Multipoint injection vs direct injection

[oddkid82]

Hey guys my friend is currently looking at getting a patrol. Do any of you guys know anything about the differences of the multipoint injection and direct injection motors. Have heard stories that on is no good but I can't remember which one?

 

[happy john]

multi point refers to say a 4ltr falcon before that it was throttle body injection in diesel terms direct injection is used in navara's patrols with zd30 also tritons ect

 

[bods]

Multi point injection just means there is one injector for each cylinder.

If you mean diesel there is direct injection and indirect injection. The mq patrol diesels were indirect injection, but I'm pretty sure the 4.2 and 2.8 diesels from gq onwards were all direct injection. There's not really "one that is no good" its more that direct injection makes more power and is more efficient. Basically the difference between them is indirect injection has a swirl chamber, or precombustion chamber.

This should help a bit http://en.wikipedia.org/wiki/Indirect_injection

 

[Old.Tony]

So-called "Multi point fuel injection" systems are accurately named but somewhat confusing.

In the beginning, God created the carburettor and saw that it was good. Fuel was delivered to the intake manifold, metered by a butterfly valve allowing more airflow and suction drawing the fuel out of the carby's fuel float. Fuel atomisation was minimal, and the mixture in the airstream was not perfect.

Fuel injectors turned things around. Fuel was pumped through a fine nozzle into the intake manifold that led to the cylinders. This is "single point fuel injection".

Efficiency was further improved when they placed a fuel injector just outside of each intake valve - this is "multi point fuel injection".

They then developed an injector that could withstand the temperature and pressure of combustion, and positioned the injector directly in the top of the combustion chamber - this is "direct injection".

 

[happy john]

spot on again tony bugger the computer that controls it all