Evaluating our Upgraded Cooling System
This round of dyno testing gave us a great opportunity to evaluate the cooling system upgrades completed last month. Previously, engine coolant temperatures would reach 90 degrees Celsius at the end of a pull. With the FLUIDYNE radiator and the pair of FAL fans in place, we now have dropped this peak temperature to 84 degrees Celsius.
More Power—The Next Steps
With our current setup, more boost pressure is not translating into more power past about 26 to 28 psi of boost pressure. From the looks of it, we are pretty much maxed out on power with the stock engine. Could the turbine housings be the restriction? They quite possibly could be. It could also be the head and cam combination that is limiting power at this point.
No matter how you stack it, we are quickly coming to the point where the stock engine is going to be upgraded. Since the machining and assembly process can be time consuming, we are currently tracking down a low-mileage used engine to build up for the project. The bottom end will receive oversized forged pistons and some high-strength connecting rods. Up top, we plan on having the cylinder head reworked and fitted with a set of Apex Integration camshafts and valvetrain components. Once buttoned together, we are pretty sure that another 100 horsepower at the wheels should be pretty easy to generate.
Since the engine building process will take some time, we plan on doing some work on our current powerplant. By managing the heat in the engine compartment it is our plan to reduce the intake air temperatures going into the turbochargers. For every 11- degrees Fahrenheit that we can reduce the temperature of the air coming into the engine, we can theoretically produce one-percent more power (equates to about 7.5 horsepower at this point). We also want to test out some other products and do some additional tuning to see where we end up with the stock engine. Addressing the rest of the vehicle, we plan on upgrading the stock front differential to a Cusco RS limited- slip unit, installing the OS Giken gear set and dialing in our suspension to make the most of the power. Stay tuned. 
