Team-BHP - CNG questions

CNG kits can be installed on Diesel engines, however the costs involved are high and, No longer a Dual fuel advantage can be retained.

The procedure involves, creating Bores in the Head, with Injection systems for Individual Gas delivery.

Unlike in the coventional Petrol, where the Mix is created in the Throttle-Intake Manifold.

At the same costs of Retrofitting a diesel engine, you can get a 5th generation ECU Sequential Injection system for Petrol.

Quote:

Originally Posted by dr.abhijeet (Post 644362)

OT:i dont think any astra was carb. the ist engine (1996) and 2nd engine 1997(16NZR..IIRC) were both single point fuel injection.
I may be wrong though. can someone confirm

It is called a Throttle-body injection system. It injects fuel at the throttle body (same place where the venturi in a carb would have sucked petrol).
Cheap alternative for MPFI. Uses same aircleaner, intake manifold, etc. as a carbureted engine.

To add Throttle Body injection systems are the most common and are known as the 2-4th Generation Systems.

The latest are Sequential Injection systems- which run similarily to the MPFI system in most petrol cars.

Mapped along with a Seprate ECU, they bypass the Throttle and inject the Lean mix into the Intake Manifold individually.

Expensive system, but really worth.

Quote:

Originally Posted by wolfinstein (Post 830215)

CNG kits can be installed on Diesel engines, however the costs involved are high and, No longer a Dual fuel advantage can be retained.

Is there a considerable diiference in the performance of a Petrol Engine fitted with a CNG kit and a Diesel Engine fitted with a CNG Kit?

basically diesel ignites by compression, petrol by spark. so enough changes needed to make it fit for CNG - so my limited knowledge. people happiest those who started on CNG itself!

hi wolf thanks for the reply
so that means only sequential kits can be installed on diesel cars, ones which comes with separate ecu??
would'nt that ensure no loss of power in pickup while in cng mode.

A diesel engine involves direct bore drilled into the Piston Chambers, with mods to the Spark ignition system.

Sequential Injection system needs inject points into the Intake Manifold.

With a Diesel engine, the cost is not worth it, plus its much too complicated to get done in India without a good retrofitter- Primarily this system is incorporated with Buses in Delhi that too Old generation ones, the newer ones have a Direct CNG injection system inplace.

You rather let a Diesel remain a Diesel, CNG is best for Petrol Engines.