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-   -   Looking for prop ideas. Checkmate 253, LS Power (https://www.offshoreonly.com/forums/prop-talk/361053-looking-prop-ideas-checkmate-253-ls-power.html)

corey331 06-06-2019 06:31 AM

Looking for prop ideas. Checkmate 253, LS Power
 
Looking for some prop advice on my Checkmate. I've been running the LS engine for a few seasons and am really happy with it and have it tuned in pretty well, so now it's time to start really playing with props. Right now I am running a stock 24 Bravo. The boat handles very well with that prop, but will only rev out to about to 5600 rpms. It makes peak power at 6100 rpm, so I would really like to get it up to at least 6000. At 5600, the boat runs right at 75mph GPS, so my slip numbers aren't too hateful at about 12%. The boat could use a little more bow lift in it due to dropping over 500lbs out of the stern swapping in the LS. I have talked to a couple of prop people and they say they can get me a couple hundred rpms with some lab work, which is a definite option, but I was wondering if anyone has any other suggestions on different props to try. I also looked into dropping down to a 22p Bravo. That would get my rpms up, but I wouldn't pick up any speed with the same slip numbers. My thought was to maybe treat it like an outboard, small displacement/high revs and try some of those props. Any help/ideas would be greatly appreciated, thanks!!!

Here is a video of a 74-75mph pass so you can see how it carries the bow and handles. I did cross over some boat wake in there as well.

Gimme Fuel 06-10-2019 08:22 AM

On my 1997 253 at various power levels:

I absolutely hated the handling of the Rev4 prop I tried although it was one of the fastest top speed, handling sucked. It would bow steer dangerously at speed if crossing waves/wakes even trimmed out.

I tried a Mirage+ once, could hardly get on plane without blow out, and once on plane it I looked at throttle prop would blow out and forward motion ceased.

Bravo I good all around but could never rid the porpoise unless cruising nearly 50 mph. Boat never felt like it truly flew on the pad. When I added bigger motor and the extra 1000 rpm, it lifted stern too hard and got a bit squirrely. Off it came.

I ran an old Mach Sterndriver 4-blade round-ear prop for a while. Was actually a really good all around prop. Not as good as the hydromotive, but better handling than the Bravo I.

My absolute favorite prop on that hull was the Hydromotive QIV:
-I had a labbed QIV with shortened diffuser tube and added blade cupping. This was the best recipe for boat handling an trim attitude although it was a bit too tall in pitch for me so I couldn't use it in the end. Boat was perfectly balanced on pad at 65 mph with almost zero chine walk. Really eliminated the porpoise until down to about 35 mph with zero tab.
-I tried a box-stock one and it handled like the labbed one although needed ALOT more trim, basically right up to the safe limit of a Bravo's trim range. this one ended up being correct pitch I needed, and if I had kept boat I would have had the same lab work done I mentioned to make it the perfect prop. Flew boat perfectly on the pad just like the other stock QIV.

bbladesprops 06-12-2019 11:45 AM

Identical boats will often need different props depending on the boat itself as well as the the way the owner uses it and has it set up.
It most instances, even a Lab Finished Hydromotive Q4 are the less desirable propeller compared to the Bravo 1. Simply put, the Q4 has more stern lift. In most cases a properly Labbed Bravo 1 will out perform a Labbed Q4. The Q4 can be made to be better and some folks like the solidity of the ride but others prefer the overall performance on the B1.
This is my observation over the last few decades. This is not to say each application doesn't have its own opinion and that they aren't valid. They are.
We have recipes for both props to run on Checkmates of different sizes.

Brett

corey331 06-12-2019 12:02 PM


Originally Posted by bbladesprops (Post 4691520)
Identical boats will often need different props depending on the boat itself as well as the the way the owner uses it and has it set up.
It most instances, even a Lab Finished Hydromotive Q4 are the less desirable propeller compared to the Bravo 1. Simply put, the Q4 has more stern lift. In most cases a properly Labbed Bravo 1 will out perform a Labbed Q4. The Q4 can be made to be better and some folks like the solidity of the ride but others prefer the overall performance on the B1.
This is my observation over the last few decades. This is not to say each application doesn't have its own opinion and that they aren't valid. They are.
We have recipes for both props to run on Checkmates of different sizes.

Brett


I agree on the boats acting different, even in the same model. My 253 must be some kind of anomaly because I have never had any kind of porpoising issues with it. I do love how the Bravo handles on my boat. It cruises great, is easy to get on plane and at speed is very stable. Would working my Bravo be an option to gain some rpms and bow lift?

Alwhite00 06-12-2019 02:14 PM

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bbladesprops 06-12-2019 02:42 PM


Originally Posted by corey331 (Post 4691522)
I agree on the boats acting different, even in the same model. My 253 must be some kind of anomaly because I have never had any kind of porpoising issues with it. I do love how the Bravo handles on my boat. It cruises great, is easy to get on plane and at speed is very stable. Would working my Bravo be an option to gain some rpms and bow lift?


We should be able to get you about 200-250 rpm and better bow lift with less trim.
Speed gains vary and nobody can guaranty a exact number.

Brett


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