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Fuel Injection from ground zero knowledge.

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    Fuel Injection from ground zero knowledge.

    As if I don't have anything else to do I have decided to go Fuel Injected. There's quite a lot of info on the forum and I have been trolling it for a week or two. I have no prior experience with it but thought that my learning process on this may help others --- this is going to take a while!

    I only want to do this on a standard build engine, no search for ultimate power here but hopefully some gains can be made, if only from eliminating that twisty inlet manifold and eventually an exhaust header will help as well. I decided to go Rover plenum a-la Flying Farmer, as that seemed the easiest and most well trodden route. I will eventually go with a Ford EDIS ignition as I have experience with that when I did the turbo Mini with Megajolt and loved it. So the obvious is to use Magasquirt which pulls them both together. Megasquirt 2 or 3 is yet to be decided, but either way I will use a 36-1 trigger wheel.

    First purchase was a Rover Plenum.. Not many SDI's over here so hopefully a LandRover one will do. So first problem is what are all the pipes for? Which ones will I need?

    Here are some pics...

    1 and 2 look like water pipes.
    3 is one of the many taps into the plenum
    4 is a straight shot into the inlet, maybe for the breather pipes?
    5 looks like it could be used for ignition but it is just after the throttle plate.
    6 is another shot into the inlet but it tees off via adjuster 8 into the plenum which I suspect is an air bypass adjustment.
    7 is another tap into the Plenum
    9 and 10 go into the plenum
    11 looks like a candidate for the brake servo.
    Last edited by trunt; 28th February 2019, 04:30.
    Terry Hunt, Wilmington Delaware

    That is the same plenum I use in my lump which has various outlets, like yours, at different locations.
    On my engine I don't use the heater so I have removed the water assembly which includes water inlet / outlet marked 1 & 2. The plenum heats up enough naturally without its own central heating. If you also opt for removing this there is a hole in the underside of the plenum that you need to plug, otherwise the plenum will draw air and will idle about 2500 rpm. I use a glue plug from a hot glue gun.
    3 / 11 will be a servo take off and one spare for the original application.
    4 is a breather pipe for the engine breathing system.
    5 is a take off from the atmospheric side of the butterfly, presumably for the original distributor. I don't need this so I blocked it off.
    6 connects to 9 and is part of the idle control valve system. Practically, you can avoid using this valve and control idle through the butterfly, however the idle valve also controls the additional air volume required for cold start and warm up and should be controlled through programming in the ECU.
    7 don't know, presumably original application related.
    8 is a blanked plug in my plenum.
    10 should connect to the Rover fuel pressure control valve on the injector fuel rail.

    One thing not shown is the throttle position sensor which fits onto the end of the throttle spindle. These are no longer produced and are rarer than hens teeth, I've seen extortionists want £200 for what they describe as good ones. If you have one keep it safe. A lot of the plenums you see for sale do not have these fitted, they have either been scavenged for use elsewhere or kept by the vendor for separate sale. Mine went tits up and I opted for one from a Rover 45, which cost £7.00 from a scrappy, for which I had to make up a connector which consisted of an M12 bolt cut to length and each end filed down to make a peg at each end to fit the slots in the spindle and sensor. If you have to do this the slots should be filed so that the sensor is fitted with the rheostat slightly open when the sensor is fitted. This ensures that there is an electrical signal which alters immediately the spindle moves.

    In summary, all I use is the servo take off, engine breather, fuel pressure take off and idle air connections. I did have a small take off connected to the breather system for when the butterfly was shut but it screwed up smooth idle so blocked it off.

    You could also consider doing away with the distributor and using your ECU to control coil packs. I use Ford Escort coil packs and my ECU uses the wasted spark and wasted injection system to control the timing of these events, relying on the 36-1 crank wheel. Downside is you need a rolling road to get a correct ignition map, but then you also need a rolling road to map your fuelling anyway.

    Hope this helps and doesn't bore.

    Your wife is right, size matters. 3.9RV8


      Oh you can bore me anytime! Great info, Thanks.

