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S&S Cam Support plate and oil pump or Fueling's?

Both Fueling and S&S have an improved cam support plate and an improved oil pump in their range. The Fueling plate and pump are red, and the S&S parts are blue. The color will not affect the parts, but what is actually different. Both brands have made these parts for both Twin Cam models and the latest M8 models.

What exactly does such a "Cam support plate" do. First, the camshafts or camshaft in the M8 are mounted in the plate . In the first type of Twin Cam models the camshafts were in roller bearings, and after 2007 this was replaced by a plain bearing system. Actually the plain bearing system is just a hole in the plate with an oil hole that ensures that the camshaft in the plate runs on an oil film. The advantage of a slide bearing is that the force on the camshaft can be much higher, the disadvantage is if there is no oil pressure then you are done .....

The second thing that is mounted in the Cam Support plate are the chain tensioners. The M8 has only 1 camshaft, so only 1 chain and 1 chain tensioner. There is nothing wrong with the M8 chain tensioner, so both with Fueling and S&S it simply goes back when you change the cam support plate. This is different for the Twin Cam models, so twin cam is 2 camshafts, 2 chains and 2 tensioners. The 1999-2006 series had mechanical tensioners, the 2007 and later hydraulic ones. The mechanical tensioners are not known for their long life and in the event of failure this will cause considerable consequential damage.

At Fueling there are three options for the 1999-2006, you choose a plate for the original mechanical tensioners, or you choose a plate with an upgrade to the newer hydraulic tensioners. Finally, you can also choose a plate for camshafts that are gear driven, and these have no tensioners at all. For the 1999-2006 models, a gear-driven camshaft train is a nice option, but for the 2007 and later models, crankshaft runout makes mounting gears quite risky.

S&S also makes a cam support plate for all Twin cams and M8 models. With the Twin Cam plates, this must be done in combination with an S&S oil pump. For the 1999 to 2006 Twin Cam models there is no plate with mechanical tensioners, but hydraulics must be mounted which is of course much better than the mechanical ones. For the 2007 and later and the M8 models you can reuse the old ones. The 1999 to 2006 are also with bearings, and the later models are the plain bearing system. A big difference is that S&S uses a brass bushing on the camshaft slide bearing for the plain bearing models. This has a big advantage, if something goes wrong you can replace it.

Third, there are a lot of oil channels in the cam support plate. Both Fueling and S&S claim that the oil passages flow better than the original Harley plate and as a result, the temperature of the oil drops and the engine delivers more power. We just have to accept this. The inflow and outflow channels to the oil pump, the supply to the crankshaft, the big end, the supply to the oil filter, and the supply to the tappets and behind that the nozzles under the pistons, which provide extra piston cooling. The oil that is pressed into the tappets goes up through the push rods and ends up in the rocker arms, which in turn cool the valve springs through a small hole. There is also a channel for the oil sensor and the newer models have additional oil cooling with a channel along the hot exhaust valves. A striking difference between the Cam Support Plate from Fueling and S&S is that where the crankshaft comes through the plate, and where it gets its oil, Fueling is also just an anodized hole, without a brass bush. At S&S, yes. This hole tends to wear out, because the harley crankshafts are no longer very cleanly built. If the hole wears out or is damaged, it can affect the oil pressure. 

Another important part of the cam support plate is the relieve valve. This is a spring-loaded plunger that opens at a certain pressure. The oil pump sits on the crankshaft, and because the crankshaft has 2 flat sides on the side journal, over which the pump slides, the pump will rotate when the crankshaft turns. When the valve relief reaches a certain pressure, it moves and the oil returns directly to the crankcase. In this way the pressure remains constant, provided the oil pump has sufficient capacity to maintain this pressure. Of course, the wear of parts has an influence on this. If the space is somewhat larger somewhere, oil will drain more easily, and the pressure will drop with a pump with little over capacity. Fueling contains a spring with a fixed value. S&S, on the other hand, has an adjustable relief valve with which you can easily increase or decrease the oil pressure. 

Finally, the oil pump is of course also screwed onto the support plate. Fueling has a separate one for the Twin Cams for the 1999-2006 models Twin Cam and the 2007-2016, and of course a pump for the M8 models. The rotors are somewhat larger and thicker and a big difference with the standard Twin Cam pumps is that the pump is no longer mounted against the cam support plate with spring tension. Both S&S and Fueling promise more pressure, less temperature and less chance of sumping resulting in oil from your crankcase vent, which eventually comes out of your air filter. I believe it directly from both. But I still want to take a look at the difference between the pumps. 

The S&S pump has 3 rotors and is therefore unique. 1 for the supply and 2 for the return. S&S therefore understands how important it is that the engine does not fill up with oil. The oil slows down the crankshaft and causes the engine to run hotter. But if there are 2 return rotors instead of 1, and these are separated from each other, you will think that the total volume of the pump must be smaller somewhere. By providing the last return gear with a 2/3 deep surface, the entire oil pump falls just a little further over the crankshaft and S&S smuggles a piece of pump volume so nicely.  

The S&S pump also has a coarse filter and a magnet. It is not on the Fueling. This seems like a simple small difference but is so important when iron shavings come off a part. Unfortunately, the oil filter is on the supply side, so with iron the return part of a pump is cut acutely and you can throw it away. A simple sieve and a magnet can therefore make the difference between throwing away and reusing. 

My conclusion is simple, the prices are the same but the S&S combination has a few big advantages compared to Fueling or other competitors:  

1) a double return pump 

2) bushes in the Cam Support plate that are easy to replace in case of damage

3) the oil pressure can be adjusted by a simple bolt

4) a strainer for the pump

5) 2 strong magnets for the Twin Cam and 1 for the M8 pump from S&S 

6) there is a seal on the back of the S&S pump that provides more peace of mind at the oil pump by closing the crankshaft bearing.  

Am I S&S minded? Yes, and it didn't just happen...


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