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Continued woes.

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  • Continued woes.

    As my grandmother used to say when she lost in cards:
    Shit, Piss and Corruption!

    A friend and I did some mapping today just to realise that the fuel pump is indeed maxing out, even with a MAP sensing pressure regulator.

    I maxed out the pressure at 53.2 PSI. The pressure is nice and stable until about 6500 RPM. After that the pressure drops to 47 PSI, and the injectors go permanently on since we try to compensate for the lower pressure with longer duty cycle.

    I have now installed a rev limiter at 6700 RPM.

    I now have two alternatives.

    1. Get an aftermarket injection system fuel pump and put it inline with the stock unit.

    2. Get a new unit from Caterham and install it in the tank.

    I'll call Caterham Monday and to check out what they have in stock.

    Any advice is greatly appreciated.

    /Magnus F.

  • #2
    Unfortunately I don't know much about injected engines...but a dumb question: Isn't the fuel pump more or less generic? Then you could get one for cheap for a bigger 6 or 8 cylinder engine and have more fuel than you will ever need for your Zetec? E.g. a Mustang pump is $130 or even less from the wrecker. But what do I know....

    Gert

    Comment


    • #3
      As far as I know, they are generic, but are often submerged into the tank with specific fittings.

      I am looking at an MSD pump (http://www.msdignition.com/fuel_7.htm), that seems to be what I am looking for.

      If it gets fed pressurised fuel by the stock pump (in the tank), it should be able to add pressure on top of that, giving ample of pressure and flow for the high boost area of the map.

      I'll try to track one down tomorrow.

      /Magnus F.

      Comment


      • #4
        New pump aquired. As soon as I have burned off some gas, I will remove the old pump to check if I can replace it with this one.

        Comment


        • #5
          Ok.

          A full day's work resulted in the following:

          The old pump, which was submgerged into the tank was replaced by a piece of tubing going from the tank cover to the sock doing basic filtering and fuel sucking. I removed the stock fuel pump wiring and tucked everything away so that I can re-install the original pump in the future.

          A note on the fuel pump removal procedure. The tank has to be loosened from its frame in order to move it sideways enough to get the pump out. However, if anyone else are thinking about ditching the stock pump, there is a trick that lets you keep the tank in place and still get the pump out:

          1. Jack up the rear of the car and remove the right rear wheel.

          2. Remove all philips head screws from the tank cover holding the pump (on the right side of the tank).

          3. Remove the fuel hose attached to the tank cover. (You will need new copper/aluminum washers here.)

          4. Pull the pump out as far as possible.

          5. You will now see two small bolts (7mm head?) on each side of the bracket holding the actual pump. Unscrew these.

          6. You will now be able to separate the tank cover and it's integrated pipe from the pump assembly and remove the pump separately.

          Don't drop anythning into the tank.

          I reused the fiber washers for the philps screws as well as the tank cover seal itself with no leaks. I don't know if everyone will be successful in this.

          Don't overtighten the screws since it will warp the tank cover seal, leading to leaks.

          --

          A new pump, that was specced for Atlantic series cars a few years back, was installed beside the stock fuel filter on the firewall forward of the de-dion tube.

          Once I'd figured everything out, I could reuse much of the original plumbing and get the pump in a position so that it will always have fuel, even when turned off. (Most fuel pumps don't like running dry since the fuel also doubles as a lubricant). My guess is that any in line pump with sufficient capacity can be used in this installation.

          Pictures at http://www.californiacaterhamclub.co...t.php?cat_id=3
          (The electrical installation will be cleaned up.)

          The new pump can reach a higher pressure than the old one. When I fired up the car, I immediately got 57 PSI where the old one maxed out at 52.3.
          I've driven the car for about an hour, and it seems OK.

          Some minor remapping has to be done, but I need help with that since mapping a car while driving it is quite suicidal. Also my wideband lambda probe is acting strangely, so I haven't stressed the pump yet with high boost/high RPM since I don't want to risk leaning out.

          /Magnus F.

          Comment


          • #6
            Mapping done!

            I forced my poor wife to don a helmet and drive up and down the 73 while I was hacking away at the laptop in the passenger seat.

            The fuel pump is keeping the pressure steady at 60 PSI all the way up to 7500 RPM.

            Chris: I may just be able to hand you your ass speedwise. I was running very, very rich at .80-.82 (with stoichiometric at 1.00) when we were up in the mountains. I am now doing .89-.90 over the entire board (except on overrun), which is where things should be.

            I'll do an oil change and top off the gearbox oil before I leave for the streets Friday.

            /Magnus F.
            Last edited by magnusfeuer; March 3, 2013, 01:50 PM.

            Comment


            • #7
              Congratulations! See there is nothing an electrical engineer cannot fix :mrgreen:

              I will see that I get bigger venturis installed for my carbs to keep up :? same problem 0.8 lambda but different solution....