      So I didn't consider the TPS, and yes they are about the same price over here.. I have been looking at the later Lucas TPS which are much cheaper and thinking that It may be adapted by gluing in a short adapter piece, maybe an interim plate to secure it if the screw holes don' t line up. pic below..

      I'll need a water temp sensor but Will I need a MAS and MAP sensor as well?

      OK on the ignition, The EDIS is exactly that, wasted spark 36-1 trigger and uses 2 escort coil packs. I was thinking of initially staying with the dizzy but as this doesn't really have a suitable vacuum advance tap may as well go right there..

      On Mine 8 is a large grub screw that adjusts the airflow through the air tapping from 6 to the plenum, I'm thinking that may become useful.

      Shopping list is getting bigger!
      Attached Files
      Last edited by trunt; 28th February 2019, 13:20.
      Terry Hunt, Wilmington Delaware


        Didn't look into the reason for 8 on my plenum but that makes sense. I'll need to look at it again.

        I use an Emerald ECU on both my Stag and Midget engines and my sensor list consists of the following.
        36-1 crank sensor wheel with a Ford transit flywheel sensor
        Throttle position sensor
        Air temperature sensor
        Water temperature sensor

        The Emerald, obviously, takes the TDC off the crank sensor wheel and uses the TPS position to determine the load position, and between these 2 the engine runs. The air and water temperature sensors are environmental tools which the ECU uses to adjust ignition and injection corrections. The alterations are based on a percentage alteration of the basic fuel and ignition map developed on the rolling road. Once the mapping is done on the rolling road the results are never changed unless I alter something on the engine, The only further work is to achieve good starting and cold running, which I do on a laptop, and consists, of altering the percentages, generally only fueling, between the coldest start and normal running temperature, so it is only tinkering with fueling and idle air control between say 0 and 70 degrees centigrade.

        Megasquirt and others may well use other sensors etc, I have no experience with them.

        The Rover TPS I now use needed only a slight enlargement of the mounting holes to fit my plenum, plus the adaptor I made which I'll try and take a picture of and post on here.


        Your wife is right, size matters. 3.9RV8


          No 8 is useful.
          My Jag throttle body doesn't have one so you have to adjust the idle with a bolt on the throttle stop and this moves the idle position on the ecu map so you have to recalibrate the throttle position every time you move it. The idle screw on yours will weaken or richen the mixture a fraction but not enough to be important.

          When fixing a different throttle potentiometer, make sure there is no play in the linkage or you will never get it to work properly. a lot of throttle pots are spring loaded and this removes any play which is useful.

          You will need to remove the water heated bit as it will not clear the cam cover if you still want the bonnet to shut!

          I don't know how you intend to go from the heads to the bottom of the plenum. As you have probably seen on my various posts it is possible to retain the bottom of the plenum but it is quite a job to get it all sealed up unless you are building in aluminium in which case it is relatively simple to cut out the bottom and replace it with a welded on alloy plate. My 246 bhp Stag uses a steel manifold and I found it was easier to make up a complete plenum bottom. Retain the rover inlet trumpets though, if you do scrap the plenum bottom.

          TV8, efi, fast road cams and home built manifolds. 246bhp 220lbft torque


            OK Neil, This one has both, a throttle stop screw and the air bypass, I'll keep the play of the TPS in mind. Yes I plan to cut the bottom, and use a plate, hopefully you have no patents registered as I plan to copy your every move! One question was how to remove the trumpets, will they pull out? maybe with a bit of heat to expand the alloy, or do you have to cut them?
            I'm probably going to go Aluminium but need to find out the cost of someone to TIG, or there is a decent 200A A/C D/C unit available here for $700 from Eastwood .. but that's a big learning curve - maybe a spool welder then!

            John I have been looking at the Megasquirt2 documents, MAP is on-board and it uses the same TPS, WTS and ATS, there is provision for MAP but its not needed as you say, maybe when I turbocharge it (NO!) I'm going to look at the Emerald now.

            Terry Hunt, Wilmington Delaware




              The penny just dropped..

