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PostPosted: December 17, 2013, 2:16 pm 
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MV8, I'm slow getting around to it, but I'm looking thru all your posts above and am left wondering about some things. I'm not sure the math is completely right in Vsusp. It would seem to me that changing the KPI on the spindle and adjusting arms to suite ( basically shortening the upper arm? ) should not produce a milder camber correction curve, it should accentuate it. I can run the actual models on my browser here at work so I will try it tonight.

I also don't remember if I mentioned before that the Mustang II/Pinto spindle is available in two KPI values. There is a 7 KPI angle available and used by the dirt track oval racers. They obviously spend a lot of time turning left while steering right. In that condition lower KPI spindles work better and in fact may work better for us too. These have a stock height spindle pin.

I used the drawings fromt he Wilwood MII/Pinto spindle to make my drawings and they are also what SeattleTom is using in his model, if you would like to compare.

SeattleTom, I was going to write a note to you too, but lunchtime is over...

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PostPosted: December 17, 2013, 3:00 pm 
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I was thinking the same thing initially, but as camber gain per degree increases, the chart flattens out since it is the change in camber per degree of roll, not the actual gain on the chart. If we roll the chassis 5 degree and the chart shows 2.5 degree camber with zero camber at zero roll, then we have half a degree camber gain per degree roll.

What are the vsusp dims for the spindles in the two kpi configs?


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PostPosted: December 17, 2013, 7:40 pm 
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Miatav8,MstrASE,A&P,F wrote:
Not sure what you mean by input generator. It appears to be a list of specs that have to be entered one at a time into vsusp.
MV8, you are right, for the T-Bird version what is “generated” is a list that needs to be keyed into Vsusp where the data gets recorded again. And on the spreadsheet, some of the data on page 1 is just copied to the list on page 2. Where this spreadsheet is useful to me is doing some of the math and helping keep track of other chassis parameters. I prefer to work in things like the drop in heights between the inner and outer pivots, etc. and then let the spreadsheet calculate the Y dimensions and the control arm lengths that Vsusp requires.

The Wilwood Mustang II version is a little different. It started life creating the 3D data points that need to be keyed into Wishbone. It does a whole lot of trigonometry calculations based on spindle geometry, caster, camber and a number of other Car9 chassis setup options. In the current version, the Vsusp list at the end is just a remapping of that 3D data, being mindful that Wishbone’s Z’s are Vsusp’s X’s, etc. And yup, it still needs to be keyed in.

So these two spreadsheets are definitely not rocket science, but they do help simplify, organize, pre-calculate and document things a bit, at least for me. And as the bard says, “Math Sucks.” :)

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I showed my specs photos by selecting the spindles tab then moving the cursor to where the dims of the arms were overlayed, selected "PrtScn" on the keyboard, then pasted that into paint and cropped.
Good tip, thanks. PrtScn and Paint are kind of low profile and easy to miss. :oops:

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PostPosted: December 24, 2013, 3:19 pm 
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Location: Arizona
Vsusp update
    - Fixed IE drag 'lock-up' bug: (thanks Seattletom for reporting it)

Also, I highly recommend using another browser besides Internet Explorer when using VSusp. IE has a maximum URL length of 2083, and this can some of the project link to be truncated :BH: Chart settings will be affected first. Other browser seem to work fine. Chrome run VSusp the best.

More details about the update

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PostPosted: February 13, 2014, 4:17 am 
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Ahhh, had 95% failure rate opening Vsusp lately, message is "Javascript disabled or scripts not loading" but of course my Java is fine as is the version, have deleted and updated it, have run all the tests and sought info from the net including Java and Chrome etc etc ...

It's the only Java site that I'm having issue with, in fact have had never even seen the message before it started at Vsusp and as I mentioned it's 95% of the time, actually loads on occasion and runs faultlessly.

Oh and that's from home and work so different computers, different IPS, etc.


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PostPosted: February 13, 2014, 3:35 pm 
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Cheapracer,

I didn't participate when this topic started because I was using internet explorer. I eventually installed Google Chrome (which is free) just for vsusp. Install and use have been great for someone who hasn't even started using a "smart" phone yet. I'm still sporting a ancient 2g phone.

What browser are you are using?

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PostPosted: February 13, 2014, 10:22 pm 
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I was one of the original public beta testers for Chrome and have never looked back ...

I was unique, along with the other couple of million beta testers :mrgreen:


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PostPosted: February 18, 2014, 12:57 pm 
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cheapracer wrote:
Ahhh, had 95% failure rate opening Vsusp lately, message is "Javascript disabled or scripts not loading" but of course my Java is fine as is the version, have deleted and updated it, have run all the tests and sought info from the net including Java and Chrome etc etc ...

It's the only Java site that I'm having issue with, in fact have had never even seen the message before it started at Vsusp and as I mentioned it's 95% of the time, actually loads on occasion and runs faultlessly.

