16

We Look Inside Fredric Aasbo's Papadakis Racing Toyota Corolla iM Drift Machine

by Mike Kojima

 

It is really hard to build a competitive car in Formula Drift nowadays. The rules set is mature, and the competition is ruthlessly tough. When even the best teams develop a new platform, it can take a whole season to sort a new chassis out. A radically different chassis can take a couple of seasons for even a top team to get competitive. Not so for Papadakis Racing and their Rockstar Toyota Corolla iM that they built for 2015 Formula Drift Champion Fredric Aasbo.

In a feat of engineering, Stephan Papadakis and company has built a car that is an entirely different platform that has proven to be extremely competitive right out of the box. Having a brand new car on an unproven platform be immediately competitive has not happened until now in the modern age of drifting, which I consider to be post-2009.

It also helps to have a mature team and Papadakis Racing's crew dates back to the days of import drag racing, where Stephan was always successful and could be counted on to turn out innovative and well-engineered cars.

Stephan was kind enough to let us dig deeply into this marvelous machine and give us full disclosure on its innards and specs, so without further adieu, let's go!

 

The car's engine bay is quite interesting. The Toyota 2AR-FE engine sits longitudinally with the car converted to RWD. This is legal under FD rules because the Corolla is available as an AWD model in some markets. The Papadakis 2AR-FE engine is super high-tech and has amazing power density, pumping out around 1000 hp and 850 lb/ft of torque on Nitrous. 

The engine's block is sleeved by Golden Eagle with 1/2" ARP 625+ head studs and billet main bearing caps and contains a Sonny Byant Billet stroker crank. Forged 10.5:1 JE Pistons are hung on Carillo rods with Calico coated ACL rod bearings and OEM Factory coated mains. The factory MLS head gasket is used although additional coolant passages are drilled in it for improved cooling.

 

The engine's cylinder head is ported by Portflow Design who also does the special radius valve job with wider than typical 45-degree valve seats for improved reliability. The head has Supertech intake and exhaust valves with the intake valves made of 21-4N stainless that is black nitrided. The exhaust valves are made of heat-resistant Inconel with a sodium filled stem.

The head is machined to use larger valve springs to accommodate the 9000 rpm rev limit without float. Papadakis Racing titanium retainers are used. The head has been converted to use mechanical lifters and the custom roller cam followers are shaft mounted for additional high-rpm stability. 

The camshafts are a special grind developed by Papadakis Racing and have 0.450 lift and 232 degrees of duration @0.050". Cam timing is fixed on the exhaust side while the intake uses the factory VTC system allowing the AEM Infitiy ECU to control the intake cam with 45 degrees of command authority. 

The engine uses the stock Toyota/Denso direct fire coils controlled by the AEM Infinity ECU. This has enough juice to fire the plugs even with a lot of boost pressure and nitrous induced cylinder pressure.

 

The Papadakis Racing iM uses a big Borg Warner EFR 9174 with a free flowing 0.92 A/R twin scroll exhaust housing to pressurize the intake air. The turbo is largely responsible for the engine's 1000 hp.

For drifting, fast throttle response from the engine is very important for controllability when being completely sideways in close proximity to another sideways car. The EFR9174 has many spool time and lag reducing feature starting with a high flow, forged billet CNC-machined extended tip compressor wheel. The forged billet wheel has better mechanical properties, such as superior grain and grain flow. This makes the compressor wheel stronger.   

The improved strength from forging allows the use thinner blades for better flow, and the extended tip gives the inducer more "bite" which also speeds spool. The stronger material also allows the designed to shrink the hub size for better aerodynamics and flow as well.

The billet compressor wheel sits in a ported shroud compressor housing, which fights compressor surge by allowing inlet air to recirculate through the compressor as the flow is starting to back up. This is especially important when running a turbo with nitrous as the Papadaki IM does. The extra exhaust gas volume that nitrous creates can drive the turbine hard overspeeding the compressor past the surge line at lower rpms and put it into damaging surge, which the ported shroud housing can prevent.

On the turbo's hot side, a CFD designed investment cast stainless steel exhaust housing with a Titanium Aluminide super lightweight turbine wheel provides the drive for the compressor. The turbines exotic intermetallic material reduces rotating inertia to a minimum. Titanium Aluminide has the properties of both a metal and a ceramic, having the strength and ductility of a metal with the lightweight and temperature resistance of a ceramic. This lightweight turbine wheel combined with the twin scroll housing can reduce spool time by over 30 percent. 

The final part of Borg Warners lag reducing technology is the EFR9174's ball bearing center section which reduces friction and improves life under high thrust loads caused by high boost and nitrous. The spool time can be improved as much as 20% by using ball bearings here. 

 

The Borg Warner 9174 EFR Turbo sits on a custom twin scroll exhaust manifold by Full-Race Motorsports. One 38mm Tial wastegate is used to control boost per side of the twin scroll system.

