Roger Clark Motorsport in Canada
AFR Autoworks has supplied Roger Clark Motorsport (RCM) parts for many years. RCM builds the answers to the problems EJ-powered Subarus run into at power — oiling, timing accuracy, cylinder four heat, rotating assembly strength. Their slogan, "Driven by Passion", covers a history that runs from WRC and rally to the Gobstopper 1, 2 and 3 time attack cars, and every part in the Power Parts range has been through that programme before it reaches the market.
Oil system
Oiling is where most hard-driven EJ engines give up. The RCM 4-Stage Dry Sump System for the EJ20, EJ22 and EJ25 is the full solution — we run one on our own drag car, and we wrote up how it works here. Short of that, the Group N baffled sump pans control surge on track, the RCM High Performance Oil Filter is built specifically for high-output Subaru engines, and the engine oil and power steering cooler kits keep temperatures in check on 2008–2014 WRX and STI.
Timing, cam pulleys and valvetrain
Many EJ Subarus left the factory with Bakelite cam gears. They're a known failure point, and RCM's alloy camshaft pulley kits (also available for non-AVCS engines) replace them properly. The Dual Bearing Eccentric Adjustable Idler Set lets you hold cam timing accurately after the block, heads or head gasket thickness have been changed — which is most built engines. We also stock RCM timing belt kits with OEM, Dayco, Cosworth, HKS, Tomei and STI belts, the high-grip tensioner, belt guides, and the Spec C profile camshafts for V7–V9 STI.
Rotating assembly and stroker kits
For the bottom end, we carry RCM/Omega piston sets in high compression, low compression and low expansion, RCM/Arrow H-section rods and the Xtreme H-section set for higher power, and the Arrow billet crankshaft.
The 2.1 stroker kits for the EJ20 come in three levels: budget, standard forged, and billet. The step up buys crank and rod material, not displacement — pick the level that matches your power target and how long the engine has to live at it. If you're not sure, ask us.
Turbos and manifolds
The RCM600 Subaru Twin Scroll Precision Hybrid Turbo pairs Precision's 58mm Gen 2 turbo with RCM's own twin-scroll turbine housing for the strongest stock-location twin-scroll setup we've run: over 560 whp (650 bhp) on our dyno. The same approach is available as the RCM500 on Precision's 55mm turbo with the RCM twin-scroll housing and wastegate. We also stock RCM/Precision stock-location billet turbos, RCM stainless tubular manifolds in equal-length, unequal-length and twin-scroll configurations, the twisted turbo up/downpipe kit, and the 67mm electric throttle with reversed WRC manifold.
STI Sports Parts
We can order the full range of STI Sports Parts — Subaru Technica International's own upgrades on factory components. Group N engine mounts, Group N strut mounts and the triple pillow ball lateral link sets are the ones worth knowing about for a street car that sees track days.
RCM on the AFR drag car
Our GC8 drag car runs RCM parts throughout: the 4-Stage Dry Sump with the under-bonnet installation kit, the Eccentric Adjustable Idler Set, alloy/steel vernier cam pulleys for V7–V9, the thermal spacer kit, the cylinder four cooling mod and RCM billet half moon seals. It makes over 900 whp and revs to 9,500 rpm, and it keeps doing it. That's the reason we sell these parts rather than something cheaper — we've already proven them on our own car.
Frequently asked questions
Do you ship RCM parts across Canada and the United States? Yes. We ship throughout North America from Red Deer, Alberta.
Which RCM oil system suits a street car versus a race car? A baffled Group N sump pan and the high performance oil filter cover most street and occasional-track cars. Sustained track use, high-rpm builds and drag cars are where the 4-Stage Dry Sump earns its cost.
Why replace the factory cam gears? Many EJ engines came with Bakelite cam gears, which are a known weak point. RCM's alloy pulley kits replace them with a serviceable, accurate alternative.
What's the difference between the budget, standard and billet 2.1 stroker kits? The displacement is the same. The levels differ in crank and rod material and specification — match the level to your power target and how hard the engine will be used.
Can AFR build or install an RCM-equipped engine? Yes. We build and tune EJ engines in our Red Deer shop, and we run RCM parts on our own cars.
