Phantom 25 Verado 400R set up

[Toffen Gunnufsen]

Hi!

I hope you are well

I have owned a Phantom 25 since 1998. Its a 1985 model. I have ran engines like Johnson V8 3.6 litre 300 Offshore Race, Promax 300 SVS, 2 x Merc 2.5 EFI SVS, Verado 350 Sci and now I have ordered a Verado 400R with a Sportmaster gearcase.

The Verado 350 Sci worked well on the ol lady. Top speed has been 81-82 mph spinning a REV4 25 pitch prop with a 30 mm shortened tube to 6,550 rpms. propheiht approx 1,75 inches below the bottom.

I have strenghtened the deck with divinycell, and due to the new CG I have made a 8 inch notch to the boat. It has worked out well.

The question is how high I can get the propshaft before the boat drops the bow. As we all know the P25 runs flat but high on the water. My Phantom has no pad.

Have any of you tried a Sportmaster lower unit on your Phantom 25? How high have you managed to run the propshaft? And which prop worked out best? I will try a 4Bl Turbo TXP and BBlades 4bl Blaster. The 400R gearcase needs to be run at least with the propshaft even with the bottom.

Happy New Year

Cheeers, Toffen

[TomLinley]

Toffen

I don't run a Phantom 25 but we do build the 32, which is taken from the original Phantom 31 and have rigged Verado 400R's in various configurations to find the best set up.

Currently we run a 18" in house made stand off box, with the Sports Master Nose cones around 8" higher than the bottom of the hull.

Be interesting to know how the 25 feels with the weight of the SCI on the stern.

Our own developed 32 is 3000kg, non stepped and with a full cabin forward. With twin 400's the top speed we have seen is 97.4 mph.

We have about 500 hours experience now with Mercury 400's and have developed new parts with upgrading steering and other parts. Just ask if we can be any help.

[TomLinley]

This was the lowest we ran the 400R's - the nose cones in line of the hull, however it was like driving with the handbrake on. We raised the engines 6 inches more than this and then gained considerable speed.

You also have to be careful not to run the engine too low as the exhaust port can hydraulic the engine when coming off the plane if its too close to the water line.

[Toffen Gunnufsen]

Hi!

Thanks for al this.

When I used a Promax 300 SVS I did not have a notch. Total setback was 7,5 inches then. However, the boat ran very flat and I needed chop to get it up in speed. In high seas it was very forgiving. And I very high seas I used my ballast tank. I ran the propshaft on my Tourqemaster llower unit approx 2.5 inches below the bottom. Top speed 75-76 mph spinning 6,100 rpms with a Tempest A45 25 prop.

When I swopped to twin 2.5 EFI SS engines I was toe high if the balance going to be too tail heavy. The engines was mounted directly to the transom. The heavy duty bracket as a 2 inch setback built in. The boat still ran very flat, but ran extremely well in high seas at high speed. I could easily run 80 mph in 1 meter seas. Top speed was 86-88 mph depending on conditions.

When I bought my 350 Sci I mounted it on a Stainless Marine Gorilla jackplate with 4,5 inches setback. The Verado 350 Sci has a built in setback of approx 4 inches. The balance has been great, and for the first time I managed to get the boat to fly. In high seas I need the ballasttank more often though.

The boat deck has always been very light weight and thin. That has been a problem when people suddenly walked over it. Sometimes my heart has been in my throat. So I decided to strengthen it with divinycell. I think the total extra weight is approx 20-25 kilos. I lost 2 mph at wot, and the boat was running very flat again. So this spring we made a notch in the bottom of 8 inches, and I recouped my lost 2 mph. The boat still runs good offshore as the running surface and strakes still are in full lenght at cruise speed.

I have experienced some issues with the power assisted steering of the 350 Sci. Its not precise enough. And since its a little "un-precise" I loose speed at wot. Howeever, I have been told that campered skeg on my ned 400R will help when I run the engine high counteracting the torque. I presume you run straight skegs and latham like side bar steering?

What do you mean with "the exhaust port can hydraulic the engine when coming off the plane"? I know the 4 strokes are sensitive to get the lowest cylinder filled with water if mounted too low. I use my jackplate actively running it all way up when going off plane. I will use my ballast tank as well for this season. Especially now when I have a notched transom.

What kind of props do you use on your 32 footer? Thats a nice hull by the way And a classic!

Speak soon!

Cheeers, Toffen

[TomLinley]

Toffen

Yes the Verado steering has more locks than would like, however all Mercury high performance outboards suffer from this, they like the vague attributes as standard due to the risk element of producing high performance fast engines. Remember the majority market for these engines are big sports fishers and heavy centre consoles, where the GT/Cruising style helm is perfect for that application, along with the torque tabs on the skegs etc, all go to make a fast but comfortable, easy to drive set up.

For race or performance applications some modifications to suit your driving style can be carried out. We now run a modified steering set up and different size helm to reduce the amount of turns required. Yes the torque tabs have been removed from the skegs, this gained us 4mph!

Ill drop you a PM re the steering set up and props. There is also a superb hydraulics expert in Southampton also who is very good if you require something bespoke.

[Toffen Gunnufsen]

Hi!

Thanks for all this ! Much appreciated.

I have changed my helm from a standard 40CC to a 50CC, so lock to lock is now 3,5 turns. However, i still feel the steering is not precise enough.

I have been recommended to order a SM with cambered skeg since this is a single application. Its different when you have two engines running counter rotation. I am not sure what to do here, as the cambered skeg can reduce crabbing, and by doing so increase speed. My engine is not yet delivered, but I need to act fast to get a straight skeg.. A friend of mine within the racing industry recommend the cambered skeg.

What do you think? I used a torquemaster LU on my Promax 300X, and that helped on speed.

Cheeers, Toffen

[TomLinley]

Toffen,

I will reply to your email to Spectre, we can go into a lot more modifications then stated, but you start to go into Warranty issues. I will reply via email then go into further detail.

Best
Tom