Twin Scroll turbos utilize pulse energy of the engine to hit the turbine with 4 discrete, evenly spaced pressure pulses to get the most drive possible out of the exhaust stream.  A twin-scroll system can speed spool time by as much as 25%.

 

Page 1 of 10 Next Page
Bookmark and Share
Comments
SM_Clay72
SM_Clay72link
Tuesday, October 17, 2017 9:45 AM
Gorgeous build quality and attention to detail. Thanks for the insights Mike.

Glad to see the coils I am running on my 280whp 1JZ are probably the most power ready parts I have bolted to the car!
warmmilk
warmmilklink
Tuesday, October 17, 2017 3:45 PM
I don't get the CNC-machined front billet motor mount. its a big beefy piece bolted in 4 places but its a pretty flimsy looking connection on the chassis side... just one bolt on with not much area for whats basically the flange to keep it from rocking...

a part is only as strong as its weakest link, and that mount's flange looks pretty weak compared to the rest of the mount. I mean if it works, it works... I'm mostly asking cause it got its own picture and called out as "stiff and strong". that connection to the chassis doesn't look all that stiff or strong. I'm not saying its not strong enough, but other than looking pretty (and it does look pretty), I don't see anything special about it.
Mike Kojima
Mike Kojimalink
Tuesday, October 17, 2017 6:55 PM
The threaded rod plug welded into the tube is pretty stiff and strong.
Stephan_Papadakis
Stephan_Papadakislink
Wednesday, October 18, 2017 9:52 AM
I'll try to answer some questions here in these comments.
@warmmilk
The way we build engine mounts now a days is to secure most, if not all of the twist/ rotation at the motor plate between the engine and transmission, which connects solid to the frame rails. We have found if the front engine mount or the transmission mount is too stiff, when the chassis twists, the engine block or transmission will become a stress member, which the 2AR and G-Froce transmission were not designed for. A problem can arise with changing dimensions inside the engine or transmission of bearing clearances, bores, etc. which has lead to problems.
We use a urethane transmission mount, which just supports the rear of the transmission, and a "weak" in twist front engine mount that just supports the weight of the engine from gravity.
The front mount is also an over complicated design since I was trying to up my ability with CAD and machining knowledge by practicing with a complicated design. It is also made from 7075T6 aluminum ;)
Thank you
warmmilk
warmmilklink
Wednesday, October 18, 2017 12:41 PM
@Mike Stunt Cock Kojima
the threaded rod (pun intended) pay be stiff (again, pun intended) but the mount area is still small, so there's only so much the the threaded rod can do...

@Stephan_Papadakis
that makes sense. That mount didn't look like it was designed to provide a lot of twisting resistance, thats why the caption under the pic didn't make all that much sense to me.
It is a sweet looking piece, as are a bunch of the other machined anodized pieces in the build.
and I think you guys got robbed out of first place in Seattle.
SM_Clay72
SM_Clay72link
Wednesday, October 18, 2017 1:01 PM
I just read the pictures. The squiggly bits are confusing.
Jeff Naeyaert
Jeff Naeyaertlink
Wednesday, October 18, 2017 1:04 PM
we should have just done a video tour of the car for you SM_Clay72 🤔 ..hmmm
HPGJustin
HPGJustinlink
Sunday, October 22, 2017 7:02 PM
hey, figured I would get a quicker reply here compared to youtube.

Is there any downfall by placing the engine to far back from the shock towers?

Im still in the process of installing my M272 Mercedes v6 into 190e, I'm open to any engine placement. I can run it where the center weight of the engine it dead middle of the shock towers, or I can move the engine back enough that the front of the engine timing cover is inline with the shock towers. Its going to be an all around car, DD, Drift, Time attack, anything and everything.

Any help and info like always is much appreciated.

Thanks, Justin M.
Mike Kojima
Mike Kojimalink
Sunday, October 22, 2017 10:57 PM
As far back as the rules allow is best.
HPGJustin
HPGJustinlink
Monday, October 23, 2017 8:55 AM
Thanks for the reply, as this isn't going to be a competition vehicle. More for daily and showing of my fabrication. But when we have a drift event or I can drive a track day at PIR I will.

Not worrying about rule books or tech, can placing the engine to far back effect a cars characteristics so much it may ruin the handling?

Obviously I'm not planning on putting my engine in the middle of the car, but i can scoot it back a pretty significant amount, Ive looked around and read of the pros and cons.

Thinking I'm going to need to find someone with corner scales to see the change in weight distribution before i make a decision.

Thanks again Mike

Justin m
Insta @hpgjustin if you are interested in the build
warmmilk
warmmilklink
Monday, October 23, 2017 11:18 AM
pushing the engine back can only improve handling. you want all the weight to be as centered as possible. that way you get the best weight distribution for all 4 tires and reduced momentum of weight being thrown around as you turn and drift and stuff
Post Comment Login or register to post a comment.

MotoIQ Proudly Presents Our Partners:



© 2018 MotoIQ.com