Last month we started our engine buildup that should withstand whatever amount of horsepower we decide to throw at it.
Speed Force Racing prepared the bottom-end components, including Swain Tech-coated JE pistons, ARP main studs, Pro-Gram billet main caps, and Cryo-Science's cryo-treatment to the crankshaft, engine bearings and the Pauter billet connecting rods. Though it's a touch overkill, we'll play on the safe side for engine longevity.
Our goal is to build a block that won't need to be torn down for many years to come; the same goal applies to the Supra's cylinder head.
The first order of business with the cylinder head is the internals. We ordered Ferrea Racing components for that extra peace of mind. The 1 mm oversized valves should substantially increase overall head flow. Specifically designed for forced-induction motors, Ferrea competition valves use a nickel-based alloy with a unique heat treatment process for maximum heat resistance and a tremendous amount of tensile strength.
The dual valve springs are manufactured from high-grade alloys and are heat-treated and stress-relieved to dramatically increase spring life. Strong and lightweight Ferrea titanium retainers and valve locks, along with factory valve guides and seals, top off our cylinder head components. Combined, these components should allow our engine to rev well past 9000 rpm.
Speed Force Racing also performed the cylinder head work . SFR's Tim Richards had the exhaust and intake chambers ported and polished to match the intake and exhaust manifold gaskets. While the exhaust side was polished smooth the intake port was left with dimples for better fuel atomization.
To accommodate the new oversized valves, SFR had the combustion chambers touched up to prevent shrouding of the valves, which would otherwise prevent the gases from properly passing through the chamber. Each valve and seat went through a full-radius cut for optimal valve-to-seat seal and improved flow characteristics. The full-radius valve job provides a smoother transition from the port to the seat than a three- or five-angle valve job, maximizing airflow.
Once the head was assembled it was time to take it back apart. The bare head and valves were sent to Swain Tech Coating for their thermal barrier coating. The head received coating in the combustion chambers and in the exhaust port. The valves got a coat on each of the valve faces of the same coating as on our JE piston domes. This helps keep heat from soaking into the head, instead keeping the heat inside the combustion chambers where it belongs. Keeping more of the heat in the combustion chamber promotes a more complete burn of the air/fuel mixture, producing more power, as well as increasing engine longevity.
The Ferrea valve springs and retainers were sent to Cryo Science to be cryogenically treated to add even more life to each component. By slowly freezing each part to 300 degrees below zero, the molecules are brought together making the metal super dense. When the part is slowly warmed back up the molecules evenly disperse, providing consistent strength throughout the part.
Using its proprietary EDS (enhance durability and strength) Heat Wave treatment, cryo-tempered components reportedly see a 30 - 50 percent decrease in wear and a 100 percent increase in fatigue resistance. Considering it's only about $60 to do all the springs, the process is well worth it.
With all the parts back in hand, SFR went to work assembling the head. Since the valve ports had a very fine layer of thermal coating, each valve had to be lightly spun inside each port (called lapping) to remove the coating from the seats. Once the head was assembled it was time to mate it to the short block. For a good seal we used a metal, quad-layered 1.6 mm head gasket from HKS, which will be more than enough to handle the cylinder pressures we'll be throwing at it.
Since the factory head studs stretch and fatigue over time we are using ARP fasteners to attach the head to the block. Being over twice as strong as the factory units, ARP studs help prevent the head gasket from blowing out and spraying coolant all over the pavement in case the head lifts during a high-boost run.
Because the 2JZ-GTE engine has solid lifters and our head has gone through some major changes, we needed to double check the valve shims to be sure we are maintaining factory-spec clearances. Using the factory manual as guide it is fairly easy to cross-reference the current shim thickness with each current clearance to get the corresponding new shim size. It turned out that all of our intake shims needed replacing. But the exhaust shims were all within spec.
At this point we contacted Champion Toyota of Houston, Texas. Parts Manager, Thomas Sowell was extremely helpful in getting us our engine parts when we needed them. He sent the proper shims so we could install the factory cams right away. (Don't worry, we've already got a set of wilder cams we'll be testing shortly.)
Once the head was fully assembled, Speed Force Racing technicians got underway putting the rest of the engine together. Since our goal is to build a sound engine, some additional parts and pieces were ordered from Champion Toyota. All of which are a good idea to replace when rebuilding a high-mileage Supra motor.
New oil and water pumps replaced the high-mileage units. Additionally, the majority of the coolant and the hard-to-get-to-later-on heater hoses were replaced. New TRD motor mounts, also from Champion, help keep the engine secure and vibration free.
Before everything could be bolted together we needed new gaskets, engine seals and o-rings. Fortunately for us, Champion Toyota sells a full engine gasket and seal kit for the 2JZ-GTE. Having all the gaskets and seals delivered in one large box was truly a load off our minds.
Now that we've got what we believe to be a motor that should withstand a beastly amount of power, we're ready to move onto what we've been anxiously anticipating since Day 1 of the project.
By the next installment we'll hopefully have the engine running, broken in, tuned and hopefully baseline-tested on a chassis dyno. We'll also go into detail about our custom fuel system as well as the star of the Sound Performance turbo system.
Following that we'll discuss our cooling system, feature new aerodynamics and test a set of cams against our low- and high-boost baselines. Stay tuned, the fun has just begun!
Author's Note: Special thanks to Champion Toyota's Thomas Sowell and Cryo Science's Travis Young for their patience in dealing with all of our urgent, last-minute requests.