Reusable Oil Filters - Can Going Green Improve Your Racing Program?
Saving the earth is nice, but we take a look to see if PurePower's reusable oil filters can also help you save a buck or finish better on the racetrack
From the June, 2011 issue of Circle Track
By Jeff Huneycutt
Photography by Jeff Huneycutt
This is no ordinary oil filter....
This is no ordinary oil filter. This PurePower oil filter for Chevy small-blocks features a billet aluminum construction and a stainless steel filter screen for excellent filtering capabilities.
We can all probably agree that saving the earth is a good thing. Of course, giving up showers if you live in Alabama, or biking to work in January if you live in Maine probably aren't the best ideas. And does the stuff like switching off the light when you are going to be out of the room for 15 minutes really make that much of a difference anyway?
But what if there was a way to help the environment while improving your racing program? A company called PurePower may have a product that can do exactly that. PurePower is new to racing, but it has been producing a reusable oil filter for years that's popular among municipalities, the military, and companies running large trucking fleets. And now it has filters designed to work well with small-block Ford and Chevrolet engines.
We recently had the opportunity to lay our hands on some of the PurePower filters, and they look like serious pieces of engineering. The main body of the filter is constructed completely from billet aluminum, and the filter media is a high-grade stainless steel mesh. The design works on the same concepts as a standard oil filter, except the mesh is supposed to do a better job filtering out smaller particles. It also flows a higher volume of oil and can be cleaned and reused virtually an unlimited number of times. Oh, and it's all made in the USA; that's always a plus in our book.
The stainless steel screen is folded accordion-style into a cylinder and looks, at first glance, a lot like standard paper or cellulose filter media. But by using wire mesh, PurePower says it's able to limit the hole size to 22 microns while also allowing a high rate of flow. In fact, the filter is rated at 20 gallons per minute.
Here’s a look at the filter...
Here’s a look at the filter assembly broken down into its components. In the foreground is the bypass valve. It’s equipped with a 16-pound spring to ensure that the only time the filter goes into bypass mode the conditions will definitely be extreme. The filter media is cleanable and reusable. Simply blow or wash the screen, pushing any particles that may be trapped in it back out the way they came. Then blow it dry and reinstall it on your race car. Here’s our dyno cell setup for our testing, thanks to The NASCAR Technical Institute’s hospitality. The dyno mule is a previous-generation Dodge Cup motor that has been slightly detuned but still pumps out 700-plus horsepower. In the background you can see the dry-sump oiling system with the baseline oil filter (black) still attached.
A high rate of flow might not seem like a big deal at first, but for racers it really is. Whenever any filter can't process all the oil being sent to it, it opens a bypass valve and routes the oil around the filter media. The bypass valve is there to keep excess oil pressure from damaging the filter, but it also means that whenever the valve is actuated dirty oil is being recirculated to your engine. The most likely times for this to happen are when the engine is first started and the oil is still cold and when the engine is pegged on the redline (going down the straights) and the oil pressure is the highest. Either way, it's not a good thing.
However, because the PurePower filter flows at such a high rate, its bypass valve engages much later than a standard filter, which is a good thing.
The smaller 22-micron openings should also do a better job cleaning the oil. PurePower's Rob Aquilina showed us project studies where truck fleets had increased the oil change intervals by as much as three times. The improved ability of the PurePower filter had kept the oil from deteriorating, allowing the increased run time. As a racer, you probably won't go extra races without changing your oil, but it could be quite nice in your tow vehicle, and it's always comforting to know that you're getting maximum protection from your filter.
Another advantage of the wire screen filter is the fact that it—unlike standard oil filters—is reusable. You can clean the filter screen any number of ways. Aquilina says some use a blast of air from the shop air compressor, others use cleaning solvent, while some use water with a bit of dish soap. The key, he says is to push any debris back out the way it came. In other words, pour your cleaner through the filter from the inside out. And as long as there is no damage—from wrecks or on-track contact—to the filter housing, the screen can be cleaned as often and as many times as you like.
Here’s a look at the filter...
Here’s a look at the filter assembly broken down into its components. In the foreground is the bypass valve. It’s equipped with a 16-pound spring to ensure that the only time the filter goes into bypass mode the conditions will definitely be extreme. The filter media is cleanable and reusable. Simply blow or wash the screen, pushing any particles that may be trapped in it back out the way they came. Then blow it dry and reinstall it on your race car.
