The Toyota 3S-GTE is a 2.0-liter turbocharged inline-4 engine that powers the Celica, MR2, and Caldina. It’s a long-running engine, having been produced from 1986 until 2007. Machines with the 3S-GTE designation produce 182 to 256 horsepower. For a little inline-4 engine in that period, these are pretty respectable figures.
This article will go through the specifications, performance, and reliability of the Toyota 3S-GTE 2.0 inline-4 engine.
What are Toyota 3S-GTE Engines?
The 3S-GTE is a Toyota inline four-cylinder engine with a displacement of 1,998 cc is based on the 3S-GE. Still, it has under-piston oil squirters and a lower compression ratio to enable the insertion of a turbocharger. Their composition, materials, and features are almost identical to each other.
The Toyota 3S-GTE was manufactured in four versions, beginning in 1986 and halted in 2007. The 3S-GTE engines’ turbochargers are Toyota designs with an internal wastegate design. The exhaust turbine is either ceramic for Japan or steel for the United States. Also, depending on where the engine was meant to be marketed.
The engine was used in the MR2 exclusively in North America and Japan. However, there is no official MR2 with this engine for the European market. Toyota Celica GT- Four, and Caldina GT-T, and GT-Four are also some of the applications of this engine.
Engine Specifications and Design:
- Production Run: 1986 – 2007
- Cylinder Head Material: Aluminum
- Cylinder Block Material: Cast-iron
- Configuration: Inline 4
- Bore: 86.0 mm
- Stroke: 86.0 mm
- Valvetrain: DOHC four valves per cylinder
- Displacement: 2.0 L (1998 cc)
- Compression Ratio: 8.5 to 9.0
- Weight: 300 lbs.
- Maximum HP: 256 HP at 6,200 – 7,600 RPM
- Maximum Torque: 239 lb-ft at 4,800 – 6,400 RPM
General Engine Design:
The Toyota 3S-GTE, being the turbocharged version of the 3S-GE engine, still has four cylinders, numbered 1-2-3-4, the first of which is located next to the timing belt.
Toyota collaborated with Yamaha to make the 16-valve Dual Over Head Cam cylinder head built of aluminum.
A cross-flow intake and exhaust architecture match the pent- roof combustion chambers. The center of the combustion chambers is where the spark plugs are positioned. The cylinders are fired in a 1-3-4-2 sequence using a distributor- based mechanism.
The crankshaft is almost the same as the 3S-GE, balanced by eight weights and spins on five aluminum alloy bearings within the crankcase. The connecting rods, bearings, pistons, and other components all get oil through oil holes in the crankshaft center.
The intake and exhaust camshafts and the oil and water pumps are all driven by a single timing belt. Between the valve lifters of each cylinder and the front of the cylinder head, the cam journal is supported in five places.
The oiler port in the center of the camshaft lubricates the cam journals. In the first two generations, a shim over bucket mechanism is used to modify the valve clearance. A shim under bucket mechanism is employed in subsequent generations.
The pistons are composed of an aluminum alloy with high thermal resistance. If the timing belt fails, an indentation is integrated into the pistons to prevent the pistons from contacting the valves. Snap rings secure the piston pins that hold the pistons in place.
Steel is used for the first compression and oil rings, whereas cast iron is used for the second. The compression rings 1 and 2 keep gas out of the combustion chamber, while the oil ring keeps oil off the cylinder walls and out of the combustion chamber.
3S-GTE Generation 1
The first-generation Toyota 3S-GTE had a single wastegate port and a single entering turbine housing. It was installed in the Toyota Celica GT-Four. Further, the intake charge was cooled by a water-to-air intercooler. The intake manifold is Toyota’s T-VIS, which has eight independent ports and uses inertia to improve engine torque at low and medium speeds.
This happens by closing four ports below a certain RPM and throttle position to increase airspeed, maximize fuel atomization, and widen all eight ports at higher engine loads for better air volume. In addition to that, the first-generation 3S-GTE generation’s air metering is done with an airflow meter, and there is no manufacturing Bypass valve/ Blow off valve.
