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...high flow oil pumps...Not sure if any were made for the triples.
HIGH CAPACITY OIL PUMP
for fitting to all variations of the BSA/Triumph 3 cylinder engine...both the feed and scavenge pumping gears lengthened by 50%. Therefore the possible pumping capacity is increased by 50%. It should be noted that the pump will not in itself provide increased oil pressure, as this is controlled by the oil pressure relief valve...
High capacity triple oil pump assy.
Part number: 71-1351A Price: £385.00
This is a good article:
Oil Pumps
...the Triple oil pump, what can be done to improve it, and how to identify bad pattern pumps from possibly good original pumps...all original pumps have a date on the body. This dating comprises a month and year code, e.g. 10-72 for October 1972...Two basic styles of pump were used in original production, and are interchangeable in service...later T160 models were fitted with the large bore oil feed from oil tank to pump, and the matching hole in the back plate of the pump was larger to suit...it is mainly internal clearances that affect the efficiency of the pump...feed gears with an end clearance of .0008" to .0012", and scavenge gears with an end clearance of .0012" to .0018",
Read full article here:
And
this is an interesting technical article about engine heat from Vintage Bike Magazine (some highlights pasted below):
Engines and Heat
INTAKE HEATING
Let’s begin with the intake stroke, assuming that our engine of interest is operating at or near peak torque...This heating of the intake charge both helps and hinders...Turbulence promotes heat transfer.
HEAT AND DETONATION
There is a second reason why this gain in intake temperature is harmful to engine performance...
REVERSE COOLING
This raises another point...Cooling air passes through the exhaust-side fins and in doing so becomes hot. Then it flows on, to the intake side of the cylinder head, and this hot cooling air heats, rather than cools, the intake side of the head...
EXHAUST VALVE TEMPERATURE
As the intake air enters the combustion chamber, it encounters the glowing, red-hot exhaust valve. This heats the intake charge even more...In larger engines, the valves finally had to be internally cooled by partially filling a head-and-stem cavity with sodium. At operating temperature, the sodium became liquid and, sloshing back and forth between head and stem, carried excess heat out of the valve head, to the cooler stem. There, it could be conducted away into the valve guide. This in itself was a problem, because it caused oil in the guide clearance to coke, then seize the valve in the guide. During the early 1950s, Norton had to run a small exhaust-valve cooling radiator on its Manx racers, and BSA had to use a new, high-tech gas turbine alloy (Nimonic-80) in the exhaust valves of its Gold Star engines to prevent valve cupping from high-temperature creep...
COMBUSTION SPEED AND POWER
For these reasons, performance is better in engines with shorter combustion periods...If you can build an engine that needs less ignition timing for best torque, it will in general make more power and run cooler than combinations that require longer timing...the cylinder head runs much hotter than does the cylinder...
DETONATION AND TEMPERATURE
When an engine detonates – even slightly – its temperature begins to rise...(but) when an engine begins to detonate, its exhaust gas temperature (EGT) falls...
COMPRESSION AND EGT
...The higher compression is raised, the cooler the exhaust valve and exhaust pipe will run...Harley tuner Don Tilley commented recently that at 11.5 compression, almost the entire header pipe of his Buell Harley engine became red-hot on the dyno. When he raised compression to over 13, only the first six inches of the pipe became red-hot...
HEAT FLOW TO THE EXHAUST PORT
...about half of the heat that flows into an engine’s cylinder head is picked up from the exhaust port...
REDUCING EXHAUST PORT SIZE
...engineers such as Jim Feuling have shown repeatedly that most engines do not need exhaust ports and valves as large as they have in stock form. Smaller ports of higher angle and more streamlined section flow just as well or better than stock size, and their smaller surface area further cools off high head temperatures...
PISTON COOLING
In air-cooled engines, piston-to-wall clearances should be as small as possible, so that piston heat can easily pass into the cooler wall...The less surface area of piston exposed to combustion heat, the cooler the piston will run, and that means, if at all possible to use the closest thing to a perfectly flat-topped piston...
COATINGS?...
by Kevin Cameron
Read the full article here:
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