Here are the results from a pull test done on the same day on the 0-320 9:1s. Cruise numbers were at 2450 rpms
WW82" pitch 9* static 2600 572 lbs cruise low 80s Catto 8436 static 2330 560 lbs cruise 88mph
10* 2550 550 lbs
11.5* 2420 530 lbs cruise 95
12* (didn't pull test) cruised 103

Same airplane with 0-360 WW 82" at 14* cruises 107mph on 35"s

Heard Reeves in Anchorage is carrying the WW 80" and 82" props now, maybe they will allow you to demo one.

Both the Catto and WW here are being shown in degrees not inches so hare to compare to other manufacturers. What you clearly proove howver is that a shorter coarse pitched prop will show lower RPM and lower static pull but in flight when the prop unloads it will be most efficient and cruise faster. A longer prop with flatter pitch will pull harder in a static test and RPM will be higher, more efficient out of the hole and best climb but limited in cruise.
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Finding the best prop is a function of need , for fixed pitch you have to choose between best climb, best cruise, or a comfortable compromise . Even variable pitch propellers still have a range because you can only adjust pitch, length is fixed.

Best solution for experimental guys is two props. One long for climb, a second shorter for cruising long distance. Probably cheaper than a constant speed by a margin, lighter, and you get the best of both worlds. My situation allows a comfortable
compromise though even for my purposes I have chosen a prop that gives a slightly better climb at the expense of a little top end.
 
Plain and simple. The only person who posted solid pull test, which is the only way to tell I think, said that a WW set to damn near redline, pulled pretty much the same(12lbs more) than a catto at almost 300 rpm less. And the catto cruises faster than a WW in the extremely flat setting. Which prop is more efficient? Cut and dry to me. I ran a 8436 on a 320, awesome prop for short work. I feel it's equivalent to my 8636 on 360. Those are results I was looking for, so I thank you for the pull test. Get a catto to static 2450ish, and what would results be? Surely the little the WW beat the catto by would diminish and then some. It would be nice to have the adjustability of the WW, but it takes me like 7min to change props, to put my 8443 catto on which will still cruise with the coarse setting of the WW(touch over 100 at 2400)
 
Plain and simple. The only person who posted solid pull test, which is the only way to tell I think, said that a WW set to damn near redline, pulled pretty much the same(12lbs more) than a catto at almost 300 rpm less. And the catto cruises faster than a WW in the extremely flat setting. Which prop is more efficient? Cut and dry to me. I ran a 8436 on a 320, awesome prop for short work. I feel it's equivalent to my 8636 on 360. Those are results I was looking for, so I thank you for the pull test. Get a catto to static 2450ish, and what would results be? Surely the little the WW beat the catto by would diminish and then some. It would be nice to have the adjustability of the WW, but it takes me like 7min to change props, to put my 8443 catto on which will still cruise with the coarse setting of the WW(touch over 100 at 2400)

The Catto must be in degrees not inches . If your 8443 catto is cruising at over 100mph that is over 100% efficiency IF the prop was actually in inches. 43inches X .00095 X 2400 RPM = 98mph . At 90% efficiency the Catto would need 48 "inches" of pitch
to cruise at 100mph. The 43 rating on the Catto is obviously degrees not inches.

WW and Borer work really well for the intended purpose as does Catto . None is a clear run away winner when all the variables are equal from what I am seeing . I have a chance to try a 84 X 37 Catto myself, I will likely give this a go for sure, will break in my new engine on the Borer 82-45 first .
 
I don't understand math, and formulas and the like. I understand the gps and the scale

No one is making any definitive claims , this is all conjecture for the most part. The math I use for prop pitch is however fundamental . When using prop pitch in inches one can convert to theoretical distance or speed . If you have a catto prop that is 43 and than number represents inches then as the simple formula goes 43 (pitch in inches) X RPM ( 2400) X .00095 = speed. In your case the 84-43 would be : 43 x 2400 x .00095 = 98.04 MPH. 98 MPH is what you could get in a perfect world 100% efficiency.
If your are actually getting 105% efficiency something is off, according to the discussions I have read, that is not possible .

As I said I suspect Catto pitch numbers are degrees . It's not about a 2mph discrepancy, that can happen in any of the variables, at the end of the day it means nothing . Your AS indicator could be off, your GPS number off a tad and the pitch given may not be precise either , manufactures have different methods of measuring , apparently .

All I'd like to know is how Catto measure pitch at this point, inches or degrees and is there a way to correlate the two .
 
Sorry I'm not up to snuff bout it all. All I know is what the sticker says the prop is. What it cruises at, and that it out performs a Pawnee at a substantial less rpm
 
Sorry I'm not up to snuff bout it all. All I know is what the sticker says the prop is. What it cruises at, and that it out performs a Pawnee at a substantial less rpm
Pawnee is a different animal altogether I imagine , probably different pitch , different design , not apples to apples comparison . I have a friend with a Pawnee on a o-360 identical aircraft , my aircraft has a o-320 and a Borer .

I destroy him on takeoff by a massive margin, in cruise it is the opposite, he is 25MPH faster . That just shows the polar opposites that exist, if we had identical engines, identical prop length and identical pitch on the two different props then it would be a better comparison . Bottom line, a longer prop with fine pitch will be the best for out of the hole and climb, the Catto has proven it is more than up to task . Would be nice to know if catto is degrees or inches and have a way to convert if necessary.
 
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