Air is pumped by a 55 mm throttle body and 7.15 mm intake and exhaust valve lift, while fuel is delivered via 430 cc injectors. With a factory boost of 8-9 psi, the compression ratio is 8.5, producing an equal number of 190 HP and 190 lb-ft.
3S-GTE Generation 2
A double entrance turbine housing with multiple wastegate ports was utilized on the second-generation Toyota 3S-GTE engine. It was installed in the Toyota MR2 Turbo and the second-generation Toyota Celica GT-Four.
Further, Toyota continued using the top-mounted air-to-air intercooler in the Celica and a side-mounted intercooler in the MR2 that cools the intake charge. The rally homologation Celica (GT-Four RC in Japan, Group A Rallye in Australia, or Carlos Sainz Limited Edition in Europe) had a top-mounted water-to-air intercooler and a hood vent instead of the hood scoop found on non-homologation ST185s.
The T-VIS intake manifold and Air Flow Meter are kept in this version.
The SW20 MR2 Turbo has a factory bypass valve, whereas all Celicas do not. The compression rating is higher than the previous with 8.8, and this version generates 232 HP and 224 lb-ft of torque.
The injector and throttle body sizes from the previous generation are carried over to the second generation. The ST185 and MR2’s boost is raised to 10-11 psi, while the ST185RC’s boost is increased to 16 psi. The lift of the intake and exhaust valves has been raised to 8.2 mm.
3S-GTE Generation 3
The Toyota C20b turbo is used in the third-generation Toyota 3S-GTE engine, which is similar to the second-generation but with a slightly better turbine housing and bigger compressor wheel.
Across all applications, a factory bypass valve is fitted along with a water-to-air top- mounted intercooler. A similar design was used in the ST185RC WTA. In this mechanism, it cools the intake charge, with the ST205 WTA being black and the ST185 WTA being silver with a black center.
This version foregoes T-VIS in favor of a standard four-runner intake with the same port shape and size as the Naturally Aspirated engine – 3S-GE – but bigger injector holes for side feed.
3S-GTE Generation 4
A distinct CT15B turbocharger is used in the fourth-generation engine. The Toyota Caldina GT-T AWD Wagon was equipped with this powerplant. The thing with the fourth-generation Toyota 3S-GTE engine is that rather than having a separate turbine housing following the cylinder exhaust manifold, the exhaust housing is cast into the cylinder exhaust manifold.
As a result, the CT15 can also be used backward but only the third-generation 3S-GTE cylinder head, but neither the first nor second generation.
An air-to-air top-mounted intercooler cools the intake charge, which was supplied through a redesigned side-feed intake manifold.
This version had 550 cc injectors and a coil-on-plug ignition system. The boost pressure stays at a range of 13-14 psi. However, the overboost fuel cut has been increased.
The fourth-generation engine produces 256 HP and 239 lb-ft of torque.
3S-GTE Generation 5
The turbo in the fifth-generation engine is the same as in the fourth generation. The Toyota Caldina GT-Four was built with this generation. There are only small variations between this engine and the previous generation, and because the ST246 is only available in a few regions, little is known about it, and few people are aware of it.
Some of the key changes that this engine has undergone are the injectors which are longer in order to be closer to the intake ports. Further, the intake manifold switches back to a center-feed design, with an air-to-air intercooler installed on top. This intercooler is a little smaller than the previous generation, and it’s angled a little differently from the others; it is angled towards the front of the vehicle.
On top of that, the coil-on-plug ignition is restyled in this generation and is incompatible with the ST215 ECU. The valve cover is unique in which the oil filler hole
is on top of the exhaust camshaft rather than the intake camshaft, which is the first time in the 3S-GTE series.
Other changes include the absence of an oil cooler as well as OBD2 diagnostics. Despite the downsizing of many components, this generation’s output remains at 256 horsepower and 239 pound-feet of torque.
