# 15 Maverick HPX-T Prop Suggestions



## Smackdaddy53 (Dec 31, 2012)

Call Jack Foreman at Crossroads Propeller


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## JoshJ (Dec 7, 2016)

From what everyone is saying I will second what was said above and suggest you call Jack.

However, to help with your original question, I have an HPX T with a 60 Yamaha. It is the high trust engine which means it has the bigger lower unit like the 70 and 90. Motor is mounted on the highest hole with no jack plate. The boat came with a SCD 4 blade 14" with heavy cup. I was only getting 5200 trimmed out and 4400 trimmed all the way under.

I bought a new off the shelf SCD 4 blade in a 13" with the factory cup which was hitting the rev limiter at about 3/4 throttle. I have since had cup added to the 13" prop, but have not tested it yet. I expect it to turn around 6100 with the cup added.

The SCD does seem to run well with the HPX T. It does slip a little if you take off hard from a dead stop, but it comes no where close to blowing out. It also holds well in the turns and in rough water with no cavitation issues.

The SCD does also seem to be faster compared to the numbers I hear about on other HPX T's with 70's. I am getting 32-33 mph with the 13" prop bumping the rev limiter. I would expect to get close to 35 once I get the RPM's under control.

The SCD is a thinner blade compared to the pictures I've seen of Jacks props, so it won't last as long. Once I wear the two props out that I have I will probably be calling Jack also.


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## dcollins (May 3, 2015)

Thanks guys. Had the local marine store order the SCD 4 blade 14 pitch. Should be in over the next few days. Will report back the results.


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## Ward Theriot (Apr 19, 2017)

I know I don't have a similar boat, but I'm running an Xpress 16' Hyperlift hull with a Yamaha F70. The hull has a pad so it does need a prop with some bow lift. I am set up the a 10" setback with a Bob's hydraulic Jack plate. I have an SCD17 that I started with and it did not provide any bow lift and it did have some slipping in corners. It ran 39 MPH at 6400 RPMs. I then ran an NRS17, had run run it extremely high (prop shaft 2-1/2" below pad) to turn enough RPMs. Good grip, just too much rake for the F70. Speed was 43 MPH @ 6400 RPM. I'm trying a Mercury Spitfire X7 17P this weekend and will repost with the new numbers.


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## Ward Theriot (Apr 19, 2017)

Correction on my previous post, the SCD Prop is a 15P, not 17P.


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## dcollins (May 3, 2015)

Got the skiff out for about an hour today with the new SCD 4 blade 14 pitch. Was able to get it to turn 6200-6300 PRM WOT. Jack plate was set about 1/2"-1" from lowest setting. Never hit the rev limiter however. Not sure I ever have. 

Top speed was around 34-36 depending how much I had to use the trim tabs. Wind was blowing pretty good so didn't get much flat water to air it out. I was getting similar #'s out of the old Turbo prop. 

However, the SCD has much more stern lift which makes the boat slide more in turns if I don't use the tabs or slow down when turning. All in all, happy with the prop but will take some time to get more familiar with it and how it performs. 

Sent the Turbo out to get repaired since it was dinged up and bent a blade.


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## Ward Theriot (Apr 19, 2017)

I want d to give an update on the Mercury Spitfire X7 test from this weekend. The prop is 13" x 17P 4 blade. The prop comes with their PVS (vent plugs in hub) the holes hot was better the the plugs removed. This is the fastest prop I've ran on the Yamaha F70. It ran 45 MPH (GPS) at 6300 RPM. When I check the slip on a prop calculator, it gives a negative number. Mercury may rate their pitch numbers on the conservative side to give me these numbers. My next prop to test will be Powertech's RED3 17P. Will post once tested.


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## Smackdaddy53 (Dec 31, 2012)

45mph is scooting on a 15 foot skiff...jeeze!


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## Ward Theriot (Apr 19, 2017)

I'm running this on a 16' Xpress Hyperlift Hull(pad bottom similar to a bass boat). Once the hull gets onto the pad, the speed increases. I'm also having to run the engine high using a hydraulic Jack plate with 10" of set-back. The boat model is H16DB.


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## JoshJ (Dec 7, 2016)

Ward Theriot said:


> I'm running this on a 16' Xpress Hyperlift Hull(pad bottom similar to a bass boat). Once the hull gets onto the pad, the speed increases. I'm also having to run the engine high using a hydraulic Jack plate with 10" of set-back. The boat model is H16DB.


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Sweet boat, I've never seen any thing like it before. The SCD is not the right prop for that though. You need bow lift to make that boat talk to you.


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