10 11

HR/MR EngineTechnology Overview

FIP FIP

Conventional engine HR/MR engine

High-adhesion FIP gasket and chamfer shape

Pulleys are in a single plane

Coolant pipe built into cylinder block

Cracking-processed connecting rod and cross-sectionsCracking-processed connecting rod and cross-sectionsCracking-processed connecting rod and cross-sections

Fewer parts for lighter weight and enhanced reliability

The HR/MR engines employ a range of innovative technologies for downsizing and weight reduction that are essential to improved fuel economy. We reduced the number of parts by approximately 20% compared with the previous engine design, thereby enhancing reliability and manufacturing productivity.

Coolant pipes built in

Cracking-processed connecting rods

These integrally cast con rods offer lighter weight than conventional con rods, which are constructed in two parts, separated at the eye where they join the crankshaft. The cracking processed con rod is manufactured in one piece, then the lower connecting rod eye is broken in two (the crack-ing process) and, fi nally, the two parts are rejoined after mounting. Mating of the uneven surfaces created by the cracking process results in a very precise joint.

The coolant distribution system has been thor-oughly redesigned in all areas, incorporating it into the block and head. Pipe-free construction mini-mizes dependence on external couplings, thereby decreasing the number of parts and contributing to weight reduction.

Serpentine auxiliary drive

High-adhesion FIP gasket and chamfer shape

The HR/MR engines use a single-belt ser-pentine auxiliary drive system to drive the air conditioner compressor, power steering pump, alternator and other components from the engine. Whereas conventional engines run each auxiliary component separately, this system puts the pulleys in a single plane, thereby shrinking engine length. Use of auto-tensioners reduces belt load and extends service life.

“Form in place” (FIP) gaskets are used to improve cylinder head and oil pan sealing. These create a sealant layer of uniform thickness to improve reliability against oil leakage within the engine. In addition, we adopted a chamfer process to shape mating surfaces based upon fl uid dynamics. Sur-plus gasket material protruding from the mating surfaces fi lls the chamfer to improve adhesion.

10 11

HR/MR EngineTechnology Overview

FIP FIP

Conventional engine HR/MR engine

High-adhesion FIP gasket and chamfer shape

Pulleys are in a single plane

Coolant pipe built into cylinder block

Cracking-processed connecting rod and cross-sectionsCracking-processed connecting rod and cross-sectionsCracking-processed connecting rod and cross-sections

Fewer parts for lighter weight and enhanced reliability

The HR/MR engines employ a range of innovative technologies for downsizing and weight reduction that are essential to improved fuel economy. We reduced the number of parts by approximately 20% compared with the previous engine design, thereby enhancing reliability and manufacturing productivity.

Coolant pipes built in

Cracking-processed connecting rods

These integrally cast con rods offer lighter weight than conventional con rods, which are constructed in two parts, separated at the eye where they join the crankshaft. The cracking processed con rod is manufactured in one piece, then the lower connecting rod eye is broken in two (the crack-ing process) and, fi nally, the two parts are rejoined after mounting. Mating of the uneven surfaces created by the cracking process results in a very precise joint.

The coolant distribution system has been thor-oughly redesigned in all areas, incorporating it into the block and head. Pipe-free construction mini-mizes dependence on external couplings, thereby decreasing the number of parts and contributing to weight reduction.

Serpentine auxiliary drive

High-adhesion FIP gasket and chamfer shape

The HR/MR engines use a single-belt ser-pentine auxiliary drive system to drive the air conditioner compressor, power steering pump, alternator and other components from the engine. Whereas conventional engines run each auxiliary component separately, this system puts the pulleys in a single plane, thereby shrinking engine length. Use of auto-tensioners reduces belt load and extends service life.

“Form in place” (FIP) gaskets are used to improve cylinder head and oil pan sealing. These create a sealant layer of uniform thickness to improve reliability against oil leakage within the engine. In addition, we adopted a chamfer process to shape mating surfaces based upon fl uid dynamics. Sur-plus gasket material protruding from the mating surfaces fi lls the chamfer to improve adhesion.