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  • #91
    Originally posted by pbf777 View Post
    ...

    Your concern for reasonable transition from the throttle body to the intake is valid, but a "torturous" path should not create the difficulties as you describe at low speed and idle; but could create horrendous air and fuel distribution at higher velocities. ...

    Miscellaneous ramblings that may or may not be useful. Scott.
    Scott, this is a TBird site, not Ramblers.

    Not a lot of difficulties with idle, just cruise. At 70mph the engine is churning over at about 2600RPM, so that's a lot of air going through that passage.

    The new Victor intake is scheduled to arrive late next week. There seems to be a basic consensus among those I've talked to that this should solve the issue.

    Now I have the other issues that go along with this to contend with- crankcase gas recirculation, fit of my original air cleaner...

    Comment


    • #92
      There are several threads on the FAST forum about single plane intakes and the FAST EFI throttle body sytems. Reading through them, the issues are similar if not identical. I'm feeling better and better about this swap.

      Comment


      • #93
        Not at odds with your decision of the Victor intake, and I am very interested in the results (maybe I'll learn something on your dime!).

        Beyond solving the transition concerns between throttle body & intake (definitely a plus, and it looks cool to!) what other effects may one actually encounter?

        As compared to the existing unit, it presents a 360 "open" plenum and more direct ports shapes (less bends & kinks) all of much greater cross-sectional area & volume. Effect? Typically, the intent would be to increase upper R.P.M. power (well beyond 2600 R.P.M.s & part throttle values), at the expense of the lower R.P.M. values (this is, kind of a racy intake manifold). Well, keep in mind, you are attempting to use E.F.I. vs. a carburetor, and therefore one feels some redemption/salvation at hand, and such is probably true. And this increased area & design will dampen reversion effects somewhat if that were an issue.

        The E.F.I. throttle body solves the difficulties of the carburetor, in that one must create reasonable "signal" to the atmosphere below and thru the carb. to draft/siphon fuel into the air stream. But, because it is a T.B.I. system (vs. individual port injection), the manifolds' inlet port values must still contend with the responsibility of maintaining fuel in suspension to the cylinder. Obviously, as the sectional area of the port passages increases, along with the plenum volume where initial mixing (air & fuel) takes place, with a constant in requirement/consumption, a loss in velocity and turbulence is expected. Hence, one may expect an increase in fuel droplet dimension both at initial vaporization intent within the plenum area, and failure to exhibit superior further vaporization and mixing as the air/fuel columns proceed thru the ports en route to the individual cylinders, even perhaps to the point of condensing or "wetting-out" upon the port walls (at lower R.P.M.s), at best only leading to inefficiency. .

        Am I implying impending doom, no, and I think you already understand most, if not more, but still, it will be interesting. Scott.

        Comment


        • #94
          Here's the link to the FAST forum showing current threads.

          http://www.cpgnation.com/forum/forum...ort-forum.235/

          Several threads on throttle body intakes and dual vs single plane intakes. The old rule of dual plane for street, single plane for race, doesn't apply for this situation at all. Guys are seeing more low end torque with the single plane and much better driveability. One noted that his black soot problem (out the tailpipes) was history. That alone is a tell-all of what is occurring with the dual plane. Some cylinders are rich; the single O2 feedback loop is attempting to hit the target, causing other cylinders to be lean. The rich ones are draining the gas tank and dumping unburned fuel out the pipes.

          Also, I'm not the only one there complaining about FAST's advertising: "NO intake manifold change".

          I also note that the Victor for the FE engine comes in three flavors.
          • 2936 for 4150 style carbs. Or in my case, the FAST EZ EFI 1.0.
          • 2937 for 4500 style carbs.
          • 29365 for throttle bodies. This is the same casting as the 2936, but has 8 injector ports drilled and tapped for a more advanced multi-point or sequential injection system. Obviously, Edelbrock has tested this casting for FI.

          Comment


          • #95
            The bulk of the engineering endeavor encompassing the 180 dual plane intake (as relevant in this discussion) was in order centrally locate (within the the "V") and add in the function of the carburetor.

            As I eluded to previously, the "180" design provided "balanced" access by the engines' pumping cycles of the eight cylinders to the carburetor, by isolating bores/venturis to intermittent cylinders in the firing order, this attempting to provide a more rhythmic and balanced draw on the carburetors' fuel metering system, thereby providing better function/control of the mixture values by the carburetor. Note that this is not always ideally achieved, but this was the idea anyway.

            But, with E.F.I. you are correct,........ who cares! We don't have any concerns or need of this engineering, as we are mechanically forcing fuel into the air stream at will (as programed).

            The "dual-plane" effect is only the mechanical engineering (ducting if you will) required for the 180 access of the eight cylinders, in two separate banks (American V8, left & right), further, dividing two cylinders from each of these two banks, bringing each pair from each bank, pairing with apposing bank cylinders to create four each, and routing to the centrally located carburetor (providing as close to equal distance runners as possible & for compact packaging). Talk about a torturous path! And as stated previously, at times the runners will be of different lengths and sectional area, sometimes not by choice, but other instances intentional by design, for a different effect of creating cylinders which reach peak torque & horsepower values at different R.P.Ms.

