This is not really a “quad turbo” setup like on a Veyron, even if it sounds cool to call it that in the post’s title. It’s a custom compound turbo setup that works in a similar way to that used on diesel engines, with two turbos of different sizes working together to create the kind of boost levels and engine responsiveness that couldn’t normally be achieved with huge turbos alone.
First, at lower revs, two TD06-17C turbos start creating boost to get the whole thing going.
Once the boost levels are sufficient with the smaller turbos, these two T88-34D turbos positioned right up the front of the engine bay create even more boost with the eventual aim being something well over 3 bar.
The boosted air then flows through the intercooler and into the intake manifold. Somewhere in the middle of all that is a water/methanol injection system to keep the inlet charge somewhat cool.
The thing on the right is a supplemental radiator that is plumbed into the heater core lines, since the car has no HVAC system. Despite being a bit ugly, Takuro says it works quite well.
All those snails need to be supplied with exhaust gas obviously, so Takuro fabricated a complicated exhaust manifold where the front three cylinders feed one TD-06/T88 compound pair, and the rear three feed the other pair. Each turbo has its own individual external wastegate which is used to control the staging of the turbo boost.
Here we have some brake bias gauges, a huge mechanical boost pressure gauge, the methanol injection system over on the right, and a big old-school Trust mechanical boost dial.
The 2JZ is fitted with a six-speed Supra transmission. The purple thing is the fuel filter.
In the back, we have the tank for the methanol injection mix, battery box, 100hp fuel pump, NOS bottle (only used as an intercooler and radiator cooling spray at the moment)
The rear mounted radiator and electric power-steering pump, scavenged from a Toyota MR-S.
The side-mounted exhausts are for the four external wastegates.