Extreme Engine Tech, Building a High Boost 2JZ with Brian Crower and JE Pistons-Part 1

Extreme Engine Tech, Building a High Boost 2JZ-GTE with Brian Crower and JE Pistons-Part 1

by Mike Kojima

Building a 2JZ-GTE is not new on the pages of MotoIQ.  Pablo Mazlumian documented the building of a pretty healthy 2JZ in his Project Supra chronicles over the past couple years. We like the 2JZ powerplant.  It is a strong, robust powerplant capable of sustaining well over 1000 hp and has been competition proven in everything from time attack to drifting.  It is still quite a viable engine 23 years after it was introduced.

The 2JZ has a stiff and rigid iron block for good bearing life and head gasket seal.  The crank has huge journals and lots of overlap. With 7 main bearings the crank is well supported.  With a 120 degree firing sequence and perfect primary and secondary balance the 2JZ is inherently well balanced at high rpm.  This is because the front and rear three cylinders move as a mirror images of each other but 360 degrees out of phase.  This eliminates rocking vibration.  The 3 planes of cylinders firing at 120 degree intervals eliminates secondary vibrational forces.

The 120 degree firing order also makes it easy to design effective turbo manifolds as you can treat the engine like two three cylinders for a good efficient twin turbo setup or good pulse conversion with a single turbo.  This makes for good turbine efficiency. 

So our prior engine build effort was to make a lot of streetable power, but the goal for this engine will be to make a lot of reliable power for drag racing. Because of the attributes we were talking about the 2JZ is a great platform for this.  For our drag motor we can have less power compromises for street uses. Check out what we are starting with.

 
The heart of our build is a stroker crankshaft by Brian Crower. The BC crank is a proven part used by just about every 2JZGTE engine we know of running in Formula D. We are running BC's lightweight billet crank, which at 48 lbs is 12 lbs lighter than their standard crank.  We will be running a 94mm stroke up from the stock 86mm. BC has 96mm stroke and standard 86mm stroke cranks available as well. BC cranks are made of a solid billet of 4340 steel, a high nickel, high chromium and high molybdenum alloy know for its extreme strength and toughness. BC cranks are ground on state of the art US made 5 axis Mazak 300-IV CNC machines with tolerances controlled down to 0.0001″. After machining the cranks are stress relived and shot peened which helps fatigue resistance. It is also Magnaflux particle inspected for cracks and flaws, then nitrided for surface hardness, toughness and fatigue resistance. Finally the journals are micropolished for a low friction bearing surface. The BC crank has all the normal high end race prep work already done and is good to go out of the box.
The Brian Crower lightweight crank is differentiated by its teardrop profiled counterweight shape which not only sheds weight, but helps reduce windage losses by slicing through the oil cloud in the crankcase better as well as pairing off pounds. The internal areas of the journals at the neutral axis are partially drilled out to reduce weight as well. As you can see above, the journals have really large radius filets which greatly help strength and fatigue resistance. The crank oil passages are gun drilled in a cross pattern to give priority feeding to the rod bearings. The oil holes are CNC ground in a teardrop profile for better oil distribution on the bearings. With a 94mm stroke and a 87mm bore we will be getting 3.4 liters of displacement from our engine.
We also got Brian Crower's billet oil pump drive gear.  The drive gear is stronger than stock which is good because torsional vibration is an issue with inline 6 cylinders at high RPM and the oil pump is usually the first part to suffer. The stock oil pump drive gear is usually stuck on the stock crank as well and you stand a good chance of damaging it trying to get it off. 
We chose Brian Crower's top of the line BC625+ connecting rod for our motor. The BC625+ rod is designed to handle over 300 hp per cylinder and we will be needing that. BC rods are 5-axis machined from 4340 billet and are two stage shot peened, heat treated and magnaflux inspected.

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