High Speed Stalwart

[Richard Coutts-Smith]

That would be Stalwart of course.
Surprise vist to Corowa 2011 was one of the very few Stalwarts to be privatley imported.
Even more surprising was the owners aim, to use it as a mobile home for a round Australia trip. The Main differential system has been apgraded (New ratios) to give a a cruising speed of 65MPH, capable of 70mph easily. For the doubters out there, the Stalart was driven the 350(?) kms, Geelong to Corowa at 65, as its maiden run. Unfortunatley rhe LPG system froze solid, so most of the run was done on the way too small reserve petrol tank.
The Axle wind up that is associatted with this style of vehicle has been alleviated by the use of disconnect/reconnect back drive shafts. This, in effect, gives selectable 4x6, 6x6 congiguration.
This is a Mark I swimmer, but has not been swum since being imported.
Next job is a solid roofed poptop and fit out.
Of course, a real man would SWIM it around Australia......
I was more than impressed to see and hear one of these in the flesh.
Rich

[Ron King]

The Stolly at Corowa was a MK 1.
I have a MK 2 with crane (limber) at Nowra NSW and another one of the same model is just north of Brisbane Qld.
I have heard another 3 stollys may be imported .
I hope to drive mine one day to Albury from Nowra and swim it down the Murray river.
This will be a few years off.
Ron

[Richard Farrant]

Hi Richard,

I also had a quick chat with the owner at Corowa. After he told me of the 65mph on the road, I think he must have dispensed with the No-Spin diff fitted to Stalwarts and gone for a conventional type as in the Saracen. Reason I think this is that driving a Stalwart at 30 mph, they tend to lurch one way then the other due to the No-Spin diff action, so holding it on the road at 65 would be a nightmare. Would love to have tried it for comparison.

A good variation of British vehicles at Corowa, and a few surprise ones appearing at the last minute, the Stalwart included.

[Ron King]

The owner of that Stalwart said some thing of interest to me.
The high speeds wouldnt be possible without the drive disconnects as this reduces the drag for advailible power.
I personally found steering the Stalwart is not a issuse if you know what to expect and the disconnects would help greatly with this.
The gearing increase was of 40% increase on the transfercase reduction gears.
Being a MK 1 and a bit lighter help the performance of that stalwart.
That gearing increase I have calulated reduces 1st gear to about 66 to 1 and 5th gear to 8 to 1 .
I found a stalwart off road with standard 103 to 1 gearing 1st gear is still a bit too tall.
66 to 1 would very greatly reduce off road performance or the ability to climb a steep river bank to get out of the water.
For on road work it is perfect.
The Stalwart very badly needs a 2 speed transfercase and due to the Stalwarts unusual drive train it is impossible to do.
The drive disconnects is a straight forward job to do.

[Richard Farrant]

Originally Posted by Ron King

The high speeds wouldnt be possible without the drive disconnects as this reduces the drag for advailible power.
I personally found steering the Stalwart is not a issuse if you know what to expect and the disconnects would help greatly with this.

Hi Ron,

I can see it is quite possible the no-spin diff causes less problems if not driving on all wheels, all the Stawarts I have worked on were of course permanent 6x6.

Something that has just come to me is that the Salamander airfield crash tender was faster in top gear, 10.05 ratio, against 12.9 in a Mk1 Stolly, and this was running at approx the same overall weight, and they both have the same 1st gear ratios.

I have spent much time standing on my head working inside them

regards, Richard

[Ron King]

Originally Posted by Richard Farrant

Hi Ron,

I can see it is quite possible the no-spin diff causes less problems if not driving on all wheels, all the Stawarts I have worked on were of course permanent 6x6.

Something that has just come to me is that the Salamander airfield crash tender was faster in top gear, 10.05 ratio, against 12.9 in a Mk1 Stolly, and this was running at approx the same overall weight, and they both have the same 1st gear ratios.

I have spent much time standing on my head working inside them

regards, Richard

Hi Richard.
Due to Australias distances I am looking for gear ratio options on the stalwart.
A 80 kph/50 mph maximum speed with a 60kph/40 mph cruising speed at say 2700 rpm would be fantastic without changing the first gear crawler ratio for off road work.
I know the Saracens used by the Australian army topped out at 72 kph with the preselector gearbox and different bevelbox ratios.(tyre size too)
I have no idea if the Salamander used a manual or preselector gearbox and ratios.
Only three salamanders made it to australia and they most likely dont exist now.
I was thinking if fittting Sarasen components could give a wider spread of ratios on a Stalwart gearbox.
Do you have any idea of what Salamander/Sarasen bevel box/hub reduction/ preselector box ratios are .

Ron

[Richard Farrant]

Originally Posted by Ron King

I know the Saracens used by the Australian army topped out at 72 kph with the preselector gearbox and different bevelbox ratios.(tyre size too)
I have no idea if the Salamander used a manual or preselector gearbox and ratios.

I was thinking if fittting Sarasen components could give a wider spread of ratios on a Stalwart gearbox.
Do you have any idea of what Salamander/Sarasen bevel box/hub reduction/ preselector box ratios are .

Hi Ron,

The Salamander had a preselect gearbox and fluid flywheel, as the Saracen and Saladin, and this set up could make driving of a Stalwart on long road trips, better. I do not have much info on the Salamander, but can give you Saracen and Saladin ratios. I guess you have the manuals on the Stalwart and will already know them?

Saracen
ratio of a separate bevel box 1.77:1
hub reduction 4.125:1
pre-selector g/box ratios;
1st 10.27:1
2nd 4.73:1
3rd 2.64:1
4th 1.61:1
5th 1.00:1

overal ratios engine to wheels;
1st 103.2:1
2nd 47.5:1
3rd 26.60:1
4th 16.20:1
5th 10.05:1 (this gave a Saracen on 11.00 tyres, a top speed of 43 mph or 69.2 kph)

If you need any more info let me know.

regards Richard

[Richard Coutts-Smith]

Hi Ron,
Can I be in the front of the queue when you bring it down??
They are an awseome bit of machinery.
Rich.

[Ron King]

One day I may need help to fuel it.
It is a rich mans toy and I am only a humble motor mechanic.
My stolly is on historic plates and drivable, but I have much to do to get it to a standard I am happy with and reliable, let alone swimming it.
Treating rust and painting is a huge job on this sort of vehicle.
Its off road performance and especially suspension is good so far.
I have not had the vehicle long so I am still learning.
The preselect gearbox has a lower first gear ratio and is the reason why the saracen etc can run a higher transfercase ratio.(ie more top speed)
The preselect box cannot be used with the stalwart because of the need the drive the water jets from the top of the box.
The alvis manual gearbox used has a crawler ratio of 8 to 1 which I believe is limited of being a lower ratio by the need of the gearbox to be flat and compact.( ie a bigger gear will not fit )
The only other options for a wider spread of gear ratios is the transfercase, which is a very special item too and can not be replaced with another type.
I think a two speed transfercase ,may be possible at great cost by reworking the standard design and fabricating various new gears and housing etc ......far ,far beyond my means.
ideal tranfercase reduction of 2 to 1 for road use and 4 to 1 for off road.
The stolly is somewhere in the middle.
Thanks for the information Richard.