Previously we discussed the all new MIVEC Engine of Mitsubishi. Today we will be resuming the next versions of MIVEC engines namely
1. MIVEC DOHC 16-valve Engine (4B1)
2. MIVEC DOHC-12valve Engine (3A9, 3B2)
As we know Mitsubishi Innovative Valve timing Electronic Control system (MIVEC) is the brand name of a variable valve timing (VVT) engine technology developed by Mitsubishi Motors.
Dual Over Head Cam (DOHC)
In the above picture, you can see there are two separate cam shafts riding atop the head. For DOHC heads, the cams can be tied together with a short chain, then have a separate chain/belt which drives the cams, or can have just a single chain/belt which runs the whole thing. DOHC engines usually have a configuration of 2-intake and 2-exhaust valves per cylinder uses a five valve per cylinder (3-intake and 2 exhausts). In most cases, the cam directly actuates the valve without the use of a rocker arm.
MIVEC DOHC 16-valve Engine (4B1)
All engines developed within this family have aluminum cylinder block and head, four valves per cylinder, double overhead camshaft layouts, and MIVEC continuous variable valve timing. All variations of 4B1 engine share the same short block. The difference in displacement is achieved by variance in bore and stroke.
The 4B1 engine family is the first to have the continuously variable valve timing MIVEC system applied not only to its intake valves but also to its exhaust valves. The intake and exhaust cam timing is continuously independently controlled and provide four optimized engine operating modes.
The 4B1 MIVEC engine series used in the Outlander, as well as the Japanese-market Delica D:5 and Galant Fortis models, uses the continuously variable intake and exhaust valve timing MIVEC system that continuously and optimally controls the intake and exhaust valve timing according to engine running conditions. This system delivers high performance and fuel efficiency.
Continuously controlling the intake cam and exhaust cams independently, this system provides a combination of maximum power output, high fuel efficiency, and a high level of environmental performance by making possible more precise valve control according to RPM and engine load than intake-only systems.
MIVEC DOHC-12valve Engine (3A9, 3B2)
MIVEC DOHC-12valve Engine 3A9
The Mitsubishi 3A9 engine is a range of all-alloy three-cylinder engines from Mitsubishi Motors that were jointly developed with 4A9 engine family. They were introduced in the 2003 version of their Mitsubishi Colt supermini, and built by DaimlerChrysler-owned MDC Power in Germany (previously a joint venture). Cool Right..!
MIVEC DOHC-12valve Engine 3B2
The Mitsubishi 3B2 engine is a family of all-alloy three cylinder engines developed by Mitsubishi Motors. The preliminary version of the 659 cc engine was first seen in the “i” Concept test car introduced in 2003 and used Mitsubishi’s Smart Idling system which turns off the engine automatically when the vehicle is stationary and can restart it within 0.2 seconds. So equipped, Mitsubishi claimed the prototype was capable of fulfilling the “three liter initiative” for gasoline engines, meaning fuel consumption of no more than 3.0 liters per 100 kilometers (94.2 mpg, 78.4 U.S. mpg). Can You Imagine..!!
The MIVEC engine used in “Mirage” model uses the continuously variable intake valve timing MIVEC system that continuously and optimally controls the intake valve timing according to engine running conditions. This system delivers high performance and low fuel consumption.