With higher engine power, oil cooling and lubrication must also be adapted. To ensure that hot oil is flowing as quickly as possible and to maintain optimum lubrication at all engine speeds, a larger capacity oil pump is required than the original model.
Larger capacity oil pumps have longer gears, which translates into a higher flow rate. Similarly, a standard engine can be fitted with a large capacity oil pump without any problem, which has only advantages anyway.
However, it is necessary to fit an oil pressure increase kit (see options tab), as the higher pressure no longer allows the oil pressure to be set correctly. An oil pressure increase kit (with stronger springs) ensures that this is compensated for to avoid cooling problems later on, as better cooling is one of the main advantages of a high power pump.
On type 1 engines it is sometimes necessary to bend the engine shroud slightly near the crankshaft pulley. As the oil pump protrudes further into the crankcase, it can hit the engine plate, so check that the crankshaft pulley does not hit the shrouds. You will also encounter this problem with a type 3 engine. With this type of engine you cannot even use a cast iron pump, only an aluminium pump is possible.
When choosing an oil pump, it is important to know which camshaft is mounted. In an original situation you can base your choice on the year of manufacture, but if a faster camshaft is fitted or if the camshaft has been replaced at some point, you need to pay attention to the fitted camshaft. If the camshaft is mounted to the gear with three bolts or three rivets, you are dealing with an older type of camshaft, so you should also use an older type of oil pump. All of the fast camshafts in our range are also based on the old type of oil pump. If your camshaft gear is mounted with 4 rivets or bolts, you are dealing with a young type of camshaft, so you also need a young type of oil pump.
High Power Cast Iron Oil Pump
The choice of cast iron as a material has created a very strong oil pump that will continue to do its job under all conditions. This means that internal wear will not occur quickly, which is more often the case with the original model (aluminum) oil pump.
Cast iron has a different coefficient of expansion than aluminium, and as the crankcase is largely made of aluminium, this can be considered a minor drawback.
A high performance engine obviously has a faster camshaft, which is why an older type of oil pump is used. You can choose between a standard oil pump or a Melling oil pump. Melling is not the cheapest but the highest quality oil pump you can fit, this does not mean that other oil pumps are inferior, all cast iron oil pumps are high quality. The difference between a Melling pump and other oil pumps is like the difference between a Volkswagen Golf and a Volkswagen Phaeton, both cars are superior but the Phaeton belongs to the higher segment. In every way, a Melling pump is the superlative, from finish to life span.
If you want an oil pump from the top segment, then the Melling oil pump is your choice. All cast iron oil pumps are equipped with 30 mm gears, which means a higher pump efficiency of up to 38%. All oil pumps come with a flat oil pump cover to save as much space as possible and four longer threaded ends to replace the existing threaded ends to fit the thicker housing. The gasket between the cover and the oil pump (also sold separately) is also included. The Melling pump also comes with the gasket between the housing and the oil pump, with standard oil pumps you have to buy this gasket in addition.
Aluminium high power oil pump
As you read at the beginning of this text, a high power oil pump is in all situations better than the original. These aluminum high power pumps are ideal for engines where the appearance should not be compromised. Once mounted, you can't see that a high power oil pump is mounted, so you only have advantages and no disadvantages. Compared to the cast iron oil pumps mentioned above, these aluminum oil pumps have an added advantage, the oil pump expands more evenly with the crankcase as the crankcase is also mostly aluminum, there will be little leakage, which will theoretically be possible faster with a cast iron pump.
The extra capacity of the pump is, for older years, much less than the cast iron oil pumps above, but still 25% more than the original (26 mm gears). For younger constructions (the camshaft is mounted with four rivets or bolts on the gear), the output with its 30 mm gears is the same as the cast iron models. For standard and lightly tuned engines, these high power aluminium oil pumps are a perfect choice. Supplied without oil pump cover and nuts, order these together with an oil pressure increase kit. Gaskets are included for the cover and oil pump (also available separately).
Note: The oil pump drive shaft must not be preloaded in relation to the camshaft drive, there must be about 1 mm axial play. When the crankcase is disassembled in two pieces, it is easy to check when the camshaft is in its bearings. With a rebuilt engine, you will have to measure it.
Additional note: All oil pumps are intended for Volkswagen models with a manual gearbox
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