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Quote:

Originally Posted by gtr06 (Post 7918908)

which oil filters have given you the best results? I just use a standard fram one.

I used to use a Fram one.

Till it literally blew up on me. THAT was a fun experience.

I've been using the K&N one you can get at Advance, they've been tested to work really well.

I pulled this off of the Supramania website. It has a lot of good information and is worth a read.

Quote:

Originally Posted by jDub

I've been meaning to talk about this...just have not gotten around to it. Since it was really off topic in the other thread, I created this one. Keep in mind, this discussion is going to center around relatively stock 7M motors to those in the 400'ish HP range. You start building a motor for the big HP numbers, you will need some mods to the oil/filter system to provide the flow needed. First, I'll discuss how a conventional full flow filter works.

Full flow filters are just that...oil under pressure flows through the filter media back to the motor. For the 7M engine reference this TRSM diagram:
http://www.cygnusx1.net/supra/Librar...tion=LU&Page=2

The oil pump moves the oil from the pan directly to the filter bracket. It is pumped through the filter 1st, then is moved to the engine parts that require it. Note the relief valves...the 1st one is on the pump itself. Over ~40 psi oil is vented back to the pan...this is a regulator that prevents over pressurization of the system at high rpm. The second is on the oil filter bracket...this one directs oil to the cooler on a turbo motor. It functions in the 30-40 psi range...below this, there is no oil going to the cooler. The third is a fail safe in case the filter becomes clogged...it directs unfiltered oil back to the motor in this case. Not a likely event if you're using a good filter with a by-pass valve.

Filter flow is important...you want one that flows 7-9 GPM to provide adequate flow to the 7M. If you shim the pump to provide more pressure, you will need to modify the filter set-up or you risk putting the filter into by-pass. If this happens, you will be running unfiltered oil. Really high oil pressure is not necessarily a good thing

Once oil enters the filter through the outside holes, it is forced through the filter media and exits out the middle hole that screws to the housing..full flow filters work from the outside in. At the dome of the filter there is a spring that holds the media cylinder against the base. At the top or bottom, a good filter will have a spring loaded by-pass valve...if pressure inside the filter overcomes the spring, the oil flows around the media back to the motor. At the base, a good filter will have an anti-drain back valve. Think of this as a check valve...it allows oil to flow in through the outside holes, but not in reverse. This is to keep the filter full and prevent momentary oil starvation to the engine as the filter fills up.

Here is some info on micron ratings vs. efficiency for filter media:
http://www.filtercouncil.org/techdata/tsbs/89-5R3.html

It just so happens I did an autopsy on a PureOne filter I was using as a tranny fluid filter to see if I had any metal present. It was not on the motor very long...it's purpose was to initially filter the ATF before I installed a Trasko by-pass filter. I'll talk about it 1st...here are the pics:

http://img1.putfile.com/thumb/4/10822152940.jpg
http://img1.putfile.com/thumb/4/10822153047.jpg
http://img1.putfile.com/thumb/4/10822152990.jpg
http://img1.putfile.com/thumb/4/10900150254.jpg

In the 1st pic the parts are shown in order left to right...casing, spring, media, and base. The 2nd pic shows the top of the media cylinder...the leaf spring goes on top of this. The green "button" in the middle is the by-pass valve...both the spring and by-pass valve are at the dome end of the filter. The 3rd pic shows the feed end of the filter...the red disk is the silicone rubber diaphragm-type anti-drain back valve (ADBV). If you look at the filter base you can tell how it would cover the outside holes preventing back flow from the filter.

Why do I like this filter? Take a close look at the media...it has numerous pleats that are close together. This means this filter has a larger surface area than most. The media itself is one the best out there for conventional filters...it is constructed of a dense paper/glass fiber and will catch particles at 99% @ 20 microns and 96% @ 10 microns efficiency. The largest media pore size is 42 microns, the smallest is 10 microns. The silicone ADBV is high quality and effective.

The only downfall for this filter is the by-pass valve location. It's at the top of the filter...if it were to function, oil would wash over the outside of the media possibly picking up debris and carrying it to the engine. Not a huge downside due to the unlikely event the by-pass valve would ever function...the media would have to be clogged for this to happen. This is a very well designed filter overall.

The Wix is also a very high quality filter...here's a pic:
http://img1.putfile.com/thumb/4/11323491433.jpg

The surface area and number of pleats is slightly less than the PureOne. The media is also not quite as fine...the largest pore size is 58 microns, the smallest is 19 microns. This cuts down the efficiency...Wix says it catches 98 % of particles 25 microns or larger. However, it also flows a bit better than the PureOne for the same reason. This filter also has a high quality silicone ADBV similar to the PureOne. The biggest difference is the location of the by-pass valve...it is at the entrance of the filter. If it functions, the oil by passes the media completely avoiding the situation in the PureOne.