              Gert

              Comment


              • #8
                Chris: I may just be able to hand you your ass speedwise. I was running very, very rich at .80-.82 (with stoichiometric at 1.00) when we were up in the mountains. I am now doing .89-.90 over the entire board (except on overrun), which is where things should be.
                Geez. I guess I'll have to find something to take off of the car. Those light weight Dedion ears just won't be enough. Maybe if I cut out some of those frame rails that don't look like they're doing anything...
                Chris
                ------------
                A day you don't go a hundred is a day wasted

                Comment


                • #9
                  Don't worry Chris,

                  but I am not going to post the weight difference between your and Magnus' car here..... :roll: top secret 8)

                  Gert

                  Comment


                  • #10
                    I can only agree to my overweight at 1600+ lbs with me and a full tank of gas in the car. Chris was about 200 lbs lighter in his car, if I remember correctly.

                    Gert, can you mail me the spreadsheet plz!

                    The SV is 50 lbs heavier than a standard De Dion, and Chris has a superlight, I believe, which is approx 200 lbs lighter than mine (1080 lbs).

                    The main weight difference, as far as I know are:

                    Wheels.
                    My 15" prisoners with VictoRacers V700 weigh in at around 35lbs each with tires. Chris ran 13" lightweights with ACB 10s.

                    Supercharger.
                    Somewhere around 35 lbs additional weight.

                    Exhaust system.
                    I don't know the weight of this, but it is HEAVY.

                    Me.
                    I weigh in at 205 lbs (this morning). My guess is that Chris is a good deal below this.

                    Zetec
                    My Zetec, even without the supercharger, is 20-30 lbs heavier than the Duratec, if I remember correctly. This is mostly due to the Zetec's cast iron crank case.


                    Now that I am happy with the power output of my car, I'll start operation weight loss:

                    13" wheels with light tires. I'll use Brad's experience here.

                    Lighter exhaust system with sidepipe and no catalytic converter.

                    Lighter me. I should be able to shed 10 lbs with a bit of work.

                    I already have a lightened flywheel.

                    In the long run, I may build myself a naturally aspirated Duratec engine, just for the experience.

                    Any other suggestions?

                    /Magnus F.

                    Comment


                    • #11
                      lighten up

                      Hi Magnus,

                      Using the aeroscreen should help quite a bit. Wheels/tires will help a LOT. Bin the rear exit exhaust and get a Ti silencer from Ammo at http://raceco.com/.

                      Other suggestions: Carbon fiber bits (seats, fenders)...you could even go whole hog and re-panel using RIF carbon panels! Lightweight brake calipers? Ditch the heater (if fitted), ignition switch, wiper motor. Fit ali light blocks (replacing those heavy rubber bits), ti stone guards (or just do without), and remove the headlights when racing.

                      BTW, the duratec 2.3L is able to be re-sleeved to 2.5/2.6L...good for over 300hp. :shock:
                      Tom "ELV15" Jones
                      http://PIErats.com

                      Comment


                      • #12
                        I think that you can save 10-15 kg with an elite sequential trans. The guy is here in SD and we should visit him soon.

                        How about an CF bellhousing and propshaft?

                        Kumho tires are very heavy compared to slicks or ACB 10s. About 7-9 pounds per tire, I think.

                        The heater weighs 12 pounds, almost 1% of my car weight!

                        See ya @ the Streets!!

                        Comment


                        • #13
                          Yeah! Get all of that stuff!

                          Just think how much lighter your wallet's going to be too! Your wife is going to rip me a new one, claiming your new poverty is all my fault. But that's ok - I can take the heat. It's all for the right cause.

                          P.S.: I was right at 90 kilos this morning (P-D).
                          Chris
                          ------------
                          A day you don't go a hundred is a day wasted

                          Comment


                          • #14
                            Thanks for the tip.

                            My official explanation will be: "Chris taunetd me into it!"

                            On the other hand, Miwako just got a new Nissan 350Z to play with, so her economic sense is a bit new-car numbed right now. A fact that I intend to exploit shamelessly.

                            /Magnus F. (93 kilos.)

                            Comment


                            • #15
                              Magnus, Stan, I sent you the spreadsheet with the cornerweight results.
                              Chris, I don't have your e-mail but since you had the lightest car anyway here the result (sorry, the Excel formatting got lost and it becomes almost un-readable...). Please note the corner weight balance is right on the money!

                              Measured weights (leverage factor=2.0) Total % F/R
                              LF 175 156 RF 331 44.8%

                              LR 217 191 RR 408 55.2%

                              Total 392 347 739

                              % L/R 53.0% 47.0%

                              Ideal weights
                              LF 176 155 RF Total car weight
                              Pounds Kilogram
                              LR 216 192 RR 1478 669.534

                              ^^^ Chris' car - with driver - unknown fuel ^^^

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