Element Tuning Time Attack 06 STi Hydra EMS 570 whp

Starting the new Time Attack season we wanted to freshen up the engine and test a few new parts. We started out rebuilding an Element Tuning Pro Comp engine but we switch up the bearings and the compression ratio of the pistons to see how they hold up over a season of racing.

Numbers
Dyno:
Dynojet Altered Atmosphere Gaithersburg, MD
Tuner: Phil Grabow Element Tuning
Wheel HP: 570whp UNCORRECTED
Wheel TQ: 492wtq UNCORRECTED
Baseline: 185 whp 08 WRX
Target Boost: 27 PSI
Target AFR: 11.8 AFR
Fuel: Sunoco 110 Octane with Hydramist (80% water)
Ambient Temp: 50
Elevation: 0

With a new engine I really didn’t want to run it too hard on the dyno so I stopped at 27 psi. I made quick work of the tuning with the Hydra 2.6 software and had all tweaked in as few WOT pulls as possible. In my previous dyno sessions the 1000cc fuel injectors were maxed out so this time around I bumped up the fuel pressure to 55 psi giving me about +20 more flow so I could have a little safety margin on the injector duty cycle. Maximum fuel injector duty cycle was 83% with the 1000cc, A1000 fuel pump, and 55 idle fuel pressure.

I totally forgot that I didn’t like the billet compressor wheel I ran late last year which netted me about 30 whp loss over our standard GT65 wheel (GT35R). With the higher compression and the BC STG 4 cams it looks like we gained back that loss however. The numbers are good for this dyno so I’m happy for now with the improvement.

Car Info
Year
: 2006
Engine Management: Element Tuning Hydra EMS 2.6
Turbo: Element GT65 (testing new wheel)
Intercooler: Custom
Meth Kit: Hydramist 80/20 water/methanol
Injectors: UR 1000cc, Element Tuning Competition Surge Tank, Aeromotive A1000
Engine: Element Tuning Pro Comp: ET Rods, Manley 9.8:1 Pistons (custom ring pack), ET Big Valve Heads +1mm valves, BC STG4 cams, stock block and bore.
Intake Manifold: Subaru RS
Headers: Element
Uppipe: Element Tuning GT65
Downpipe: Element Tuning
CBE: Element Tuning
Other: Element Tuning Competition Catch Can

The BC ST4 cams required me to work on the AVCS mapping as compared to the Cosworth cams. I found that I had to carry the advance farther into the RPM range but in the end the Hydra EMS allowed me to get it exactly how I wanted it.

Having made some new changes to the car I wasn’t sure what the car would weigh in at so I had to have options available for HP so that I could stay in NASA TTU classification. At about 15.3 psi the car made 452 whp which should be low enough to keep me legal in that class.