The Piper valve springs and retainers were also WPC treated. WPC treating greatly improves the springs' fatigue life and reduces their operating temperature. The springs' life can be improved over 100%. 

Most people don't know it, but valve springs get very hot at high rpm. WPC treating the retainers improves the fatigue life and adds some lubricity to the spring interface. Springs often rotates in use. 


WPC treatment was also applied to the Piper camshafts. The cams are the second biggest contributor to overall engine friction, and WPC treatment makes a big difference here. 

WPC also makes a huge difference in the camshaft and follower life, easily more than doubling it. 


After WPC treatment, we sent the JE pistons off to be Swain Coated. We used Swain's Gold Coat thermal barrier coating on the piston crown and PC-9 low friction coating on the skirts.

Swain Tech’s GoldCoat thermal barrier coating is a three-layer coating consisting of a proprietary combination of different ceramics. Swain’s Gold Coat is designed to withstand the stress of forced induction motors. GoldCoat reduces heat transmission to the underlying metal by 20-40 percent. This helps protect the piston from detonation-induced heat as well as reduces thermal expansion. Since pistons do not have the benefit of water jackets like those in cylinder heads, keeping heat out of them is a good thing.

Swain Tech’s GoldCoat transfers heat through the surface of the coating, but not past it to the underlying metal. This promotes even heating across the piston crown, thus helping to reduce hot spots and promoting an even burn for good flame travel.

Swain PC-9 piston skirt coating is made of molybdenum disulfide and tungsten disulfide in a heat-conducting polymer resin matrix to make a tough, lubricious surface. PC-9 resists “creep” under thrust loads. Creep is an engineering term for force induced distortion. This causes the coating to smear and stick under load and causes tolerances to change. PC-9 is also heat conductive. Since the primary way a piston cools itself is through conduction to the cylinder walls, you do not want to insulate the skirts! 

The coating itself tightens the piston to wall clearance by about 0.0012" then burnishes in and we feel that this will help us get the tightest possible piston fit for less slap, less friction, happier rings and long life. 


We sent our heads off to Portflow Design to get the valve job done on their Newen CNC valve seat cutting machine.

The Newen cuts a true radius valve job that blends the combustion chamber to the valve seat to the port in a smooth flow increasing radius. The Newen also opens up the port in the valve area for more overall area for gas flow. With some hand blending in conjunction with a Newen cut valve job, you can have a port that flows almost as good as a fully ported cylinder head.


Once we got our heads back from Portflow, Howard blended the top cut, Newen made into the combustion chamber using a rotary cutter then smoothing it with cartridge rolls. 

Howard used an old stock valve to protect the newly cut valve seat while doing this operation. 


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Tuesday, January 30, 2018 2:17 AM
ARP bolts used => need to check for the need of a line hone ( that is written on their website and is usually the reason for main bearing failures on 2jz, SR, RB and so on). Since it spun a rod bearing it may not be the cause, but you might want to check this, otherwise it might end us being the next catastrophic engine failure cause.

Mike Kojima
Mike Kojimalink
Tuesday, January 30, 2018 8:36 AM
of course, we checked it with the ARP studs.
Dan DeRosia
Dan DeRosialink
Tuesday, January 30, 2018 9:16 AM
Do you know offhand what size supercharger pulley that was? Sucks about the oil pump gear... didn't the 4AGs used to do that? I don't think that was the sort of heritage Toyota/Subaru was intending to hearken back to...
Tuesday, January 30, 2018 10:05 AM
What weight/type of oil did you use?
Tuesday, January 30, 2018 10:25 AM
WPCing the rings does not hamper their ability to seat?
Mike Kojima
Mike Kojimalink
Tuesday, January 30, 2018 11:02 AM
WPC treating of the rings make it take slightly longer to seat but it's not an issue. If you clearance the engine right and have the right cylinder wall prep, the rings seat almost instantly. With WPC it takes two instants.
Mike Kojima
Mike Kojimalink
Tuesday, January 30, 2018 11:02 AM
I believe the engine was running 15w/50
Tuesday, January 30, 2018 11:14 AM
Sad to hear You got to experience the shortcomings of the FA20 firsthand.
Tuesday, January 30, 2018 2:35 PM
Do the cylinder heads drain well?
Mike Kojima
Mike Kojimalink
Tuesday, January 30, 2018 2:46 PM
We are wondering about that.
Wednesday, January 31, 2018 1:52 PM
If you look at the WRC EJ blocks (which are wetsump, although the sump is very well developed), the cyl head oil drains are enlarged a good amount.
Mike Kojima
Mike Kojimalink
Wednesday, January 31, 2018 8:20 PM
Thank you for that info!
Monday, February 12, 2018 12:23 PM
So Mike,

Did you take Twist's advice from part one and do something with the pan to at least try and prevent the oil starvation issues?

Also, second hand info...but heard those Piper Camshafts are cracking/breaking..
Saturday, February 17, 2018 5:25 PM
Toda Racing already makes an upgraded oil pump gear for the FA20.
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