Applications of Toyota 3S-GTE Engine:
- 1986 – 1989 Celica ST165 190 HP and 190 lb-ft
- 1990 – 1993 Celeica ST185 MR2 232 HP and 224 lb-ft
- 1994 – 1999 Celica ST205 MR2 JDM 242 HP and 224 lb-ft
- 1997 – 2001 Caldina ST215 256 HP and 239 lb-ft
- 2002 – 2007 Caldina ST246 256 HP and 239 lb-ft
Engine Potential, Tuning, and Upgrades
You simply should make a boost up. For that, you need to buy 3S-GTE Generation 3 connecting rods, intake system and other parts like front intercooler; blow-off valve for increased power when needed, external tuner such as HKS ECU, Brian Crowder 264/264 camshafts which give more torque at lower RPM’s by providing shorter duration times. With these upgrades, your engine can now produce 320 HP and 17-18 psi of boost.
If you are looking to up your power, then the stock turbocharger won’t give it to you, so replace the older one with a high-performance 3S-GTE turbo kit. It’s the only way. For installation, purposes buy an 800 cc injector and port head over before installing larger valves in them.
All of these upgrades are sure to give an incredible boost in power. Forged pistons will take things from stock HP level all the way up above 450-ish HP when installed correctly on top-quality cylinder heads cast.
Connecting rods made out of AIM rod steel composite material means they’ll be able to contain higher temperatures under pressure without breaking or cracking while also being lighter weight than ever before, which helps reduce frictional losses during rotation along cog leg shafts inside combustion chambers where most gasoline engines burning occurs at peak RPM.
Problems Surrounding Toyota 3S-GTE Engine:
The 3S-GTE 2.0 inline 4 engine is a reliable overall choice for your car, but it’s worth noting that many of these engines are over twenty years old and can’t keep up with modern-day demand.
It’s very reliable, and it doesn’t take long to break in, but there are drawbacks like needing constant maintenance because of its age or mileage – especially if you tune your car with modifications.
Here are some issues that you might deal with the Toyota 3S-GTE Engine:
1. Engine Block Issues
Let’s start with the most obvious ones, and it is worth mentioning the blocks of the engine. A cast-iron block is used. Because of the amazing strength of cast iron, this is a popular design. When it comes to the 2.0 turbo inline-4, though, engine block breaking is a hot issue. Block cracking is more frequent on early generation 3 engines before 1997. However, it can happen on any 3S engine.
The main problem appears to be between cylinders two and three. Because of the thin casting, the block is prone to fracture in that location. Toyota strengthened the block, making newer engines less prone to problems. Furthermore, in completely stock engines, 3S-GTE engine blocks seldom break. Because of the greater cylinder pressures in modified engines, this is a common occurrence.
2. Turbo Oil Leak
The 3S-GTE engine’s oil leaks aren’t attributable to any design defects or other issues. Many gaskets, seals, and other components in all engines are prone to deterioration over time. As a result, oil leaks in 3S-GTEs are more of a problem of age and mileage than anything else.
Since some of the components made up of the engine is rubber-like, they deteriorate over time and accumulate mileage. With age, these gaskets and seals grow brittle, shatter, and oil leaks occur. The primary seals, oil pan, and valve cover gasket are all typical places for oil leaks.
With years of continuous use and ramping up miles, it’s common for oil leaks to appear on many engines. Don’t be deceived by low-mileage specimens; aging gaskets and seals may be just as damaging. The point is that all Toyota 3S-GTE engines are past the point when oil leaks are a typical occurrence.
Despite the reputation, turbo engines have come a long way throughout the years. Toyota’s 3S-GTE has been one of the most reliable and longevity models for cars to date. Though it suffers from a few major design flaws, especially its generation 3 block, this engine is far more than specifications can offer.
That is also what makes this engine unique among newer technologies like hybrid vehicles or battery electric motorsports technology today.
On 3S-GTE engines, be wary of block cracking, especially while altering and upgrading the engine. Oil leaks and turbo failures, on the other hand, are regular problems. However, these are largely age-related issues rather than any intrinsic defects or difficulties with the 3SGTE.
But overall, the engine is solid and capable of lasting longer than any of its peers. It paved the way for reliable turbo engines that we have today for an inline engine.