Fuel Injected fun...

It'll run well enough, although I'm not sure if the map will have enough adjustment in its settings to deal with the smaller cylinder capacity.

In theory it bases fuel injection timings on the amount of air going in, throttle position, along with fuel and engine temperature, opening the injectors long enough to deliver the appropriate amount of fuel required to maintain the optimum stoichiometric ratio.

Wether or not it's sensitive enough to work out its running a 3.5 or a 3.9 I couldn't tell, although the lambda sensors will help give it a bit more of a clue as to if it's over fuelling or not.

My old boss once had an argument with me on a similar subject when we replaced a 1.4 K Series in a Rover 25 with a 1.8 lump, he was adamant that the ECU would compensate for the extra capacity.
The response that he'd been doing the job 30 years so he should know when asked why the ECU's were different part numbers if things were the same didn't really cut it with me.

As mentioned, it's worth taking the opportunity to have a chat with Mark Adams. I'm fairly clued up, he is THE authority.
 
Long as is runs well enough to start my project then that's OK. I'm ultimately looking at some kind of custom map anyway. I've programmed EEPROMS before. I'd be interested in reverse engineering the originals anyway. I'm willing to bet the granularity and number of data points isn't that high anyway and that not all the inputs shift the map, they merely apply a programmed correction to the basic map. So it won't be a very "dimensional".

I'm guess relative difference between 3.5/3.9 is far less of an issue than 1.4/1.8 by relative size and the degree of sophistication and more accurate control of the later system.
 
I myself cant see fixed map programming as being that good as they only tend to look at a small amount of fixed points and a couple of moving parameters.
Some thing like the 14CUX with multiple loops and sensors looks more adaptable to varying load and driving conditions whilst maintaining best economy and power.

I too have programmed eproms and written code but I really cant be shagged even for self satisfaction, if some one else has already done a good or as seem to be in this case an industry leading job then I am all for taking the back seat and just enjoy the ride ( the P6 ride :LOL: )


Graeme
 
Well I don't want to go too far into megasquirt territory either, just my own curiosity. It's going to be what 4 or 8k tops considering the Tornado fighter/bomber remains airbourne on 64k... Shouldn't take more than a day to disassemble and analyze.

Actually considering the likes of Tornado (the car engine one) chips sell for £500 after the initial rolling road work and basic programming, this seems like easy money to me... No wonder they talk of a scrambling chip to prevent copying (not sure how that can actually be on such a simple system).

I believe some of the inputs are even "binary" anyway like the fuel temp sensor is hot or cold and the speed sensor determines whether you are above/below a speed to avoid stalling.

So you have throttle angle, engine speed, air mass/volume and the O2 as your 4 basic parameters. Could be as simple as a single RPM map for each tune resistor and the rest are programmed adjustments.
 
Yes it does all seem a bit simplistic, I guess you could pull in ignition advance curves and any other known parameter variables to make the performance more lively or other preset drive styles.
As you say money for jam, a lot of the product I designed and manufactured in the past were those associated with after market car engine management performance electronics, there really is no rocket science in any of it :LOL:

Graeme
 
Great thread, I've been thinking on this for awhile now; and the Megasquirt / 14CUX issue is still a choice to be made so it'll be interesting to hear how the owners get on.
Personally in preparation for fuel injecting our old girl, I obtained a donor setup from a 99 Thor engined Range Rover. Obviously the Motronic can't be used as its tied into too much of the donors electronics - but as far as I know the Megasquirt just needs to 'see', sensors and the like to drive them ( oversimplification I know but you get the picture).
A set of Late Range Rover heads takes care of the 'unleaded ' situation and whether we keep the 3.5 or opt for a 3.9, composite gaskets (these are available for the 3.5 - you can't use later gaskets due to circumference difference). should make sure that the compression stays sensible.
Good sources of information on this and other systems can be had on the V8 Forum, and British V8 website.
Good Luck and please keep us informed.
 
I have almost everything needed now for this conversion to 14cux. Some notes I have read indicate a need to tell the ecu some items are not present, by grounding their leads through a resistor - eg AC load, front screen heater. Also to ground pin 34 through 510 Ohms to indicate manual gearbox. How to fool the road speed input (pin 6)?
thanks
 
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Does it need to be pulled up? It's not selecting anything - it's a speedometer input. The road speed signal does two things. It switches between low and speed idle (at 3mph I believe) and it implements the 112mph limited which is needed for off-roaders on all seasons tyres. Both of which are not really needed.

This is an old thread. I'm no further than before... :)
 
The loom I have does not have pins 30 & 38 present. This means I cant connect a Rovergauge to it. Anybody know which lead of these 2 connects to which wire on a Rovergauge cable please?
Or is it pins 9 and 18 that are relevant? The page on Rovergauge shows a white socket & plug with wire colours that match what I have, and they use pins 9 & 18.
14CUX - cmb

Edit - more queries. Have pinned out and labelled almost all the connections. But then I find 2 fly leads (~10" long) of red and black wires, sheathed, ending in insulated female spades - look original. The red wires go back to pins 11 and 13 in the connector hood - power supply to L and R injectors. Cant find the other end of the black wires. Also when I try to get connection from pins 11 or 13 to the injectors, all of them show open circuit. I can trace the injector brn/or wires to the main relay, which makes sense. The power lines to injectors are shown as going direct to pins 11 and 13, no relay involved.
????

Solved - these leads are spliced into the injector feeds from pins 11 & 13 , probably to enable looking at the pulses. If I interconnect the red-black sockets I get continuity to 11 & 13 from 2, (with an injector fitted) so all OK. Just need to retape the loom with good tape.
 
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Still doing long range plans for efi.... I have Rovergauge software and a cable. Anybody know if it would be useful to connect it to my loom, and apply 12V at the relevant points? I have an EFI manifold on hand that I could connect the loom to. For those who have done this, where did you mount the part of the loom that lived inside the cabin of a RR or Disco? Not a lot of spare space in the P6.
 
For those who have done this, where did you mount the part of the loom that lived inside the cabin of a RR or Disco? Not a lot of spare space in the P6.

I have installed a hotwire system, but used megasquirt and made my own loom, so it fits where it should. Could you modify it so it fits the P6?
 
I have installed a hotwire system, but used megasquirt and made my own loom, so it fits where it should. Could you modify it so it fits the P6?
The 14CUX ain't exactly big. I'm not sure what the problem is. If it didn't fit on the A-pillar then it could certainly fit in the drivers glovebox or possibly under the seat. Or under a metal cover in the passenger footwell. Most likely up underneath the dashboard under the glovebox where the footwell vents are - I also have my Dakota Digital speedo driver here. I have the complete system including the loom in the basement. The biggest challenge is almost certainly shortening the cables.. You'd never get the connector through any existing hole in the firewall anyway, so it'd need cutting.
 
This is all long term thinking stuff. Well....I guess replacing the plastic spacer in the passenger footwell with a piece of ply will give me quite a bit of room. Will take a pic of the loom I have from the firewall grommet onwards. The ECU itself should be manageable. Are there any pics of swirl pots under the car on here anywhere please? Any thoughts on powering the loom (connected to a manifold), and trying Rovergauge?
 
The knock sensors work with the ignition system so you should be ok till you start working on that.
There is a book, currently inaccessable to me, by an english tuning shop which goes into the EFI systems in detail with specific reference to non-factory setups. Its available online. Somewhere.... I'm off to look for it..
 
Found it:
Tuning and Modifying the Rover V8 Engine
by the lloyd brothers
Crowood press - very reasonably priced by them.
 
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My loom from the firewall grommet...
3kQmLXf.jpg
 
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