The 7MGTE engine on the Toyota Supra is a long-lasting, well-engineered piece of machinery that provides ample power and reliability to a celebrated sports car. Unfortunately, the 7MGTE suffered one flaw from the factory: faulty head bolt pressure. You must follow the correct Supra head torque specs to avoid a blown head-gasket on your vehicle.
A third-generation Toyota Supra built at a Toyota factory used a composite head gasket tightened to approximately 58 foot-pounds of torque. Though this is still the factory suggested torque for head bolts on the Toyota Supra 7MGTE engine, the torque is not adequate and results in head gasket failure. The bolts on the Toyota's cylinder head, after the rigors of everyday driving, would stretch, providing an improper seal on the engine block.
Through trial and error over the Toyota Supra's 25-year history, the suggested torque for the 7MGTE cylinder head has been increased to a range of 65 to 82 foot-pounds of torque. The use of an aftermarket metal head gasket for the Supra might allow you to torque the head bolts to the highest end of this range. The higher torque levels are necessary to prevent head-gasket failure in the future. If your 7MGTE engine operates long enough with a blown head gasket, you might warp the cylinder head or block of the motor.
After installing a new head gasket on your Toyota Supra, double check the tightness of the head bolts after driving the vehicle approximately 620 miles. The bolts should be re-torqued to between 70 and 75 foot-pounds. The heat and stress placed on the cylinder head and engine block during daily driving might work the head bolts loose. Head bolts should always be re-tightened in the factory-specified sequence.
