Hi,

I have ordered a 400R to my ol Phantom 25. The engine will be delivered with a Sportmaster gearcase with cambered skeg. With the 350 Sci and 5,44 HD gearcase the highest I could run it was propshaft approx 1.75 - 1,5 inches below the bottom before the prop lost bite (cuppped REV4 25 with cut down tube). Top speed 81,3-81,7 mph at 6,550 rpms. I have in total 13 inches setback (new notch 8 inches + jackplate 5 inches). Plus the built in setback of the Verado..

People tells me that the 5,44 HD gearcase hits the wall around 82 mph, plus if you run it higher than 2 inches below the bottom it tend to lift the transom. In conclusion, its made for running more submerged and less speed.

I expect my boat to run approx 85-87 mph if I am lucky. So I should be within the speed the Sportmaster gearcase require. The only issue that concerns me is the propshaft height.

Do anyone know what its the lowest propshaft height the HD Sportmaster gearcase should be run? I do not think the REV4 can be run much higher. A Bravo does not carry the bow enough. Maybe a Max5 or a Turbo TXP would be the trick.

Cheeers and thanks! Toffen

a lead, maybe some one this thread could help,

http://www.offshoreonly.com/forums/s...bs-thread.html

cough,

We need an Outboard section in Technical

We ran our fastest 28' Eliminator Speedster at 2" (plus a lil) above the running surface. Everything great, just had to watch the trim; a "fat trim" would set off a buzzer (water pressure).

These motors need PLENTY of water ... !! We'll try to post some pix later ...

Thanks! Much appreciated. So a positive trim will steal waterpressure. Its going to be a exciting journey this!

Hi!

I have done 65 hours on my 400R Phantom 25 combo. Best speed is 86 mph at 7,040 rpms with a reworked REV4 25 prop. Two persons and 1/4 tank of fuel. Engine height 0,75 inches above the bottom. It surprises me how much positive lift sportmaster gearcase gives. I run neutral at wot, but if I jack the engine higher I loose speed. Lower propheight the same. I gained 4 mph rising the propshaft 0,5 inches .....

So I need to find a prop that can be run higher and still hold bow up. I think bigger diameter prop is the ticket. The engine is strong, I only need to free up the hull more and get the gearcase out of the water

Two props have caught my eye; Merc Max5 and the new design to BBlades 4-Speed OB/FX. What do you think?

Great fun this!

Thanks.

Cheeers, Toffen

I would also consider the Bravo FS. It has a shorter exhaust tube, which will help with minimizing the stern lift already gained from the gearcase. The cup height is also reduced when compared to a std Bravo. Keep in mind Bravos do not run true to pitch, so a 24 is actually a 23.3, a 25 is actually a 24.3 etc.....
The diameter of the Bravo FS is also larger at 15.25, so this will be much better for higher X dimensions.
http://www.mercuryracing.com/boat-pr...rd/bravo-i-fs/

Toffen

I have run some lower pitch Max 5's on my 308 as back up beater props when in unfamiliar water or carrying significant weight. They have a great hole shot and good midrange compared to my Dewald cleavers but give up top speed to the Dewald's.

I also have some BBlade Bravo's that were nice in the 308 when I ran the 300XS's

Both props were great on my cat and provided good bow lift.

Hi,

Got my boat on the water today

The prop worked well. Managed 86,3 mph out of the box with the propshaft 1 inches above. I have a notch of 8 inches pluss jackplate 4,5 inches. So in real world is approx even with the bottom as the water hits higher with notch and jack.

I will go 0,5 inch higher and see. Slip is very very low. 6,5 % on a non stepped V hull. I need to get the rpms up 150 rpm to get 100% out of the engine, so I will try to raise it. The slip may well go up, but getting it to 7,000 rpms will give me more horsepower.

Cruise speed was good as well. 50,5 mph at 4,000 rpms and 64 mph at 5,000 rpms. With the REV4 25 pitch I managed 48 mph at 4,000 rpms and 61-62 mph at 5,000 rpms.

Hopefully with a little tweak we can get it to 87 mph and I am very happy.

Cheeers, Toffen

Hey again,

Good news, new record. Better conditions today with 3ms wind. We managed two runs of 88,6-88,8 mph - but in the end we managed a whopping 89,0 mph at 7,060 rpms. This translates to approx 7% slip. Its still the MAX5 25 pitch prop. Propshaft height 2 inches above the bottom.

So if we sum up, we managed during the years:

Johnson 3.6 GT V8 300 = 76 mph - Raker 25 prop
Promax 300 SVS = 75-76 mph - A45 Tempest 25 prop
2 x Merc 2.5 EFI SS SVS Brucato = 86-87 mph (87 mph only once) - Mirage 25 lab & Hydromotive 4 bl 25 lab
Verado 350 SCI = 80,3-81,3 mph (80,3 with new heavier strengthened foredeck) - Rev4 25 lab 4 bl prop
Verado 400R = 85-86 mph - Rev4 25 lab 4 bl prop
Verado 400R = 89 mph - Max5 25 lab 5 bl prop

We will try some more runs next week. Maybe we can reach the 90 mph mark ...

Cheeers, Toffen