GU 98 dual fuel

[Anaurath]

Hi threedogs,

good point about the lead effects on wearing down the valve surface and even another parts of the engine (supposedly all internal parts of the combustion chamber). Obviously there is no justification on using lead due to its healthy consequences, but might be worth then to use some kind of substitute... especially because my engine is going to be soon 340.000,...

I bought this GU second hand. I paid 8 grands so, not bad at all, especially when is said that this TB45 are very tough. The rest of the car is pretty well it needs some after market replacement, but for sure in the same way that a new car... and at this moment I have a lot of fun with the project itself.

Thanks for your replies.

Yes and yes to both questions the 120 lt tank fills to about 100lt, and heads wear out around the valves because of the gas,no lead in the gas to soften valve surface

[Bob]

I went to Melb this Weekend and filled up with Gas at Calder Raceway and it took 112 Litres to fill the Gas Tank from empty. Usually it only takes105 Litres.
I did not worry about the extra Gas as I still had 50 K's to go before I parked it.
I just recently put a Reconditioned Head on (290,000 K';s). This Head had the Inlet Ports enlarged which allows better breathing and has made a big difference in the Power.
I always run a Tank of Petrol through to every 4 tanks of Gas. Also my Patrol starts on Petrol and switches to Gas automatically after a short warm up.
Been tempted to put on a Larger Exhaust System but the Truck is only used once or twice a month for Camping and Fishing trips.
Should outlast me Ha Ha

[Anaurath]

Hi Bob,

there is a very interesting point in your comment but I suppose it should be placed in a completely new thread... this thing related to the Inlet Ports in your new Reconditioned Head.

I heard some time ago that one of the best ways to increase notoriously the power of an engine is to improve both, the air intake and the exhaust.

In my mind was always the image of changing the ducts for intake, with a new air box and maybe a snorkel, and also the extractors...

After reading your threads I realised that all this improvements would work better if in addition the ports for the intake but also the ones for exhaust are enlarged...

Nice point...

I went to Melb this Weekend and filled up with Gas at Calder Raceway and it took 112 Litres to fill the Gas Tank from empty. Usually it only takes105 Litres.
I did not worry about the extra Gas as I still had 50 K's to go before I parked it.
I just recently put a Reconditioned Head on (290,000 K';s). This Head had the Inlet Ports enlarged which allows better breathing and has made a big difference in the Power.
I always run a Tank of Petrol through to every 4 tanks of Gas. Also my Patrol starts on Petrol and switches to Gas automatically after a short warm up.
Been tempted to put on a Larger Exhaust System but the Truck is only used once or twice a month for Camping and Fishing trips.
Should outlast me Ha Ha

[Bob]

Hi Bob,

there is a very interesting point in your comment but I suppose it should be placed in a completely new thread... this thing related to the Inlet Ports in your new Reconditioned Head.

I heard some time ago that one of the best ways to increase notoriously the power of an engine is to improve both, the air intake and the exhaust.

In my mind was always the image of changing the ducts for intake, with a new air box and maybe a snorkel, and also the extractors...

After reading your threads I realised that all this improvements would work better if in addition the ports for the intake but also the ones for exhaust are enlarged...

Nice point...

Here are the Specs of the Reconditioned Head.

Set up to our Turbo and High Torque LPG spec's.
We start with a good secondhand cylinder head , then ,
Hardness test , Pressure test , Crack test , Strip , Chemically clean acid dip ,
K/Line valve guides , Serdi 3 way cut seats ,
Serdi flycut combustion chamber to unmask valves , Serdi throat ports ( also known as pocket port )
Second hand Valves , Valve springs , Retainers , Collets and spring seats are hot tank acid dipped
Valve are buffed , Valve stems linished , Kwikway reface valves , Kwikway tip valves
Comec machined with Diamond tip , final cleaned for assemble , valve spring pressure checked ,
Assembled with new valve stem seals


This was done by a Company in Victoria. PM me if you want the Name of that Company