Pro XS should have more ***Moxie***???

[gotboostedvr6]

You've turned a pad tunnel into a semi displacement hull by running too much weight. Your tunnels are buried at speed. That's the only way to still have water pressure with your setup at 60mph.

[Whaaaaat]

The pictures may be misleading my eyes. Are your pads completely level? They look angled in the pictures

[FMP]

On one video the side view at speed shows flat running with freeboard. The spray coming off both inside edges is likely hitting the lower right at the water pickups.?

[home made tunnel]

You've turned a pad tunnel into a semi displacement hull by running too much weight. Your tunnels are buried at speed. That's the only way to still have water pressure with your setup at 60mph.

The tunnel is definitely out of the water at speed. I can feel it rising up on the pads. And because under my feet is just a single sheet of 1/2” plywood, I can feel the water slapping the tunnel top at slow speed.

You can see in this video it has no problems going slow as well... speeds are probably 35mph on 1st pass, 25 on 2nd, and 20mph on 3rd pass. Watch the pads on the back of the boat. It has plenty of lift (I think). At about 30mph is where I fee the tunnel top is completely out of the water, and it feels like it’s running on waterskiis.

https://youtu.be/ZN4fBLR4Ixg

The pictures may be misleading my eyes. Are your pads completely level? They look angled in the pictures

they are slightly angled inwards by a couple degrees. I’ll have to put a straight edge on it to show- the picture is an optical illusion making it look worse.

On one video the side view at speed shows flat running with freeboard. The spray coming off both inside edges is likely hitting the lower right at the water pickups.?

yes, at speed it does run flat. The pads provide a lot of hydrodynamic mechanical lift.
And im sure the inward spray is what’s hitting the lower unit for water pressure. I’ll have to get a camera back there. Just not sure if I will before the seasons over. I don’t think an iPhone mount will work haha.

[FrenchPhil]

60+mph kudos anyways. Thats at 5% slip, so a 26 cleaver could give you 69mph if you can keep the rpm at 6100. I wouldn't put the engine any higher before you tried a few more cleavers.

[FMP]

Limit is 6300
This looks good, or the five blade version
http://www.ptprop.com/index.php?page...id=46&vmcchk=1

[blacktruck]

Water looks pretty rough in those videos, couldn't get a good read on how it was riding. In general, I would say, as you're finding out, reduce drag as much as possible. Get your gearcase as high as possible. I didn't see what prop you were running? The only thing is, the reverse angle on your sponsons, cause you to run deeper, drag a bit more.

Checkout the little F4S 60 HP boats, and how they ride. They go about 75 MPH. Obviously a little lighter than yours. But, your engine is great, will make an efficient hull really move for sure.

[home made tunnel]

They really don’t angle in. (Looking from back) it’s a funny optical illusion. Here’s a broom stick on the bottom to show. Broomstick is the best thing I had laying around at the house.
The vertical transom face that the drain plugs are in are angled slightly forward. (Center part more aft, outboard part more forward) if that makes sense?

Those racing boats are pretty sweet! I’m sure they corner much better than mine. I gotta take turns slow. Mines more built for sloppy choppy water, which it handles quite well in my opinion. Better than I expected though.

The bare hull was 500lbs. I'm sure with steering, battery, tank and gas, seat, and all other various rigging, the hull is probably 650lbs+. But it's solid

I think I'm on the right track... with a lot of help from this forum for sure. Including the folks who think it's a displacement hull, and a fat heavy four stroker lol. And too much motor for the boat (crazy to think that someone on this forum would say that!). But Nay-sayers just fuel my desire to make it work.

I think if I can get it to 70mph, i'll be very happy with it. Reliability of a new fuel injected motor, fuel efficient hull, able to handle some choppy water eloquently, and have all the weirdo's at the gas station look at me funny with a big motor on a little boat haha.

NEXT STEPS: Flip around the jack plate from 5" setback, to 2.5" setback (COMPLETELY FORGOT this jackplate had that option)!!! I also may flip it to a negative 6* wedge type. It has that ability too. So at slow speed, I can have more trim down to control low-speed porpoise. Who would have thought I'd fix high-speed porpoise, but now have a low-speed issue?!!??
Keep watering and fertilizing my cajones to get this thing up to speed and be comfortable.
Keep trying other props.... like a 4 blade
Get a camera to view the transom and what's going on with the motor - and how it's 2 to 3 inches above the pad and still getting 20psi water pressure...
Raise the motor a bit more

[home made tunnel]

Water looks pretty rough in those videos, couldn't get a good read on how it was riding. In general, I would say, as you're finding out, reduce drag as much as possible. Get your gearcase as high as possible. I didn't see what prop you were running? The only thing is, the reverse angle on your sponsons, cause you to run deeper, drag a bit more.

Checkout the little F4S 60 HP boats, and how they ride. They go about 75 MPH. Obviously a little lighter than yours. But, your engine is great, will make an efficient hull really move for sure.

It's a mercury through-hub cleaver. 48-77094a4 23p
Hard to find any details on it anywhere online, but they're a dime a dozen on Ebay.

[FMP]

So called the proptech guys, http://www.ptprop.com/index.php?page...id=46&vmcchk=1
Will run way high surface if needed.
The scd4 not too high , it'll blow out but will out run the cff4 if buried. The cff4 is a 14 smaller blades , the scd4 a 13. The cff4 won't blow out surface running.
They'll exchange props for $50 within 30 days, good if you live in the area. Anyone know these props?