            Again,...... with E.F.I. you don't need it! Not for the 180 requirement anyway, but you would lose the other function.

            Manifold engineering concerns for providing "signal" for reasonable function of the carburetor are nonexistent with E.F.I. yes. But, with the T.B.I. system, this is not what is sometimes referred to as a "dry manifold" system, fuel is still present within the intake runner, and needs "tending to" for best operation. Scott.

            Comment


            • #96
              The instructions that I read prior to purchase said specifically that this manifold would not fit a TBird. I accepted the challenge.The intake arrived last week and after dry fitting and some careful measuring I had a machinists make some modifications.

              1. The oil fill boss was milled to accept my original fill/ vent tube.
              2. The throttle linkage flange was lowered and leveled.
              3. I used a short piece of 3/8" pipe for the heater hose bypass. I had him turn the exposed portion for better sealing on the short bypass hose.
              4. Here's the key here: I had him cut 1/4" off the front of the carburetor flange, bevelling down to 0" at the rear edge.

              This last modification leveled the original air filter and gives me 1/2" clearance to the hood.

              Here's what it looks like after the modifications and two coats of Ford Engine Black.
              Attached Files

              Comment


              • #97
                Mike block sanded the lettering to make it stand out against the black. I think it looks pretty sharp. Idle quality is better. We finished the job at 5pm, not exactly the best time to take a test drive. Tomorrow we'll see if I have an improvement.
                Attached Files

                Comment


                • #98
                  I don't have a good shot of the rear, but I am using the two 3/8" barb fittings on the rear of the throttle body (below the throttle plates) for my vacuum source:

                  One does my PCV, brake booster and transmission modulator.

                  The second does my cabin accessories and modulates the fuel pressure regulator.

                  Comment


                  • #99
                    Results of the test drive went good. Smoother than before- not perfect- but a definite improvement. I was able to increase my AF rations on all three settings. I'm now running 14 at idle, 14.5 at WOT, and 14.7 at cruise.

                    Here's what it looks like with the air cleaner installed. To the untrained eye, it's fresh from the factory.
                    Attached Files

                    Comment


                    • Steve very nicely done...
                      Dano Calgary,Alberta Canada
                      Thunderbird Registry
                      58HT #33317
                      60 HT (Sold )

                      Comment


                      • Originally posted by Yadkin View Post
                        I was able to increase my AF rations on all three settings. I'm now running 14 at idle, 14.5 at WOT, and 14.7 at cruise.
                        Just some input from the peanut gallery: as you proceed in your tuning endeavor, always address your starting point with known rich fuel mixtures and known conservative timing values (reasonable of course). Then remove fuel sums progressively for best effect, acquiring what is often termed "Lean-Best-Torque", and add timing in the same fashion. One must be attentive with the process to acquire conclusions as one proceeds, so as to respond (tune) appropriately. Do not get to "hung-up" on the numbers as stated, as they are solely relative to your experience, but can provide a guide (perhaps a wake-up call!).

                        Keeping my last statement in mind, one is generally of the thought that 14.5 @ W.O.T. would be less than ideal (typically maybe 12.5 range?); and if accurate (and that's the catch!), perhaps even somewhat hazardous to survival of your engine. Remember, draw your own conclusions (perhaps with some guidance, as we all need some), and follow your own intuitions for best results.

                        Very nice & professional appearance. Scott.

                        Comment


                        • Still tweaking on this car, found a little issue with the fuel pressure regulator and got it mostly fixed.

                          I got onto I40 the other day on a two-lane ramp and a guy in a Kia "gerbil car" was neck-and-neck with me, so naturally I put my foot to the floor. The transmission never downshifted and I pulled away from him, but without the authority that I expect.

                          That night I started looking at the throttle linkage and found out that along with my kickdown off, the throttle plates weren't opening up fully. The linkage placement is slightly different with this new intake, and I never made the necessary adjustments. So I readjusted everything, reset a new base tune on the EFI then took it for a test ride.

                          After warming up I stopped for gas, stepped on it a little bit on my exit and unexpectedly spun the tires. Looks like I may be getting the tune right. When I got to the highway on ramp I put my foot to the floor and got up to 70 in the blink of an eye. Upshifting into third resulted in both back tires chirping.

                          I've driven V8s my whole life but this is my first performance big block. I'm not happy with the gas mileage but dang it's fun.

                          Comment


                          • I'm not happy with the gas mileage but dang it's fun.
                            Gotta pay to play!

                            Comment


                            • Joe isn't that the truth
                              Dano Calgary,Alberta Canada
                              Thunderbird Registry
                              58HT #33317
                              60 HT (Sold )

                              Comment


                              • Originally posted by Joe Johnston View Post
                                Gotta pay to play!
                                At least I know it's all getting burned, along with tire tread.

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