Other quality filters are Mobil 1 and K&N...both are Champion Labs filters...note how similar they are. Here's the pics:
http://img1.putfile.com/thumb/4/10912083411.jpg
http://img1.putfile.com/thumb/4/10912030931.jpg
http://img1.putfile.com/thumb/4/11317255637.jpg

The Mobil 1 uses a synthetic media with excellent filtration ability...construction is similar to a PureOne, but more robust and also uses a heavy duty silicone ADBV. The K&N uses conventional media, but has more surface area than the Mobil 1 or PureOne...the ADBV is also silicone. Plus the K&N has the nut welded on the dome for easy removal. Both of these filters have the by-pass valve at the top of the filter. These filters are comparable to the Wix or PureOne...the difference is cost...bang for the buck, the Wix and PureOne beat them.

Another very popular filter here is Toyota OEM...it's actually a Denso filter made in Thailand. Here's some pics:

http://img1.putfile.com/thumb/4/10911305451.jpg
http://img1.putfile.com/thumb/4/10911305432.jpg
http://img1.putfile.com/thumb/4/10911305599.jpg
http://img1.putfile.com/thumb/4/10911305578.jpg

Note the lack of an end cap on the media cylinder...the pleats are glued together on the ends to prevent flow from getting around the media at the top/bottom creases. The by-pass valve is built into the top leaf spring and relies on the leaf spring to hold it against the center tube...it is inferior to the PureOne and even more so to the Wix. The ADBV is black nitrile. Compare construction of this filter to the PureOne above...there's a huge difference. Plus the media used in the Denso filter continues the trend...it is slightly better than a Fram Extra Guard. This filter was designed to be mass produced cheaply...not near the quality of the above filters. Next time you hear "Toyota filters are FTW!", point this thread out to them

There is a difference in Toyota filters made in Japan. If you can find them (I've never seen one for a 7M at a US dealer)...for other Toyota car they are called TRD Denso Filters and are rather expensive. If you're motivated, you may be able to cross reference to one that will work on the 7M...really easy to do if you have a remote oil filter set-up. They are a resin type media and are very well constructed. Here's a pic...the resin type is on top:
http://img1.putfile.com/thumb/4/10913293258.jpg

This brings me to the Fram filters...take a look at the pics:

http://img1.putfile.com/thumb/4/10912130025.jpg
http://img1.putfile.com/thumb/4/10912030747.jpg
http://img1.putfile.com/thumb/4/10912030745.jpg

You want to avoid Fram Extra Guard filters like the plague. They are very cheaply made (ends of the media cylinder is cardboard), media surface area is 2/3 that of the PureOne, the media filtration ability is average at best, and the ADBV is black nitrile vs. silicone. The Fram Tough Guard is better with a cheaper version of the silicone anti-drain back valve and average filtration ability. The Fram Extended Guard is actually pretty good...but it is still cheaply constructed...note all 3 have the by-pass valve built into the leaf spring like the Toyota/Denso filter. Quality doesn't hold a candle to the Wix, PureOne, Mobil 1, or K&N filters in this respect. Fram filters are cheap for a reason...if you want to go cheap, use a STP (better media) or Wal-Mart SuperTech.

Here's a comparison of a few of the above filters:
http://www.lesabret.com/filters/filter.html

Here's who makes the various filters out there:

Fram

Fram Extra Guard (std)
Fram Tough Guard (different media?)
Fram X2 (Silicone ADBV, Fuzzy media)
Fram Extended Guard (same as the X2)
Mileguard (Jiffy)
Honda (although some are alleged to be made by Filtech)
Chrysler line up except for the Cummins
Pennzoil (Extra Guard)
Deffense
Canadian Tire (Extra Guard)

Champion Labs

Bosch
Car and Driver
Deutsch
Mobil 1 (syn media)
STP
SuperTech
K&N
Valvoline filters
Mighty
Service Champ
Lee
AutoZone Value Craft
AC Delco (some)
VW (some)
Warner
Luberfiner
Trust

Wix

Carquest Blue
Carquest Red (lower quality with nitrile ADBV)
Napa Gold
Napa Silver (lower quality with nitrile ADBV)
Kralinator (in Canada)
ALLIANCE (Freightliner aftermarket)

Purolator (Arvin Meritor)

Purolator Premium Plus (nitrile ADBV)
Purolator PureOne (silicone ADBV, different media)
Havoline
Maxlife Valvoline (some)
Group7
Promotive
Powerflow
Quaker State (less media)
Advanced Auto Total Grip (less media)
Pep Boys Pro-Line
MotorCraft
Superflo

Hope that helped...