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Software, Calculators

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10 files

  1. S30 RC Calculator

    Simple roll center calculator for the Z car based on measuring the angle of the control arm. I tried to list all the definitions and assumptions. Please drop me a comment if you see any errors or improvements. I checked it against my professional software and got the same values when using the same inputs so I think the math is correct.



  2. Turbo Engine Flow Map Calculator

    Input the yellow fields. Take the results to a Turbo Flow Map and see where you stand. This will help you design an engine and turbo that work well together.




    I hate reading nomograms! So I took the one on the second page of this Holley document on carb selection (for sizing mechanical secondary Holleys):
    http://holley.com/da... nical/Selec...
    ...and fit a second order polynomial to the inputs (minimum WOT rpm and displacement in cubic inches):
    cfm = 0.000886*WOTrpm*disp + 0.000159*disp^2 + 0.0000066*WOTrpm^2 - 0.345*disp - 0.0554*WOTrpm + 439
    Checking it against that nomogram, it seems to reproduce the results of drawing a line across from WOTrpm through disp to find the cfm needed, within +/- 6 cfm, when I checked it against the 10 data pairs I used to read off the graph and then check it. It all really hinges on how closely you read that graph to come up with the input data, and how accurate the data they used to make the graph with actually was. I used a graph that I tweaked to exactly match each of the 3 axes of the original graph, zoomed in to very precisely read the data off of lines I drew from several WOTrpm/displacemt pairs over to the cfm axes, as well as one graph for each axes to find the non-linear formula for each of those. Like I said, I geeked out.
    Here's a spreadsheet I made up to do the calcuations:
    (same file as the download, the link is provided above too)
    All of my work is shown on the calcs sheet, if you want to check my math
    Just put the WOTrpm (minimum rpm for WOT use) and displacement (in cubic inches) in the yellow boxes and the answer appears in the magenta cell to the right of those.
    Watch out, we have no idea how accurate the data in that original graph is! Also, they make no mention of whether the type of boosters are, the throttle plate size, or the venturi size. I believe all of these play in the selection.
    Also, note that Holley and BG may have a name for a carb based on a cfm number but the total cfm they flow can largely differ. BG's 650 DP Mighty Demon flows 830 according to them, so if you pull 830 off of that graph, you'd want a 650 Mighty Demon!
    By Pete Paraska



  4. CFM Calculator for Carbs

    CFM Calculator for Carbs using this common forumla "(CID * RPM /3456) VE = CFM" One can enter the CID RPM and VE to get CFM, or do it backwards to get the maximum RPM from CFM, CID and VE.



  5. Conversion Assistant

    Conversion Assistant
    For converting any unit into any other unit.



  6. HP under Curve Calculator

    Hp under curve Excel Spreadsheet.
    To Use:
    1) Remove my Dyno sheet and replace it with your own.
    2) Incert your Hp numbers into the Hp column.
    3) For increaced accuracy lower the N-Size.
    Contributed by: 240jz



  7. Quarter Mile Calculator

    This is a quarter mile calculator that uses visual basic for applications within excel to calculate position, velocity, and acceleration based on vehicle parameters.
    The input accepts the following parameters:
    drag Coefficient
    rolling resistance
    traction coefficient
    shift points
    transmission gear ratios
    differential gear ratio
    Tire Diameter
    Engine Torque Curve
    The engine torque curve assumes rear wheel torque and accepts 7 datapoint pairs. The program interpolates between the given data points using cubic spline interpolation (gives a smooth twice differentiable curve).
    The output to the dialog is all of the drag strip parameters (60' time and speed, 330' time and speed, 660' time and speed, 1000' time and speed, and quarter mile time and speed). Further, all of the data for a 50 second run is output to a spreadsheet (100 samples per second).
    The program predicts the times for my car to within 0.1 second and within .5 mph.
    Currently, the program is specific to a manual transmission powered car. I would like to expand it to include automatic transmission equipped cars. The source code is open and I invite criticism as long as it comes with suggestions for improvement.
    IMPORTANT: In order for this program to run properly, you must set your excel security level to medium. And then when you are prompted to run macros say yes.
    Contributed by: 74_5.0L_Z



  8. Toe-in converter

    Most of us think of toe-in as measured in inches, but my local alignment shop's machine only measures in degrees. So I built this spreadsheet to convert from one to the other.
    Contributed by:Zmanco



  9. Datalogging software & source, Mac compiled & PC

    These are a couple of pieces of software I've developed for tuning ECM's. I've included both OS X executable as well as the code itself. They're written in RealBasic, a cross-platform, object-oriented, compiled version of the old stand-by language Basic. I'm hoping that someone who knows what they're doing can take a look at these programs and whip them into shape, or at least give me some good suggestions, hints, ideas - I'm not a programmer (as will be obvious once you look at the code).
    The first one is called "ALDLx". It's a data logger for the '7730-and-family ECMs. It has been patterned after a couple of older pieces of software (ALDLMON and WinALDL). It was designed from scratch to work via a USB/Serial adapter. As it stands it works pretty well (for me!), but it's spaghetti code at best (in spite of being Object Oriented). It compiles under 10.3 and 10.4, hasn't been tried under 10.5. It also compiled it on the Windows 98 version of RealBasic, as an experiment, but didn't have a chance to try it.
    The second one is "PKTx", is a little utility that does only one thing: sends a .bin file from the Mac via USB/serial adapter to a Romulator. That's it. However, the killer app is that you can run a program like TunerPro or TunerCat under Virtual PC, modify it in a "shared" folder, and send it up to the Romulator on the fly every time you save it. So you can datalog with ALDLx, modify the .bin with TunerCat/TunerPro, and send it to the Romulator all in one smooth action.
    Anyway, if there are any brave programmer/gearhead types out there, I hope you take a look at these things and can maybe do something with them.
    Tuning Distro.zip is approximately 7.6 mb in size.
    Contributed by: strotter



  10. The L-Engine Calculator

    Here's the calc for Z internals and CR's and stuff.



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