WR35 GTR Performance Parts
WR35MP GTR PERFORMANCE MID-PIPE
WR35TC GTR GR6 TRANSMISSION INTERCOOLER
WR35OP GTR HI VOLUME OIL PAN
WR35DC GTR REAR DIFFERENTIAL COOLER
WR35DC-F GTR FRONT DIFFERENTIAL COOLER
WR35MP GTR PERFORMANCE MID-PIPE
Order Form: WE35MP Order Form
WR35MP Willall Racing Mid-Pipes replace the centre resonator and pipe section on the R35 GTR which make it sound muted and quiet, most unlike a performance car. Hand made in Australia using high quality Australian Stainless Steel our Mid-Pipes have the utmost craftsmanship and engineering put into their production. Each WR35MP is tested for fitment on a GTR before shipping so you can have a perfectly aligned production piece anywhere in the world.
Long section flex pipes are used to ensure the interface between the engine and exhaust is not stressed or broken even in severe motorsport applications. The merge section also uses an inbuilt oval diffuser to direct each bank of exhaust gas into the rear of the system with the least turbulence. Gains are significant over stock, with the actual horsepower number dependant on the tune in place. An important bonus is the weight saving from installing WR35MP. Not only is there less exhaust back pressure for more flow and performance, but there is also a 50% (15lb or 7kg approx.) reduction in overall weight.
The best part of WR35MP though is the sound. Gone is the quiet and low hum of the stock GTR replaced instead by a glorious engine note reminiscent of the high powered early GTR models that helped forge the legend. There is no cabin drone, no loud noise at cruising speed, just a genuine powerful voice for your GTR.
Listen to the GTR Mid Pipe by viewing the video below.
Here is another great video of the WR35MP Willall Racing R35 GTR Mid Pipe recorded by our Czech customer 'Kislik'. Not satisfied with us only having the tone of WR35MP posted at idle and free-rev, he went out and made the really nice film clip at full throttle. Well done Kislik!
CUSTOMER COMMENTS
These comments have been posted directly to Willall from customers that have used WR35MP on their R35 GTR and have not been altered in any way other than to remove vehicle identity.
WR35TC GTR GR6 TRANSMISSION INTERCOOLER
Order Form: WR35TC Order Form
Instruction Sheet: Instructions.doc
Designed to deliver cooler operating temperatures to improve reliability and longevity of the R35 GTR GR6 Transmission, WR35TC is ready to fit your GTR. Pictured is a look at WR35TC from under the car showing the unique high quality billet aircraft aluminium finned sump that works in conjunction with a sophisticated pump and cooling core to achieve the best possible cooling result. Highly engineered and with every consideration put into its design WR35TC the thermostatically controlled promises to reduce transmission operating temperature without the pressure control problems other GR6 cooling system designs have encountered.
NEW RELEASE: WR35TC-F Front Mounted transmission cooler also available. Designed for those that run aftermarket exhaust systems on their R35GTR the –F front mounted cooler option stops the cooling process being interrupted by heated air from the exhaust system. When GR6 transmission cooling with an aftermarket exhaust make sure you pick the WR35TC-F no cost front mount cooler option on the order form (see WR35TC pictures for actual cooler views).
Coming in each and every WR35TC kit are the following components:
Billet Aluminium CNC sump with Willall Racing Transfer
Bar and Plate 450mm x 100mm x 75mm cooler core custom end tanks with -6 fittings
High pressure heat resistant lines and -6 / JIC high pressure fittings (around 4 feet)
Mounting bracket CNC machined from billet aluminium
GR6 Cooler transfer Pump assy
Wiring harness (front to rear of vehicle from the battery)
WR series 200F Temperature switch
Replacement fill plug CNC machined
Magnet mounts CNC machined with captive O-rings
Silicone hose - custom crimp fittings CNC machined
P rubber lined Mounting Clamps x 5
Intercooler Mounting bracket
Mounting bolts x 4
Instruction Manual
TESTING
Testing the WR35TC GR6 Transmission Intercooler correctly was always going to present a challenge, as with fluid handling it's not as simple as 'switch the cooler on its cold', 'turn it off its hot'. Also the car has to be driven HARD, there is no point in taking it easy as the temperature of the transmission is directly proportional to the lap times.
