Prowler prop dilema...
 

Ok, so I've been playing with a few props since my 525SC rebuild. HP is now around 600.

Tried a stock Maximus 24 (that's a big prop). Excellent planning, & did real well in rough water, but not much on the top end. I could only get 4700 rpm, 59mph.
Also tried a labbed Bravo 28. Trouble getting on plane, had problems with cavitation, excellent cruise speed, 4000 rpm 56, but top end was limited to 4600 rpm, 66 mph.
I came across an OSO'r selling a labbed Maximus 24, the tube was shortned, & the diameter was reduced to about 14.7, & cup was added.
He was kind enough to allow me to give it a try before commiting to buy.
Ran it yesterday...
5300 rpm 73 mph (GPS)...planning was excellent, & the added cup was a huge help with trim. According to the slip calculator, around 10%. I did however, seem to lose some mid-range. At 4000 rpm, I was 52 mph. With the labbed bravo 28, same rpm, I was 56, but it limited W.O.T...
Sooo...Is it the reduced diameter that is giving me good top end numbers, and causing the reduced mid-range?
Would adding some pitch help with the mid-range?
Obviously, I can't have diameter added, but I could just start from scratch on a new 24 Maximus, & not have the diameter reduced so much. I do like the rest of the recipe of this prop, so I guess I'm trying to figure if this prop can be adjusted to fit, or should I just buy new?...thus, my dilimea.

It comes in 15", 15,25" and 15,625" dia., so you don't have to get a 15,625" cut down. Try a 15" dia.

Alot of information and options to boot. I think we could cover more ground by talking on the phone.
If you would like, call me and we can spend some time putting all the options into perspective.

Brett

Thanks for chiming in Brett...
I've chatted with Brad about my prop search. He sent me the 24 Maximus to test. I spoke with him today, & we talked about a 24 or 25 P5x. I'm wondering if..."out of the box", I may be closer, & then let you tweak it to fit.
He said he didn't have either on the shelf, but would check to see when he could get one.
Not a real big hurry, end of the season, but I am blessed to live on the Gulf Coast, & I am able to run year round...I just may have to bundle up...:eek:. So, I can still test run props any time.

Sounds to me like the 28 was just too big. At 4000rpms with it, the sticks would have to be pushed farther and you would be using more fuel than you are with the labbed Maximus 24 at 4000rpms.

Those numbers with the labbed Maximus are pretty good.

Brad has done some looking and is now waiting for a reply. He will get back to you when he knows more.

We discussed this and the Labbed Maximus you ran was actually done by us. The top numbers are great at 9% and the speed is good. Get us the serial number and we'll know more. Yoi can't expect to get the same mid range numbers with 24 pitch compared to 28 pitch even with the extra blade. There will have to be some give and take in order to get the best of both worlds.

Brett

Thank you Brett...
I run the majority of the time in the mid-range, so if I can get a prop to work there, I'll just let the top-end be what it is. I will say, I was VERY happy with the planning, & the trim I was able to get with the labbed 24. So, I'm real curious how the P5x will compare, out of the box...
I'll wait to hear back from you guys.

**forgot the serial #...BB3577

Griff, thank you for the input...I was suprised with the performance of the labbed 24. IMO, a 5 blade is a good fit for the Prowler hull...

I played around with a prowler years ago that a good friend use to own. The boat handled best and ran good numbers with a P5X. Brett also lab finished a 26 bravo 4 blade for him that ran 73-75 with 500 efi. This boat had some setback with the ITS. He soon went blower power and ran into the 80's, blew her up and then sold the boat. Have fun playing with props, give Brett the best data you can and he will help you get where you need to be.

Morgan
Sutphenboats

If anyone else would like to try the Maximus also let me know.