Problems In Need Of Solutions
Solutions provided by PHR
The 2JZ engine was not designed for single turbo setups, although in todays world, we all know single turbo is the king of the 2JZ world. The return inlet from the radiator was not oriented to accomodate big singe turbo setups, and therefore with it's position, we can have some real problems installing a top notch turbo manifold.
The Powerhouse Racing Lower Waterneck Rotator is a great solution for turning you waterneck away from your turbo and manifold, and down behind the alternator away from problems.

Runner Interference
With the lower waterneck in the factory position, there are two problems. First, the waterneck gets in the way of the runners on many turbo manifolds.

Turbo Interference
Second, the waterneck is blocking the ideal routing for the compressor outlet and intercooler piping.

Solved
The PHR Lower Waterneck Rotator moves the waterneck out of this terrible position, allowing the manifold to fit properly and the compressor outlet to be free of obstruction.
Improvement In Design
New Revision
Cooling system functionality
The thermostat has two functional parts to it:
the thermostat valve itself, which opens at a certain temperature, and at the
same time, a valve that closes off the radiator bypass hole when the thermostat
opens.
Normal operation of the thermostat and waterflow is as follows: when the
thermostat is closed, the bypass hole is open. This flows the water directly
out of the head and back to the waterpump at low coolant temperatures, like
during warmup and no water flows through the radiator. Once the coolant reaches
the thermostat opening temperature (usually 180 degrees or 160 degrees), the
thermostat opens and the bypass hole is closed off, forcing water through the
radiator, and cooling it down.
The Factory Design
Take a look at the following picture to see what hole needs to be blocked off when the valve opens.
With other brand waterneck rotators,
and even the earlier version of the PHR lower waterneck rotator, positioning of
the thermostat has had to be moved away from it's proper location in the
housing.
With these designs, the
thermostat is moved away from the bypass hole to accommodate the rotator
itself, and the thermostat installs in the lower waterneck boss. This
position of the thermostate makes it so the bypass hole can never fully close. Even
when the thermostat is open, the bypass hole is not closed and a large amount
of the water is not allowed to go through the radiator and be cooled. This reduces
the efficiency of the cooling system.
A Fix For The Problem
The NEW Powerhouse Racing Lower Waterneck Rotator solves this problem. The position of the thermostat remains in the factory location, allowing the thermostat to close off the bypass hole like it is supposed to and moving flow of all the water through the radiator, maximizing cooling system efficiency.
Hose Solutions
Once you've installed the waterneck rotator, you now have to address the hose routing. You CAN make the factory hose work, but it doesn't work well. It ends up way too long and routing is terrible and twisted in unapealing ways. You want a hose that is designed for a rotated waterneck, and PHR has produced one specifically for this need.
Specifications
Vehicle Fitment | |
---|---|
Make | Toyota, Lexus |
Model | Supra, GS300 (Aristo) |
Chassis Code | A80, S160, S161 |
Generation | MKIV (Mark 4), 2nd Gen |
Fitment | |
---|---|
Engine | 2JZ-GTE, Non VVT-i, 2JZ-GTE, VVT-i |