              So in my pics #6 is piped to #9 to provide filtered bypass air, #10 is the threaded hole for the idle control valve to screw in and the little pipe below 9/10 is the feed to the pressure regulator! So when the bypass valve opens filtered air is sent right into the plenum, raising the speed and the ecu compensates the fuel. (that was my lesson today!)

              Good thing is that its also used on a million Chevy/GMC models so easily found over here.. So what kind of valve is that? (94-95 Discovery) a stepper?

              That only took me an evening or so! SWMBO is getting a bit shirty with me for being "distant" all the time.
              Last edited by trunt; 1st March 2019, 04:39.
              Terry Hunt, Wilmington Delaware



                Attached are pics showing my modified TPS sensor with the adaptor I made up. As Neil advises, the tps needs to be engaged and without play so should be installed so that a slight pre load exists.In the adaptor, the nib into the throttle spindle is angled to ensure this happens. The adaptor also needs to be made so that the length of it isn't too long causing the spindle / tps to lock and drag. If you make one you'll know what I mean.

                If you go to Emerald you can download the software for the K6 ECU which you can look at how your engine would be mapped. You can also download manuals and 'how to' files,all free of charge without signing up for anything. If you wish you can PM me and I'll send you my Rover V8 map which you can load into the programme and play about with.
                Attached Files
                Your wife is right, size matters. 3.9RV8


                  OK all good info.. Looks like your air bypass is slightly different.

                  I have ordered a TPS and will work on sorting that out, also finally have the components I will need in my head and an idea of what each thing does..

                  I'll need:-

                  Water TS
                  Air TS
                  Bypass valve,
                  MAP sensor (maybe onboard the Megasquirt)
                  Wideband 02 and controller.
                  36-1 trigger wheel and sensor +EDIS
                  Fuel pressure regulator
                  injectors and fuel rail
                  High pressure pump and return piping.

                  Did I miss anything?

                  I looked at the Emerald and like it but as I live in the USA Its probably best to stick with the Megasquirt as it uses a lot of locally sourced items and is cheaper, especially with shipping!

                  Terry Hunt, Wilmington Delaware



                    Paul - 3 projects, 1 breaker - garage built and housing 2 white Stags. One runs, one doesn't


                      I am using Megasquirt on 3 cars now. It took ages to get the first one set up but I got a lot quicker with practice!

                      Megasquirt can use either throttle angle from the TPS, or airflow calculated from the on board map sensor, and I believe a combination of the two. I think it is easier to deal with Emerald now than it used to be, it seemed very much a dealer set up only option when I first looked into it and I knew I was going to be fiddling with the engine specifications a lot over the years.

                      The guy who set my cars up on the rolling road is actually an Emerald dealer but has bought a megasquirt unit to use on his Stag. He keeps getting people with megasquirt wanting rolling road set up sessions and now has a separate lap top to use for them as he needed the practice! He certainly knows his way round them now as it was a bit of the blind leading the blind when I took my first Stag to him!

                      He reckons setting up by throttle angle is far simpler as it is a fixed figure. Setting up by airflow varies according to whether the revs are increasing or decreasing and he tends to do 3 or 4 runs for each load setting and takes an average.
                      I could send you a map from one of my Stag engines, the fueling will be well out but the ignition map (certainly on full load) is pretty close to a British spec standard mk2.

                      I am only using a single coil on my engines, and at the moment am still triggering off the lumenition even though I have 36-1 trigger wheels fitted to two of them. Fitting the trigger wheel while the engine was out seemed the best option, it is easier and cheaper to send the megasquirt unit back to be reconfigured for trigger wheel than it would be to replace a knackered lumeniton unit if one fails.

                      TV8, efi, fast road cams and home built manifolds. 246bhp 220lbft torque


                        My bypass is a 4 wire unit from a rover 45 (K series engine), I couldn't get the one that came with the plenum to work properly, so opted for type I am familiar with using.

