Oil filter for track car - Page 2

givory · 10-07-2015, 06:08 PM

I haven't got the pictures of my Canton near disaster handy right now. I put the big spin-on filter into a 2L vintage race 914/6 with a Carrera pump. The filter collapsed inward within minutes bypassing all the oil.
Years ago I put a Fram in. That one blew the seal out during a race. The filter is remotely mounted in the front trunk, dumping oil under the front tires. That wasn't much fun.
So there's two I wouldn't touch again.
But I've used the K&N for 10 years without a hint of problem.
Gavin

stownsen914 · 10-10-2015, 10:03 AM

I'm paying more attention to oil filters now after losing a 911 race motor earlier this year with 65 hours on it. I just parked my other car after starting to see increasing amounts of metal flakes in the "inspection" filter on the scavenge side of the oil system. Not taking a chance this time ...

I've always used Canton filters, and as far as I know have had good luck with them, though some of the stories I've read lately have me rethinking ... One of the horror stories involved one of Canton's shorter filters, which I suspect just didn't have the flow necessary. vdub, who posted above, has the same filter I use (the taller size), and it clearly just exploded on him.

So what are the other options for oil filters? I am restoring a vintage racecar and deciding what filter to use on it. To summarize the options:
1. Cannister type filter, either using the engine mounted 993 console, a remote 964 console, or a generic remote filter mount - If you use a good filter like Mahle or K&N, they seem to be up to the task, but I can't quite get comfortable with the bypass (basically when cold and possibly under hard track use, the filter is in bypass mode).
2. System1 cannister replacement or remote filters - seems to be well regarded and have good flow capacity, but their finest filter seems to be 30 micron. Is this fine enough?
3. Petersen remote oil filter - another good name, but their finest filter seems to be 60 micron.
4. Canton - not hard to fine negative reports on this filter

Any other options, or comments?

Thanks in advance.

Scott

winders · 10-10-2015, 10:54 AM

All the race motors I see built by the guy that built my race motor seem to use Mahle filters. The guy that built my race motor is sharp and well respected. I will be sticking with Mahle filters....

Walt Fricke · 10-26-2015, 09:24 PM

I have a Canton filter on the scavenge side before the front oil coolers, a System 1 filter between the cooers and the front oil tank, and another System 1 filter replacing the engine oil cooler. I've never gotten debris from engine blow ups back into the engine - the final filter has always been clean of debris.

I did find that the Canton filter would explode when the engine blew up and the debris load was excessive, similar to one of the photos. I replumbed it so the oil came in the side port, and out through the middle. This seems to work better, though a large burst of debris will crimp the filter across from the inlet hole. It still has kept most of the stuff out of the coolers, and the pre-tank filter seldom has anything in it either.

On another note, I like my engine filters vertical and facing down. Not only does this mean I don't make a mess when I spin it off, but I can pre-fill it with almost a quart of new oil when it is time to put oil back in. Though a System 1 or a Canton just needs to be vertical because you can take the top off and suck the oil out if you haven't blown it out with air already (no blowing the engine filter oil back into the engine, though).

Geary · 10-27-2015, 10:51 AM

System 1 really is the safest filter to use (and was developed by my old partner, Jon Karcey).

stownsen914 · 10-27-2015, 12:41 PM

Thanks guys for the input. I've thought about using a System1. Is 30 micron filtering fine enough?

winders · 10-27-2015, 12:50 PM

Sometimes the simplest solutions (Mahle disposable filters) are the best....why do we tend to complicate things like this?

Geary · 10-27-2015, 02:41 PM

Quote:

.. I've thought about using a System1. Is 30 micron filtering fine enough?

I believe engine oil requires 50-60 micron beta mesh screen. While this sounds large, it's been demonstrated that particles of this size don't cause the damage.

Most paper element filters with impressive micron ratings bypass oil on start-up (and high rpm), often washing though stuff that was marginally trapped on the paper. The System 1 "safety valve" virtually never opens.

KaiB · 10-28-2015, 06:33 AM

Quote:

Originally Posted by winders

Sometimes the simplest solutions (Mahle disposable filters) are the best....why do we tend to complicate things like this?

Agreed. Good enough for factory race cars....should be good enough for me.

I've used both Mahle and System 1. Never was concerned about either's performance, but was constantly concerned with the O rings in the System 1.

I honestly believe that oil changes were easier with the Mahle filter also.

stownsen914 · 10-28-2015, 08:23 AM

Quote:

Originally Posted by KaiB

Agreed. Good enough for factory race cars....should be good enough for me.

Do cup cars use off the shelf Mahle filters? Or other factory race cars?

winders · 10-28-2015, 11:00 AM

Quote:

Originally Posted by stownsen914

Do cup cars use off the shelf Mahle filters? Or other factory race cars?

The Cup Cars use a 996 street car filter: 996.107.225.53

Mahle sells a filter that equates to that part number. So yes, Cup Cars use an off the shelf Mahle filter. Is Mahle the OEM for Porsche? I don't know.

Jeff Alton · 10-28-2015, 06:36 PM

Same filter found in 997s, 986s, 987s and Cayennes. Hengst and Mann also make replacement filters for the same number, all are German brands and OE suppliers. I too wonder which supplies Porsche, or if they all do during different purchasing cycles.

Cheers

996TWINS · 10-28-2015, 10:17 PM

Quote:

Originally Posted by winders

The Cup Cars use a 996 street car filter: 996.107.225.53

Mahle sells a filter that equates to that part number. So yes, Cup Cars use an off the shelf Mahle filter. Is Mahle the OEM for Porsche? I don't know.

