phantom 21 inboard

[bor]

hello,

I am new here but have found a lot of info about p21.
I have bought a p 21 hull here in holland ather selling my warrior 20 whit 2.5 efi and want a fast inboard.
so I found a "new"hull what was living together whit a few horses in the grass,but never rigged.
unfortunaly I think it s a se edition (can't find a id ) and afther I take a ook of the stringers there are not really good laminated stringers so have take out all the wood and fiberglass on the insite and make a new start.

I have bought a corvette engine very and gonna build this to a marine version and attach this to a bravo 1X drive ratio 1:50

Now I am looking for the best setup on the drive height and the best place of the fuel tank .

so if any one have some info or idears I am all ears !!

thank you

Armand

 

[Tony Davis]

I can see why I've never bought a Phantom, they aren't built very well are they?

 

[Jon Fuller]

First things first.

That transom looks very thin in the pics, a standard one would have been between 2.5 and 3 inches thick. For a Bravo instalation, you'll need the overall thickness to be 2 inches (52mm) for the transom assembly to go in correctly.

That setup will be pretty stern heavy for it's narrow (5 feet chine beam) design, so I think I would be inclined to have my fuel tank quite a way forward.

The motor will also want to stick out of the deck quite a bit and going high with the drive height will of course worsen this, mebbe a IMCO shortie lower unit would help this, if you can locate one.

Don't forget also that this motor being high, will make for a very top heavy centre of gravity!

The P21 is an outboard boat really.

 

[Jon Fuller]

I can see why I've never bought a Phantom

That's a lie Davis!

1986???

But yes, Steve appears to taken his eye off the ball with this one eh.

Looks like it was 'taken' without splitting hull & deck, nice flange!

 

[bor]

First things first.

That transom looks very thin in the pics, a standard one would have been between 2.5 and 3 inches thick. For a Bravo instalation, you'll need the overall thickness to be 2 inches (52mm) for the transom assembly to go in correctly.

That setup will be pretty stern heavy for it's narrow (5 feet chine beam) design, so I think I would be inclined to have my fuel tank quite a way forward.

The motor will also want to stick out of the deck quite a bit and going high with the drive height will of course worsen this, mebbe a IMCO shortie drive lower unit would help this, if you can locate one.

Don't forget also that this motor being high, will make for a very top heavy centre of gravity!

The P21 is an outboard boat really.

youre right the transom had 18mm wood and the fiberglass outside is about 9mm thick but all the wood is out the hull know and I will put everthing new in it would be 52mm when I am done

about the weight that s why I take the corvette engine ,its a all allumunium engine and weight about 180kg complete whit all acc.put the bravo 1 whit and it s about 250kg total drive train and the most of it is in the boat and not after the boat mostly whit a bracket.

about the high engine you could be right ,this week I can pick it up so can do some research on the highed ,the option for a shorty was also in my mind but have to do a lot of investments at this time so if it s not nesaserry I let that wait a little wile

thx armand

 

[Jon Fuller]

The alloy V8 will be nice!

how much power does this 'Vette' engine produce? was it easy to find? and........was it expensive?

Also, can you tell if the boat was laminated using Woven cloth, or just Chopped Strand Mat?

 

[bor]

I can see why I've never bought a Phantom, they aren't built very well are they?

I know for sure that a real/legal p21 is better build,
but the price was very good so can make some time and money toget it beter than legal!

 

[bor]

The alloy V8 will be nice!

how much power does this 'Vette' engine produce? was it easy to find? and........was it expensive?

standard 400hp and 400ft of torque
I had some luck found one for $3000k new but most asking arround 6-9k

I have a adress the sell the same engine who produce 367hp and 376tq
for $3500 but that s in australia

 

[Jon Fuller]

so can make some time and money toget it beter than legal!

Steady now!

Also, can you tell if the boat was laminated using Woven cloth, or just Chopped Strand Mat?

This may be your deciding factor in your 'sweeping statement' above.

 

[bor]

Steady now!



This may be your deciding factor in your 'sweeping statement' above.

hee jon,

just kidding about better than legal but I make it the best I can,but so far as I can see the is it chopped strand mat .

I am planning to do the stringers first whit a thin chopped and then whit a woven mat so they will getting strong.

also was thinking of core cell stringers and floor but d ont have the tools and knowledge about vacuum so forget that option

 

[Jon Fuller]

The original would have stringers of Douglas fir, one peice. From transom to forefoot.

If your main laminate is only chopped strand, I think I'd be inclined to overdo the internal structures to help the cause as much as possible, especially with that motor going in it.

Good luck, let us know how you get on.

 

[bor]

The original would have stringers of Douglas fir, one peice. From transom to forefoot.

If your main laminate is only chopped strand, I think I'd be inclined to overdo the internal structures to help the cause as much as possible, especially with that motor going in it.

Good luck, let us know how you get on.

I want to put new stringers in and begin whit smal overlay and every new lay wider and the last one over the total beam of the inside and also want to use some woven mat only beginning whit thin chopped so the curves are good laminated.

the engine I will put a dta ecm on and do some little changes on cam, springs and the intake so it will be close to 500hp (crank)
and then take a look how it will do ,I want to reach 80mph on the speedo.

hope it will work whit this set up ,the second option is to put a supercharger on

 

[bor]

The original would have stringers of Douglas fir, one peice. From transom to forefoot.

mine doesn t had real stringers they put a floor on the second step of the floor and the put "the stringer" on this whit some screw s non stainles and then on top of this stringer to the side of the hull a stroke 18mm multi plex and then laminated it from one side to the other whit 4mm chopped mat

so all the wood was sucking water on the bottom side ,this was a very bad builder!!

the hull is very solid and I think about 7-8mm thick so I am putting in new desent stringers and floor then he will hold up this power and speed!

 

[Captain Chaos]

so do we get to know where it came from? i.e whom the supplier is?

 

[bor]

so do we get to know where it came from? i.e whom the supplier is?

if I know I would tell you but still d ont know who build this one and had some other people take a look at it but no one know how s ****ed up this one !

when I have news I let you know here

 

[Jon Fuller]

wow! all that heavy ply!

How do you intend doing the hull / deck join? it appears to have some of the vertical flange missing, where the deck normally fits over the hull.

 

[bor]

wow! all that heavy ply!

How do you intend doing the hull / deck join? it appears to have some of the vertical flange missing, where the deck normally fits over the hull.

Yep, youre right he WAS very heavy I want to use a little thinner ply and laminated on both sides so it never can suck water.

they have made a litlle flair on the hull and put the deck whit the flair on it whit epoxy and laminated it in the inside whit chopped mat we never saw it this way I ll attach a photo look at the red circle

 

[Matt]

That transom looks about the right thickness for a rowing boat - or might just handle a 2hp food mixer.

 

[Wacky Racer]

Fooking hell, wish you the best of luck, hope the deck don't come off at 80

 

[bigboy]

I would just fibreglass the top to the bottom from the inside.

You could also do it like Bernico does. Without a rubrail and glass it also from the outside. Looks very nice and is strong