BXProject

[jayw]

Does anyone have a cutaway-type diagram of our Bosch injectors?

Also i found this...

The Motronic 4.1 system was used on Opel / Vauxhall eight-valve engines from 1987-1990,[4] and some PSA Peugeot Citroën XU9J-series engines.[5]

The ECU software controls fuel enrichment during cold-start by altering the timing of the main injectors based on engine temperature, no 5th injector is required. The idle speed is also fully controlled by the ECU, including fast-idle during warm-up (no thermo-time switch is required).

The 4.1 system did not include provision for a knock sensor for timing adjustment. The ignition timing and fuel map could be altered to take account of fuels with different octane ratings by connecting a calibrated resistor (taking the form of an "octane coding plug" in the vehicle's wiring loom) to one of the ECU pins, the resistance depending on the octane adjustment required[4]. With no resistor attached the system would default to 98 octane.

The ECU has a single output for the injectors, resulting in all injectors firing simultaneously. The injectors are opened twice for every revolution of the engine, injecting half the required fuel each time.[4]


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How much dofference would this "resistor" make?

[Vanny]

between cock and feck all, they've been sold on eBlag for years with a promise of +17bhp, +17 if the car setup for 90octane fuel maybe (doubtful) but in terms of actual gain, not a lot. You can richen the fuel mixture pretty easily anyways.

[jayw]

I've seen them plugged into the loom on the offside wing but never really paid any attention to it...

Just thought there might be something to be gained if you're running it on Tesco 99 with the green 95 plug in it...

[Bx Bandit]

Don't know, but if it gets rid of my effin knock sensor problem then praise be!

[docchevron132]

you'd have to change to a proper ECU then Bandit...

I wasn't aware of the resistor thing, not that I'm too fussed, since my cars only ever run on 99RON.
But, with fuel proces going the way the are, maybe resistorising it for 95RON could be a bonus... hmmm.

[mat_the_cat]

You could have a switch between no resistor and the 95 RON resistor on the dash?

[Bx Bandit]

I might do that Doc, one day, when the moon has dissolved and the sun is a 60watt blub!

[jayw]

So, returning to topic....

No-one got a schematic / cutaway of an injector?

[Vanny]

Pretty sure there is one in the Bosch blue book. I've deffinatley seen one, so try Google

[Bx Bandit]

So, returning to topic....

No-one got a schematic / cutaway of an injector?

Don't you ever..............EVER return a thread back on topic

[Vanny]

oi lazy git,



that took all of ONE google search, and the first result no less.


http://www.northamptonmotorsport.com/default.asp?id=95

[Bx Bandit]

Yeah........................!







Bitch!

[docchevron132]

Looks suspiciousley like an injector cut away to me...

[Bx Bandit]

I know I'm being typically dull here, but, quoting him from Barsingstark:

"The ECU has a single output for the injectors, resulting in all injectors firing simultaneously. The injectors are opened twice for every revolution of the engine, injecting half the required fuel each time.[4]"

How the fuck does the engine get the right amount of fuel in the right cylinder at the right time and what happens to the fuel not used? I thought I knew this when I read up on injection when I got the valver, but now it makes less sense than I remember!

[jayw]

that took all of ONE google search, and the first result no less.

I tried that and gave up after 10 minutes with no joy

quoting him from Barsingstark:

Don't knock it, Basingstoke comes highly recommended by the Drift boys, Freerunners, Tarmac PLC and Criminals... With backing like that you can't go wrong...

How the fuck does the engine get the right amount of fuel in the right cylinder at the right time and what happens to the fuel not used? I thought I knew this when I read up on injection when I got the valver, but now it makes less sense than I remember!

Part ComSen, part speculation (the ratio is dependent on how much i get corrected )...

Injecting twice would allow more accuracy of fuel quantity (using hopper theory). I'd assume during 3rd/4th stroke, once on the down and once on the up stroke. Would also assist with improved vaporisation..

The only problem with that theory is that whilst cylinders are on strokes 3/4, the one(s) on stroke 1/2 would be getting fuel, which (particularly on the exhaust stroke) is a no no....???

So, either that info that i pasted from Wiki is wrong or I understand it about as well as you do Bandit me old luvver...

[Bx Bandit]

Part ComSen, part speculation (the ratio is dependent on how much i get corrected )...

Ooh i wasn't having a go at you me old tater, just trying to figure it out!

[jayw]

Part ComSen, part speculation (the ratio is dependent on how much i get corrected )...

Ooh i wasn't having a go at you me old tater, just trying to figure it out!

I never wrote the original post, it were copied from Wiki-tater...

I not figure it out much neither.. is that neither or niether, can't decide which looks right... 'I' before 'E' except after 'C' would suggest niether, but neither looks better... awwwww fuck knows, i give up, i'm off ta boil ma heed in a pat o pish...

[Vanny]

You NEED to get the Bosch blue book for this one;

ISBN 1-86058-474-8
Bosch Automotive Handbook

It details EVERY product Bosch GmBH have made for the automotive industry, generally starting with basic theory then applying it to BOSCH systems, it includes all versions on Motronic too. It also partly helped me get the job i have, and i try to never be more than 10 minutes away from a copy. Sod Wiki, get the Bosch Blue book - oh and have a laugh at the list of authors, its like a list of all the professors in Germany!

[Way2go]

How the fuck does the engine get the right amount of fuel in the right cylinder at the right time and what happens to the fuel not used? I thought I knew this when I read up on injection when I got the valver, but now it makes less sense than I remember!

Because it's injected before the inlet valve, the fuel is not wasted because it lingers until the valve opens at the appropriate time. The "right amount" of fuel is therefore calculated over the 4 strokes. The spray pattern and duty cycle from the injectors is also varied by the ECU dependant on your driving conditions, speed/demand etc.

[Bx Bandit]

Where does it 'linger' then? Surely, the idea of injection is to inject an atomised quantity of fuel hence the pressure bar etc. But I would expect it to 'splurge' in if it has to linger about somewhere!

Vanny, does that blue book detail any diesel (i.e. Boch VE pump) stuff me old teapot?