Supra (A70)
1986-1993 / Coupe / Japan
The A70 Supra was Toyota's grand touring flagship, powered by a series of straight-six engines including the turbocharged 7M-GTE that produced 230hp. It was a big, comfortable car that could cover ground quickly and confidently, bridging the gap between sports car and GT in a way that few Japanese cars had attempted before.
Often overlooked in favour of the A80 that followed, the A70 is now being recognised in its own right as a genuinely capable grand tourer. Australian examples with the turbo engine are particularly interesting and still relatively affordable compared to the A80's stratospheric prices. The 1JZ-GTE engine swap from the Japanese-market cars is a popular upgrade that brings modern reliability and tuning potential. The A70 Supra offers a lot of car for the money, and values are beginning to reflect that.
Thinking of buying a Supra (A70)?
What to look for, what to pay, what to avoid.
What to watch for.
Head Gasket Failure
Common Engine, 7M-GTE (Turbo)
Head Gasket Failure
CommonThe head gasket blows, allowing coolant into the combustion chambers and/or oil passages. White smoke from the exhaust, coolant loss without visible external leak, overheating under boost, milky oil on the filler cap, and bubbles in the coolant overflow tank. In severe cases, hydrolock (coolant filling a cylinder and bending a connecting rod on startup).
Toyota designed the 7M head with only 10 head bolts, insufficient clamping force for the cylinder pressures generated under boost. The factory composite head gasket degrades over time and eventually fails. Thermal cycling accelerates the process. Every 7M-GTE will eventually blow a head gasket on the factory bolts, it's a matter of when, not if.
Strip the head, machine it flat (check for warpage, common after overheating), install a Cometic multi-layer steel (MLS) head gasket, and secure it with ARP head studs (part number 203-4205). The ARP studs provide dramatically more clamping force than the factory bolts. While the head is off, replace the valve stem seals. Retorque the studs to ARP's specification (typically 85 ft-lb with ARP moly lube). Total cost: $1,500-2,500 including machining, gaskets, studs, and labour.
Low Oil Pressure at Idle
Critical Engine, 7M-GTE (Turbo)
Low Oil Pressure at Idle
CriticalOil pressure drops below 10 psi at hot idle. The factory oil pressure warning light may flicker or illuminate at idle, particularly in traffic on hot days. The engine may develop bearing noise (deep knocking from the bottom end).
The oil pump wears internally over time, reducing output at low RPM. The oil pressure relief valve spring weakens with age, allowing the valve to open too early and dump pressure back to the sump. Using incorrect oil viscosity (too thin) compounds the problem.
Start with an upgraded relief valve spring, this is a $30-50 part and a 30-minute job. It's a bandaid but effective if the oil pump is only mildly worn. For a proper fix, replace the oil pump ($200-400 for the pump, plus labour to access it). An oil cooler relocation kit ($150-300) moves the oil cooler from the factory position to a more exposed location for better cooling, which helps maintain oil viscosity in hot conditions. Use 15W-40 or 10W-40 oil, do not use 5W-30 in a high-mileage 7M.
CT-26 Turbo Failure
Common Engine, 7M-GTE (Turbo)
CT-26 Turbo Failure
CommonLoss of boost pressure, excessive oil smoke (blue/grey) on startup or deceleration, whistling or grinding noises from the turbo, and oil in the intercooler piping.
The CT-26 has a limited service life. Shaft bearings wear, allowing the compressor and turbine wheels to contact their housings. Seal wear allows oil past the turbo seals into the intake (compressor side) or exhaust (turbine side). Running the turbo hard and shutting down immediately (no cool-down idle) accelerates seal and bearing failure.
Rebuild or replace. A CT-26 rebuild runs $400-800 at a turbo specialist. For anyone planning to increase power beyond stock, this is the time to upgrade. Common replacements: Garrett GTX3076R for mild builds (300-450 hp), BorgWarner S362 for mid-range (400-550 hp), Garrett GTX3582R for serious builds (500-700 hp). Upgrading from the CT-26 requires a new exhaust manifold (or adapter), oil and water lines, and an ECU retune. Budget $2,000-5,000 depending on the turbo choice.
Cooling System Inadequacy Under Boost
Critical Engine, 7M-GTE (Turbo)
Cooling System Inadequacy Under Boost
CriticalCoolant temperature climbs rapidly under sustained boost, particularly in traffic or on hot days. The temperature gauge sits higher than normal and doesn't recover quickly.
The factory radiator was adequate for 1986 driving conditions in Japan but struggles in Australian heat, particularly with any power increase. The fan clutch wears and stops driving the fan at sufficient speed. The intercooler and piping add heat to the engine bay.
Replace the radiator with an aluminium performance unit ($300-600), this is one of the highest-value modifications on a 7M-GTE car. Replace the fan clutch if it spins freely by hand when cold ($150-300), or convert to an electric fan setup with a quality controller ($300-600). Ensure the fan shroud is intact and properly sealed to the radiator, gaps allow air to bypass the radiator core.
Fan Clutch Wear
Common Engine, 7M-GTE (Turbo)
Fan Clutch Wear
CommonThe engine runs hotter than normal, particularly at low speeds and idle. The cooling fan doesn't seem to pull much air through the radiator.
The viscous fan clutch uses silicone fluid that leaks out over time as the internal seals wear. Once the fluid level drops, the clutch can't engage fully and the fan freewheels.
With the engine cold, try to spin the fan by hand. A good fan clutch should have definite resistance, you shouldn't be able to spin it easily. If it freewheels, replace it. Aisin or OEM Toyota units are preferred ($150-300). Alternatively, delete the clutch fan entirely and fit a quality electric fan with a thermostatically controlled relay ($300-600 for the conversion).
Head Gasket Failure (Less Common)
Critical Engine, 7M-GE (Naturally Aspirated)
Head Gasket Failure (Less Common)
CriticalJoin the conversation.
Common questions.
What's the difference between MA70 and JZA70?
The chassis code tells you which engine the car was built with. **MA70** is the turbo model with the 7M-GTE engine (3.
Will the head gasket definitely fail on my 7M?
On the 7M-GTE turbo: yes, eventually. It's a matter of when, not if.
How much does a 2JZ swap cost?
Expect to spend $8,000-15,000 for a DIY 2JZ-GTE swap using a secondhand engine, doing the work yourself. That breaks down roughly as: - **Engine (2JZ-GTE, secondhand from Japanese importer):** $3,000-6,000 depending on mileage and accessories included - **Gearbox (R154 or V160):** $1,500-4,000 (R154 is cheaper) - **Engine mounts (aftermarket kit):** $400-800 - **Wiring harness (adapt or aftermarket):** $500-1,500 - **ECU (standalone like Haltech or Link, or adapted factory):** $500-2,500 - **Intercooler and piping:** $500-1,500 - **Radiator, hoses, cooling plumbing:** $300-800 - **Exhaust manifold, downpipe, exhaust:** $500-2,000 - **Driveshaft (custom or adapted):** $300-600 - **Miscellaneous (fluids, gaskets, mounts, bolts):** $500-1,000 - **Tuning:** $500-1,500 A shop build doubles the total cost due to labour.
Is the W58 gearbox strong enough for a turbo build?
No. The W58 was designed for the naturally aspirated 7M-GE and is marginal even at stock turbo torque levels.
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