Itinerant Air-Cooled

I hope to do the volume test this weekend. I have two pumps, and I'll try both of them and post the results.

Reid wrote:Maybe a water cooled Vanagon had bank fired injectors instead of our batch fired injectors? The engineers could have been trying to minimize a pulse on the other bank, I guess.

I'm unable to determine from a brief perusal of Bentley whether that is the case or not. There doesn't appear to be any input to the ECU which would inform it which bank is ready to fire (ie. camshaft position sensor or distributor-driven trigger), so my gut feeling is that they still used a batch-fire scheme. Anyone with a WBX know for sure?

"two pulses occur for each working cycle regardless of the number of cyclinders. For each turn of the crankshaft,each injection valve injects once, regardless of the position of the intake valves "

dingo wrote:"two pulses occur for each working cycle regardless of the number of cylinders. For each turn of the crankshaft,each injection valve injects once, regardless of the position of the intake valves "

Where did you get that quote?

I am of the mind that Digifant is a "simultaneous single fire" with half quantity per pulse.
Colin (corrected -just now)

They are fired together. I just looked at a wiring diagram.

Gasoline Fuel-Injected System L-Jetronic

(Robert Bosch GmbH Stuttgart 1995)

..very good reading and great diagrams and charts

Reid wrote:They are fired together. I just looked at a wiring diagram.

Within the L-Jetronic operation all 4 injectors open and close at the same time. All 4 injectors are opened and closed twice every 720 degrees; or 1 full engine cycle -- 4 strokes. The signal to open the injectors is triggered by falling edge from the negative side of coil



and then signal goes through a process to be shaped, divided and to calculate the exact opening interval based on auxiliary inputs: TSII, TSI, AFM. These 3 inputs will "append" additional time to the base injector open time.

Another interesting read is the L-Jetronic patent:
http://www.google.com/patents/US4481928 ... ms&f=false

luftvagon wrote:
Another interesting read is the L-Jetronic patent:
http://www.google.com/patents/US4481928 ... ms&f=false

Oh my, yes. Especially the bit about calculating the "sucking-off coefficient". Who sez that Toyotas aren't sexy?

SlowLane wrote:

luftvagon wrote:
Another interesting read is the L-Jetronic patent:
http://www.google.com/patents/US4481928 ... ms&f=false

Oh my, yes. Especially the bit about calculating the "sucking-off coefficient". Who sez that Toyotas aren't sexy?

Toyotas!
L-Jetronic was All German in the beginning, didn't Nippondenso sort of imitate Bosch to the point that they just bought rights to re-brand?
Colin

Amskeptic wrote:

SlowLane wrote:
Oh my, yes. Especially the bit about calculating the "sucking-off coefficient". Who sez that Toyotas aren't sexy?

Toyotas!
L-Jetronic was All German in the beginning, didn't Nippondenso sort of imitate Bosch to the point that they just bought rights to re-brand?

Could be. The Toyota patent referred to by luftvagen's link clearly shows that they were trying to put their own personal mark on the "L-Jetronic style" of fuel injection, in this case by smoothing out the effects of AFM vane overshoot during sharp acceleration.

I bet that Bosch didn't mind by then, because they would already have been well into development of the hot-wire MAF sensor which eventually supplanted the AFM. As far as they were concerned, Toyota et. al. could dick around with workarounds for the AFM all they wanted, while still paying Bosch the licensing fees for it.

SlowLane wrote:
The Toyota patent referred to by luftvagen's link clearly shows that they were trying to put their own personal mark on the "L-Jetronic style" of fuel injection, in this case by smoothing out the effects of AFM vane overshoot during sharp acceleration.

Seeing as the vane overshoot is the "accelerator pump", no wonder the pig BMW 630CSi could spank a Datsun 280Z.
Colin