3S-GTE/3SGTE Engine Swap
Naturally Aspirated (N/A) to Turbo (3SGTE) Conversion
The MKII MR2 came in two different models. The base, naturally aspirated model is powered by a 2.2L 5SFE 4-cylinder engine that can also be found in a Toyota Camry of similar vintage. The more well known and acclaimed model is the MR2 turbo. Powered by a 2.0L 3SGTE 4-cylinder that is force fed by a CT-26 turbocharger the Turbo models are extremely potent and capable of running excellent numbers. So what can you do if you are an owner of a N/A MKII MR2? Swap it!
Thats right! The 3SGTE engine can be easily transplated into vehicles originally equipped with the 5S-FE/5SFE powerplant. What are the advantages? First of all there is the insurance factor. The non-turbo models have significantly lower insurance premiums than their turbo counterparts. The VIN will still reflect the car's non-turbo origins and you insurance will therefore be lower, despite the fact that you are essentially running around in an MR2 turbo. Is this illegal? We're no legal experts and its probably always best to make sure that your bases are covered, especially if you want to get the full value for your car if you're in an accident, but there are plenty of people paying N/A insurance for swapped cars.
Another advantage is chassis-integrity and wear. The MR2 turbo is a quick car from the factory. Factory quickness often proves to be too much of a temptation to some owners who feel it necessary to leave the drive thru with the turbo spooled. As a result many turbo models have been well-worn and loosened up thanks to many years and miles of abuse. A nice, relatively underpowered N/A model will typically be alot tighter after many miles simply because they don't produce enough power to do the same kind of damage that a turbo model can produce.
Of course with every pro there is also a con. Your 3SGTE swapped N/A MR2 will still lack the upgraded cooling system and front brakes of the turbo models. In our experiences the N/A MR2's stock cooling system is almost always up the the task of cooling the turbo motor, especially after a coolant flush. The stock brakes are also more than adequate, though an upgrade to twin piston turbo calipers is relatively easy. Finally there is the fuel pump. A stock N/A fuel pump will support stock and slightly upgraded boost levels from a 3SGTE. If you plan on running more than 14-15psi we would recommend an upgrade to a Walbro in-tank fuel pump which will allow to run boost levels far beyond this.