The Willall Racing GTR was tested to the limit of the RE0570 tyres and brakes (Endless pads were used). Our test driver is very quick in the car due to lots of practice and could reasonably argue our 1:17.5 lap pace at the South Australian Mallala circuit is similar to 2:10 or so at a track like VIR. Over 1.5 tanks of fuel were used in the test session showing exactly how hard the GTR was driven.
Test 1: WR35TC Cooler Status ON
A test to check the outright cooling ability of WR35TC and find the 'stabilise' point of the transmission temperature
Ambient: 75F - Trans Start: 195F
Lap1: 215F
Lap2: 226F
Lap3: 237F
Lap4: 240F
Lap5: 242F
Lap6: 241F
Test 2: WR35TC Cooler Status OFF
With the cooler turned off this is the raw data of temperature build up in the GR6. It gives you an idea of our punishing conditions
Ambient: 75F - Trans Start: 194F
Lap1: 220F
Lap2: 231F
Lap3: 248F
Lap4: 265F
Lap5: 272F
Test 3: WR35TC Recovery OFF and ON
Letting the transmission reach almost critical temperature we then turned the cooler on to check temperature recovery
Ambient: 76F - Trans Start: 181F
COOLER OFF
Lap 1: 231F
Lap 2: 240F
Lap 3: 252F
Lap 4: 264F
COOLER ON
Lap 5: 261F
Lap 6: 255F
Lap 7: 252F
Lap 8: 250F
Lap 9: 249F
GENERAL WR35TC PICTURES
WR35OP GTR HI VOLUME OIL PAN
Order Form: WR35OP Order Form
Instruction Sheet: Instructions.doc
If there is one thing the GTR lacks for extreme duty use its a big engine oil capacity. The VR38DETT comes with a 5.8 quart engine oil capacity and works the engine oil hard with big temperature loading and duty cycle due to missing out on additional capacity. With this in mind we have re-modelled the original pressed tin factory pan into a two piece high volume billet aluminium sump, complete with cooling fins and removable bottom tray that takes the GTR oil capacity out an extra 1.7 quarts to a total of 7.5 quarts, reducing overall oil temperature and giving a greater reservoir for the engine to draw from.
Included in the WR35OP kit is an oil pickup extension to the move the factory pickup deeper into the new pan, which is also sealed with an O-ring, once more to give a low maintenance and high quality result. Fasteners are Stainless Steel SHCS (Socket Head Cap Screws).
In Final position the removeable lid fastens to the WR35OP oil pan giving a perfect seal and lining the factory drain plug up over the cutout in the underbody making for simple and easy maintenance.

WR35DC GTR REAR DIFFERENTIAL COOLER
Pricing: Price List
Instruction Sheet: Instructions.doc
Keeping the rear differential temperature of the R35 GTR in check and at acceptable levels requires external cooling, and we have achieved this with a fresh new Willall Racing cooling product.We call our R35 GTR Rear Differential cooler WR35DC and it's fully engineered from top to bottom as all our products are to work seamlessly on a track orientated or hard driven R35 GTR without cutting or drilling anything. Here are the parts that come in the complete kit -
As you can see this is a fully comprehensive kit as per other Willall Racing products. Nothing needs to be cut, shut, moved, or modified to fit these parts, with the result being to cool the high operating temperatures of the rear differential that can run to an excess of 270F in the right hard driven conditions (and closer to a constant 210F when WR35DC cooled). A CNC machined mounting bracket, 13 row cooler, high pressure and temperature crimped lines and every other nut, bolt, fitting, and mounting part you need.
Here is where WR35DC mounts, up behind the rear differential, but before the exhaust system in holes that already exist in the factory R35 GTR crossmember. There are a couple of reasons for this mounting position, but the very first is to get air from the underbody transmission air scoop, and the second is to allow for ANY conventional aftermarket exhaust system. Correct - WR35DC will mount with any aftermarket exhaust, regardless of brand. We know this as it sits behind the sway bar travel arc without any interference.
Some neat touches that show the full level of the engineering we have put into this product are -
1) A new air deflector system from under the rear differential that bolts in place of the factory part and provides adequate clearance.
2) A 'Jacking Point' adatper that bolts to the undertray and means you can still jack the car off the factory point without damaging anything or pushing against any part of the WR35DC Rear Differential Cooler system when changing tires at the track.
