Carbon Aero Tuning A 670hp WRX Time Attack Weapon

What goes into building one of the fastest Time Attack Open Class Subaru WRX's on the scene, that is still EJ powered?

This 30-40 psi Precision Turbo & Engine boosted EJ25 powered GC8 Tyre R is an 1190kg and 500kw+ time attack build that caught our eye at the @World Time Attack Challenge in a large part thanks to the carbon fibre aero package from Topstage Composites that was under development throughout the event.

Liam Hooper in his Car Mods Australia sponsored & Dahtone Racing supported weapon runs us through some aspects of the build including the IAG Performance fire-lock cylinder head sealing package (aka fire rings) along with the MoTeC Global controlled torque split and how it is one of the most important features of the build when it comes to retaining speed in the corners to balance out the lack of power on the straights compared to some of the competition in the open class.

The Racewire Tasmania prepped electronics package also includes a MoTeC ECU, PDM, paddle shift control and dash display with the M150 ECU also running a torque-based firmware package from Racetech Performance with the help of a Samsonas Motorsport sequential helping put the power to the ground and enabling the driver to keep the RPM up and in the boost range. On that note also discussed is the need to not have high boost pressure/cylinder pressures at to low of an RPM in order to keep the EJ intact, along with a conservative 8,200 limit.

The general weak points of a Subaru WRX for this application are touched on too, engine internals which include custom pistons, boost control, and how shock potentiometer data is used to help dial in both the MCA Suspension and aero package, along with how the aero is basically tuned from being a brand new setup.

It wouldn't be a Subaru video without discussing engine lubrication too, and as you'd expect this build runs a dry sump system with this specific one being a Daily Engineering unit running faultlessly.

Liam and his team took out 7th place in the open class by the end of the event with a 1:32.3370, also making them the 2nd fastest WRX out on track.

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TIME STAMPS:
0:00 - Liam Hooper | Car Mods Australia
0:23 - Why A Subaru?
0:44 - GC8 Type R Coupe Base
1:00 - Weight Reduction: 1190kg
2:30 - High Powered EJ Engine Recipe
4:20 - Head Cylinder Sealing: IAG Fire-Lock
5:08 - Oversized Head Stud
5:14 - What Is A Fire Ring/Fire-Lock?
6:13 - Engine Internals
6:58 - Cam Choice
7:15 - Boost Control
7:39 - Peak Cylinder Pressures
8:15 - RPM Vs Boost
9:08 - Oil Supply - Dry Sump
10:22 - Samsonas Gearbox
10:42 - Center Diff Control
11:32 - Electronics Package
12:00 - Torque-Based Firmware
12:37 - Aero Package - Topstage Composites
13:42 - Shock Pot Data
15:00 - Front Canard Tuning
16:08 - Have Everything Setup To Be Able To Adjust
16:54 - Thanks Liam!
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