Understanding Engine brake

[Flytox]

Bonjour à tous

On my R19 Diesel, there is a Lucas Cav injection pump which has no electronics (1992) and, it seems, it does not process the depression information in the intake.

I have decked it out with a butterfly in the intake duct like a gasoline engine with carburetor and keeps it in almost closed position. Now I see a loss of engine brake when I take my foot off the accelerator.

What is the link between these 2 phenomena (throttle / engine brake), pumping losses have decreased ???
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[Other]

Hello

What is the link between these 2 phenomena (throttle / engine brake), pumping losses have decreased ???

A badly designed engine or one which has a diagram, valve opening angle poorly studied, has a higher engine brake
multi-valve and well-designed engines have little engine brake
manufacturers seek as little as possible (water hammer) and rolling gases through the engine.

In a diesel, at idle or lowering driven on compression, the downstream engine a large amount of air for a drop of diesel fuel injected when it is not Zero injection, on certain engine, therefore the compression effort, does not not return as a spring. At the end of the compression, part of the heat generated by the compression 600c crosses the culase to go to the LDR in pure loss.

The remark which one can make with a doping with water is that the output is better when the engine receives an injection which is close to the limit of the available air (full load in power when the engine is normally on the point of smoking) it is for this reason, that several (fitter) of water doping tries to reduce the admission, to the intermediate regimes. The other reason is to have more vacuum in the reactor, somehow forcing the engine to suck in the reactor.
but that has limits, when the power drops if we try to get everything through the reactor it cools and consumes too much water to be effective.
Before theorists say it, and we know it ..
Normally in an engine it is inappropriate to restrict admission, it is against common sense, but for a water doping to work, there are certain compromises that you have to know how to dose if you want get the most out of it.
The challenge is to operate at its best, water doping at low speeds in the usual speeds of the car.

Andre

[Flytox]

Hello André

I need to find a method to objectively compare the deceleration by the engine brake, like arriving at constant speed on a road, release the accelerator in the same place (easy to say) and measure the distance to reach 20 km / h for example. By repeating the measurement several times we should have a more objective measurement.

The noise from the car has changed enough to disturb my appreciation ... I need objective data.
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