For those that already have a Willall Racing WR35TC or TC-F GR6 Transmission Cooler we have a 'double pump' loom extension that plugs in place to drive the differential pump without any wiring modification. If you have the WR35TC or TC-F then the WR35DC will be triggered by the existing transmission temperature thermostat that is already in the system. Otherwise its a manual switch system we provide with the kit with an indicator light to show when the cooling pump is activated.
If you subscribe to the above and have an existing Willall Racing WR35TC or TC-F Transmission Cooler we also have a 'double shot' pump bracket that holds both the existing transmission cooler fluid pump and the new WR35DC differential cooler pump.
TESTING
Test data from Mallala International Raceway for WR35DC R35 GTR Rear Differential Cooler - General testing observations - Weather cool and mild, 'green' track conditions.
Testing equipment - JK Thermocouple unit
Temperature probe placed in the differential pump line to measure temperature at the outlet of the differential (pre-cooler)
Test 1: WR35DC Cooler Status OFF
Mode: A test of differential temperature without cooling
Ambient: 64F
REAR DIFFERENTIAL TEMPERATURE (Transmission Temperature in brackets with WR35TC-F Cooler running)
Lap1: 258F (203F)
Lap2: 266F (212F)
Lap3: 277F (232F)
Lap4: 286F (236F)
Lap5: 292F (242F)
Lap6: 294F (244F)
STABILISE REAR DIFF TEMP - 290F
PEAK TRANSMISSION TEMPERATURE - 244F
Test 2: WR35DC Cooler Status ON
Mode: Testing the WR35DC Differential Cooler effect on both differential and transmission
Ambient: 66F
REAR DIFFERENTIAL TEMPERATURE (Transmission Temperature in brackets with WR35TC-F Cooler running)
Lap1: 247F (207F) * WR35DC Switched on at the end of the first lap to get 'up to temperature'
Lap2: 241F (216F)
Lap3: 230F (228F)
Lap4: 232F (236F)
Lap5: 231F (234F)
Lap6: 229F (237F)
STABILISE REAR DIFF TEMP - 230F
PEAK TRANSMISSION TEMPERATURE - 242F
If you study the data long enough you will see that quite obviously the rear differential is in need of major cooling, as it builds temperature very quickly, and then acts as a preheater on the back of the transmission assembly. Removing heat from the differential then not only preserves the life of the differential fluid it has also shown - in this test - to have a positive effect on transmission temperature at the same time. The value of adding such a system to the GTR is clear from these positive and decisive test results.
WR35DC-F GTR FRONT DIFFERENTIAL COOLER
Pricing: Price List
Instruction Sheet: Instructions.doc
A small fluid capacity and the ability to punish the lubricant from running at near 300F temperatures cooling the front differential of a hard driven GTR is essential. The use of a compact high efficiency cooling core allows us to integrate our new WR35DC-F Willall Racing Front Differential cooler into the high airflow 'nose-cone' area of the R35 GTR seamlessly. Bolting alongside the existing power steering cooler, and coming with its own CNC machined and anodised aluminium bracket, there is no drilling or cutting to fit the cooling core, just the removal of the top access cover with a few clips.
Coming in each and every WR35DC-F kit are the following components:
Front mounted cooling core
Machined billet CNC Pump mount bracket
High pressure and temperature lines and -6 / JIC high pressure fittings (around 4 feet)
Differential Cooler transfer Pump assy
Wiring harness with manual switch
Replacement fill plug CNC machined
Replacement drain plug CNC Machined
Silicone hose - custom crimp fittings CNC machined
Mounting bolts and hose clamps
You can see the full core exposed here in this closeup photography and see how it sits in the airstream of the vehicle for maximum cooling effect and little of what we call 'cross pollution' of heated air with other system coolers.
Another custom CNC machined and anodised aluminium bracket mounts the fluid transfer pump in existing mounting location which means that the whole thing bolts straight into place, with only the lines needing to be run between the cooler, the pump and the front differential. Installation is simple, and wiring is either via an extension of your existing cooling system or a complete loom with an in-car activation switch.
All high quality JIC crimped fittings are used for zero chance of leakage, along with our 350F and 500psi rated flexible transfer line, which when combined with our durable protective covering gives a long life high temperature solution. Note the temperature strip indicator in place...this will be used for 'after' testing. Pre tests showed that capability for consistent 300F+ in the front differential without a cooling strategy.