Yes. The OEM MAHLE filter is the same as the aftermarket MAHLE filter.

stownsen914 · 04:17 AM

Anyone have any more details on the bypass valve opening pressure for Mahle filters (or other brands')? The bypass feature is what has kept me from getting comfortable with using stock-type cannister filters on my racecar - oil pypassing the filter element not only on startup / cold oil but also at high RPM / high flow situations.

I think I've read that the bypass valves open at 20-30 psi? This is of course less than the oil pressure in the oil galleys in the engine, but you might expect the pressure to be less in the filter due to the larger volume there (PV = nRT) ...

Geary · 10-29-2015, 10:09 AM

That's exactly the problem. You can't force 100% of the oil through a paper element, unless the canister is huge.

KTL · 10-29-2015, 11:47 AM

Mann lists their can filter bypass pressure as 2.2 or 2.5 bar in the filters we typically use. Here's the typical '74-'94 oil tank filter that is 2.5 bar

MANN-FILTER Online Catalogue North America - Product Details Oil Filter W 940/29

Here's the 993 filter we use in place of the oil cooler that is 2.2 bar

MANN-FILTER Online Catalogue North America - Product Details Oil Filter W 713/20

stownsen914 · 10-29-2015, 08:03 PM

Thanks Kevin. So opening pressure is a little over 30 psi. Engine oil pressure is obviously well above that in a track car basically all the time. I wonder what pressure the filter is seeing when engine oil pressure is 80 psi? I'd imagine less since pressure is inversely proportional to volume, but I don't know.

Anyone else know?

winders · 10-29-2015, 10:51 PM

The Mahle OC 229 filter I use on the engine console bypasses at 2.2 bar as well.

rs-vic · 09:21 PM

My understanding is the bypass valve in the oil filter opens at a certain differential pressure. Let's use the MANN filter with 30 psi. To me that means when the oil going into the filter has a 30 psi higher pressure than the oil going out, the bypass valve opens. Normally a filter is on the pressure side so there is more pressure on the back side of the filter, but a 911 has the filter on the return to the tank with virtually no pressure on the back side. My question is does anyone know the approximate pressure before the filter? I know we can't go by engine oil pressure as that is a completely separate system. I am assuming the return side is more volume rather than pressure. Considering most filters have a bypass of around 8-14 psi, the 30 psi of the MANN and Mahle makes more sense for use in the return side.

I recently had to rebuild a 911 engine because the rockers were eating the cam lobes. When I drained the oil out of the tank the magnet in the drain plug was full of metal shavings. This got me to thinking about the effectiveness of the filtration on the tank mounted filter.

Currently I am rebuilding a vintage SWB 911 racer. It has the 993 oil console on the engine and a tank up front in the smuggler's box. It only had an Earl's inline screen mesh filter in the return line to the tank. I would like to install a proper filter. I was thinking a Canton would be the way to go as it is a non bypass filter but after reading the comments about it I have decided against it!

I am going to try the 964 oil console with Mahle filter.

KTL · 03-26-2018, 10:06 AM

You're right that the bypass valve in the filter is activated by differential pressure. When the oil doesn't flow well and cannot pass through the filter media somewhat easily, pressure is building and the bypass valve is forced open to allow oil through the filter unfiltered. This happens more often than you think. Like at cold startup and it doesn't even need to be super cold ambient temperature.

Just because a filter is on the pressure side (like the 993 filter housing that replaces the old style engine-mounted oil cooler) doesn't necessarily mean the filter is receiving more pressure. Peak system pressure that you see on your oil pressure gauge is dictated not necessarily by the pump itself, but ultimately by the spring valves in the engine case.

Actually the scavenge side of the 911 pump is much more robust. The volume of oil delivered by the pump is determined by the physical size/length of the pump. Look at any of the pumps (not just the big boys like the GT3 or the 930 pump) and you'll see the size of the pump between the venturi/suction pickup and the discharge port is MUCH bigger than the size of the pump where the oil is delivered to the bearings.

The pressure on the scavenge side can be REALLY high especially when cold. That oil pump is sucking up and pushing out a larger amount of oil from the engine sump and it has to go somewhere. The external thermostat has a built in bypass valve and apparently that is an important thing to have in terms of protecting the scavenge side of the system from very high pressure.

http://forums.pelicanparts.com/911-engine-rebuilding-forum/695694-creating-crankcase-vacuum.html#post6936128

Regarding how the tank drain plug can have major debris on it, I agree that's very concerning. When you look at how the tank takes oil in, that debris has traveled through a lot of places you don't want it to go before it ends up on the bottom of the tank. For that rocker debris to end up in the bottom of the tank, it has to fall via gravity from the cam housings, travel through the oil return tubes, fall into the engine case sump, get sucked up by the oil pump scavenge side, then is pumped out to the external thermostat and finally to the oil filter on the tank. Whatever the filter doesn't filter (because the particles are too small or the filter is in bypass mode) then gets dumped right into the tank where it cascades onto onto a coarse screen. I don't think that screen is any finer than the oil pump pickup screen. So it drops to the bottom of the tank and the last line of defense, which is weak, is the drain plug magnet. So that means any debris not stuck to the magnet is ultimately sucked out of the tank by the pressure side of the pump and therefore goes into the oil pump to do its damage again.

http://forums.pelicanparts.com/porsche-911-technical-forum/982980-diy-oil-tank-cleaning-possible.html#post9873429

The above described route of oil is based on the older engine oil system. The later oil system like the 964 has the oil go through the filter housing (which is separate from the tank) before it goes to the thermostat and back into the tank. But even with the separate oil filter, that doesn't change the outcome. The oil filter still doesn't catch the debris if the filter is bypassing it.