It's been 10 years since I dropped the 1JZ into my 244, and with Christmas around the corner I thought I'd treat myself and spend a bit of money on it.
The problem:
Toyota utilise 2 x CT-12A turbochargers on the non-VVTi 1JZ-GTE engine, which run in parallel. The design of the dump pipe means that the exhausts from each turbo collide into each other before exiting to the exhaust, causing a significant restriction and power loss. The turbos also utilise ceramic exhaust wheels, which have a glass ceiling of around 14psi, after which they become unreliable (read: fly down the exhaust in many pieces).
Solutions:
- Remove the turbos and change the ceramic exhaust wheels to steel, which will allow higher boost.
- Purchase or fabricate a new dump pipe, designed so exhaust gases flow more freely.
- Remove entirely the twin-turbo set up and replace with a single turbo.
In this case, the cost for steel-wheeling the turbos and fabrication of the dump pipes was too high for the potential power gain, so I opted to go the single-turbo route.
The project:
Remove both turbos, manifolds and all associated plumbing. Replace with a quality exhaust manifold, larger turbo and external wastegate. Fabricate dump pipe to suit, modify oil and water lines to suit, modify intercooler plumbing and add a catch can to replace current crank case pressure relief system. Due to budget restrictions, the set up must run with the standard Toyota ECU for the time being.
The parts:
- Garrett GT3582R, 0.82 rear housing
- 6BOOST steam-pipe manifold
- Turbosmart 45mm external wastegate
- Studs, nuts, fittings, hoses etc
Some photos are taken with my mate's ancient iPhone 4, so apologies for lack of quality.
The turbo
Exhaust manifold
Stock turbo and manifold removal
Casualties
All the parts removed
CT-12A turbos removed, a closer look. Very small wheels!
Manifold and turbo test-fit for clearance. The compressor housing will need to be rotated before final fitment.
Size comparison of CT-12A and GT3582R
Wastegate pipe welding and fitment
More to come as the work progresses...