Here’s our dyno cell setup...
Here’s our dyno cell setup for our testing, thanks to The NASCAR Technical Institute’s hospitality. The dyno mule is a previous-generation Dodge Cup motor that has been slightly detuned but still pumps out 700-plus horsepower. In the background you can see the dry-sump oiling system with the baseline oil filter (black) still attached.
After baselining the engine...
After baselining the engine with the original filter, the PurePower unit was swapped in with no other changes and the engine was back up and running in a matter of minutes. It took us longer to get the oil and water temps to match up to previous tests than it did to make the filter change.
Here, the oil pump is being...
Here, the oil pump is being spun up manually to make sure the oil filter is properly filled with oil and any air is properly purged from the system.
And that brings us to what we think may be the most interesting factor when it comes to using PurePower's filters in racing: The ability to quickly clean and reuse the filter media also makes this style of filter easy to break down for inspection. One of the best ways to diagnose engine problems is to inspect what (if any) materials are being shed off the engine components and are being picked up by the oil. Copper-colored debris, for example, usually means bearing problems. Aluminum can be parts of the piston flaking off from detonation. Steel can mean a whole world of things, and none of them are good.
That's why engine builders usually have an Oberg-style filter as part of their engine dyno setup. Obergs are easy to check, clean, and return to service, but they aren't generally available on wet-sump engines. If you want to check a filter, you normally had to cut the steel canister apart and pull out the filter material. This, of course, is a messy task, as well as time consuming so it isn't normally done at the racetrack.
But the PurePower filter allows racers and crew chiefs to unscrew the canister housing and remove the filter media without actually removing the entire filter assembly from the car. It can be removed, checked, cleaned, and reinstalled on the car in a matter of minutes with minimal mess. This is where we think that smart racers can take the greatest advantage of the PurePower filters.
Remember, there a many different...
Remember, there a many different ways to improve your racing operation. PurePower also makes filters for almost all diesel engines. If one of these filters can save you money on your tow rig by tripling the amount of time between oil changes, eliminating the cost of purchasing replaceable oil filters, and, according to some tests, even improving fuel mileage, that money can, in turn, be invested into your race car.
We also wanted to see how this new filter actually performed in action, so we travelled to the campus of the Universal Technical Institute in Mooresville, North Carolina—or "NASCAR Tech" as it's commonly known. There are several branches of UTI, but the Mooresville location offers a concentration of classes specifically for stock car racing. It is also constantly testing new components and different processes in order to give its students a real-world understanding for how top-level racing works. So UTI was more than happy to test the new filter on one of its dyno engines.
The engine was a previous-generation Dodge Cup engine capable of 700-plus horsepower and 8,000 rpm. We first ran a baseline with a standard oil filter with several dyno pulls, then switched out the filter for one of PurePower's units. The oil was Mobil 1 Synthetic 15-50 for all the pulls. Afterward, we put the original filter back on to make sure we could duplicate our baseline numbers.
Overall, we couldn't find much in the way of a horsepower gain. We did see a slight drop in oil pressure levels which should mean that the oil pump doesn't have to work as hard to push the oil through the filter. Still, the dry-sump engine configuration may have made testing a little more complicated. We'd like to follow up with more tests at a future date on a wet-sump engine configuration.
Overall, however, even if the PurePower filter doesn't provide a horsepower advantage, there are definitely other pluses that can benefit race teams. Granted, the filter is approximately 20 times more expensive than a standard throw-away filter but that could pay for itself in a season or two of trashed filters. Plus the extra cleaning provided by the smaller openings in the stainless screen filter not only traps particulates but also breaks any air bubbles into smaller particles, reducing aeration. And finally, the ability to quickly check your filter any time the engine seems to be a bit down on power or behaving strangely is definitely a no-brainer.
On the Dyno
As we stated in the text of this article, we performed several dyno pulls comparing the PurePower filter to a standard oil filter but didn't see conclusive proof that the filter made horsepower. Still, we thought we'd show you a comparison of two pulls where the oil and coolant temps were the closest so that you can draw your own conclusions. Still, if the PurePower can help a race team save money while also improving its ability to monitor the engine's health, we think it's probably a good investment.
|Standard Oil Filter|
|PurePower Oil Filter|