                        The engine will run without a Lambda sensor, when tuning on a rolling road the sensor is deactivated so it doesn't influence the fueling during tuning. As per usual, the more you tune it and the higher the expertise of the tuner the closer the precision of the fueling and the less need for a wideband sensor so a run of the mill item would do.

                        Good luck with it, I find more fun modifying and tinkering than driving the beast so enjoy.

                        Your wife is right, size matters. 3.9RV8


                          Originally posted by Goldstar View Post
                          I just have to make that!

                          On the megasquirt vs emerald Niel brings up another reason to go megasquirt, more likely to find a rolling road guy with experience on that in the USA.

                          Im actually leaning towards Microsquirt now, itís cheaper ($350) and seems to have all the functionality I will need. It has 2 injector channels and can have 4 ignition triggers so Iím now thinking of using VW 4-post wasted spark coils which it can trigger directly. It cannot do a stepper air valve but there is a module that can be added to do that.

                          More on this later..
                          Last edited by trunt; 1st March 2019, 22:35.
                          Terry Hunt, Wilmington Delaware



                            More on the ECU choices.

                            Microsquirt can do the job but is pushing its limits, i.e max number of injectors on each bank is 4. Also It needs modifications to give 4 Ignition outputs needed for wasted spark to VW coil packs. though I could use EDIS ignition. or stick with the dizzy $388

                            Megasquirt-2 can handle the injectors easily in 2 banks. but still need modifications to run 4 ignition outputs. I could use EDIS/Dizzy here as well $515

                            Megasquirt-3 can handle everything if you add the optional MX-3 board. It could also do semi sequential injection (fire 2 injectors at a time) $762 +shipping

                            Emerald can handle everything as well. including semi sequential injectors. $835 inc shipping

                            Using EDIS is fine, but it means that the ecu does not have any index, i.e. it does not know when its at TDC #1 piston so the injectors are fired regardless, similar I think to Flying Farmers distributor trigger. Not sure how that works as regards the injector timing.

                            I downloaded the sw for Megasquirt and Emerald and must say my initial impression was that the Emerald software was cleaner and easier to understand.

                            Terry Hunt, Wilmington Delaware



                              The triggers for my Emerald are 4 for the injectors and 4 for the coil packs so both injectors and ignition use the 'wasted spark' principle which is what most dealer systems operate under. The hardest part of setting up the Emerald is dialling in the 36-1 crankshaft wheel and to be honest it just about takes longer to connect a Gunsons timing strobe than it does to set the reference angle once you start.
                              There will be enough information available from members on the forum for to create your own basic ignition map and also a reasonable fueling map to get you started without going straight to a rolling road. If you can work a laptop you will be able to create your own basic map on the fly, leaving only final 'polishing' to a rolling road .
                              Emerald has a techy called Karl who is a past master at customer care, no matter how you stuff up he will patiently take you through the fixes, which in my experiences were down to sensor errors / poor earthing or poor terminal connections. I've never had an issue with the ECU that they didn't patiently help me with. The Emerald on my Midget is about 16 years old and is faultless.
                              The hardest part of mapping an ECU is in the cold starting / warm up which in the Emerald is a % adjustment function of the running map. These are not something a rolling road techy would be involved in as it takes days to get right, you may need several days to get starting at 0 degrees C right because the rise in engine temperature affects the variables, so you get it near enough once, then refine it over other colder days, as you do with warm up mixtures. A running engine passes through say 30 degrees c reasonably quickly, so you only have that time to set the adjustment for that point, after that you refine it on subsequent visits, but it throws a curve because the settings either side have an influence. Hey ho, all part of the fun, but manufacturers spend millions programming their ECU's so that the cars are complient in all road conditions from going to the shops to motorway driving. That is why after market chipping produces more power, generally at the expense of smoothness.
                              I am sure that Megasquirt deals with these issues in near enough the same manner, I opted for Emeerald originally because of recomendeation plus a lack of enthusiasm for making up a diy ECU from a parts list.
                              As you have downloaded the Emerald software to look at if you PM me I will send you a running map for a Rover V8 to play with.

                              Your wife is right, size matters. 3.9RV8