Hello My name is Dave
My 1978 ru20 Dyna campervan lutonpeak style unit, has been in the family since 1981 and gone around Oz twice with original 5r motor on petrol and was converted to dual fuel LPG 10 years ago.
The old fella who had it, my Dad never took it past 90kmh but since I got it, I removed about 500-600kg of chipboard interior replaced it with alloy tubing and light pine and have been able to overtake semis and road trains at 120km per hour on a slight gradient uphill even climbing to 140kph and still wanting to go faster but been what it is, its not recommended or safe but driving it for so many hours on end with some dirty rigs spitting up stones and debris while zig zaging halve asleep on the hwy makes you do angry things.

The 5R is an underrated motor with its 5 speed column shift manual and big diff it has very good torque once its going and fuel economy is surprisingly good for what it is, a big giant box on wheels.

ATM Its been off the road for 5 years and going start her up again with new fluids, fuel and battery soon as it has been done before without issues.

The only problem is now she hasnt been registered for 4 years and for a RWC she might need wheel cylinders cover seals or new wheel cylinders. Anyone got a link or contact for best prices for them?

Also although the 5r still runs well, after 230,000km I have thought about putting in a high compression 18R OHC motor. The problem is I dont know how I would match the 18R to the box bellhousing. The reason I was thinking of the 18R is that its also a fantastic motor and I know someone who has one rebuilt with higher compression, re-ground cam for better economy, electric dizzie, goes very well and very cheap.

Does anyone know how I can match it up to my 5 speed?

 

I am slowly building a sole lpg 5r with a subaru wrx turbo, swapping the K202 6.1:1 diff ratio that the 5r dyna and stout had for the K082 4.1:1 landcruiser centre, the turbo will be low slung using a lpg mixer set up off a v6 commodore straight six falcon, the idea is to cut running cost being on a pension without loss of power and pending boost should actually be better than an engine swap anyway. The stout toyoace and possibly your version of the dyna have the same braking system as 40 series landcruiser, so I have found re kitting my wheel cylinders extremely cheap buying the rubbers individually at a brake and clutch place under $60 for master cylinder and all slaves, which was only like $2 more than a kit to do only a wheel cylinder and all the brake shoes were under $100 at the same place

 

Brake parts online may be able to help you
Cheapest I have found so far for 76 stout they probably have dyna

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