Oh and that's from home and work so different computers, different IPS, etc.

Just saw this message -- Cheapracer: which browser(s) are you using? Also could you check for any javascript errors in the console (shortcut: "ctrl+shift+j" in FF or Chrome)? If any, could you please paste them in?
Thanks -
Rob

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PostPosted: May 31, 2014, 11:46 pm 
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Sad to say it's just getting too much, works perfectly one day then the next it just "Javascript disabled or scripts not loading" and this is for 3 different computers in 3 different locations.


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PostPosted: June 1, 2014, 8:33 pm 
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cheapracer wrote:
Sad to say it's just getting too much, works perfectly one day then the next it just "Javascript disabled or scripts not loading" and this is for 3 different computers in 3 different locations.


I've used vsusp for 4 months or so on 2 computers in 2 locations on chrome and have never had a single problem with it loading, often loading it multiple times daily in both locations. Just my experience

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PostPosted: June 2, 2014, 12:57 pm 
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FWIW it's the same on Firefox and Explorer and yes I have deleted and reloaded Java etc etc ...


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PostPosted: June 2, 2014, 8:00 pm 
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Cheapracer,
What version of java are you using? If it is 7-55 you may need to go to the security tab for Java, in the control Panel and permit locostusa.com . Something new in java.
Walt


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PostPosted: June 15, 2014, 11:15 am 
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Hey Cheapracer: sorry to hear about the VSusp trouble. Thanks for posting the error message.

It sounds like one of the scripts is occasionally inaccessable via your internet connection. Could you try opening this link? https://ajax.googleapis.com/ajax/libs/d ... jo/dojo.js This script is hosted on a different server than vsusp, and if it's only loading sporadically, this would cause the kind of problems you're seeing.

Thanks,
Rob

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PostPosted: July 29, 2014, 5:33 pm 
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Like many here, I’ve been spending hours in front of the VSusp program. My highest complements to the author.

Now I need to get out in the shop and make something. How about a real life VSusp model? 2d for now. I recommend the model be a half or quarter scale so a 60 inch tread will measure 30 or 15 inches respectively on the model.

Imagine the VSusp image with your suspension geometry entered. To scale, cut out a ¼ inch plywood profile to match your chassis and drill ¼” holes in this plywood “chassis” where your inner control arm pivot points are. Leave lots of room in this area for future holes to explore different suspension settings.

Cut out a similar scaled plywood profile of your tire/upright assembly and drill holes in these where your outer pivots go.

Make your upper and lower control arms from ¼” all-thread rod.
The pivot points are eye bolts (1/4” diameter eye, ¼” – 20 threaded shank). Slip these over the all-thread to their scaled position and secure with nuts and washers on both sides of the eye.

Put the shank of the eye bolts in their appropriate holes on your chassis and tire/upright assembly profiles. Secure with a washer and self-locking nut on both sides of the plywood just tight enough to permit eye bolt to rotate. These are your poor man’s Heims.

I like to rest the whole shebang on a piece of 2’ x 4’ smooth-faced plywood set up at a 60 degree angle. Put a cleat at the bottom to represent the road surface and keep everything off the floor. Put some pads behind your plywood model so it slides over the plywood and have at it.

To get realistic, add some suspension springs. Make the all-thread lower control arms to extend past their inner pivots toward the center of the car. Attach one end of a screen door tension spring to this extension and the other end to a convenient point above on your plywood chassis. The springs will be in tension but that doesn’t matter, we’re after the spring rate at the wheel regardless of the spring type. We’ll adjust the springs in a minute.

Now, put a peg or something in your plywood chassis where you think the center of gravity will be. Tie a string or wire to this peg and hang a weight from this string so it pulls down on your chassis while the chassis/suspension assembly rests on the backing board against the cleat on the bottom of this board. Adjust the spring tension and the weight until you get a reasonable workable value for each. With the springs and weight adjusted to get your chassis at ride height, your car is at one g. Tie another string to your weight and pull it laterally to simulate lateral loading combined with your vertical loading. You will have to put a pin or something at the bottom of one of the plywood “tires” so your car doesn’t slide off your board and into the ditch. If you pull laterally on the weight instead of the C.G. pin, your angle of the string at the pin gives the combined vertical and lateral force components. If you can pull your weight over to where the string from the peg is at a 45 degree angle, you are pulling one g lateral, along with your vertical load.

When my wife catches me experimenting with this she always says coldly, “I see you’re dancing with ‘that thing’ again”. Someday I’m going to mount a couple of Cadillac Dagmars on it and show her some real dirty dancing.

Bob


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PostPosted: August 9, 2014, 12:17 pm 
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How does everyone allow for static tire deflection in Vsusp? Do you reduce the "effective" tire diameter? Raise the ground level during analysis?

Thanks all.

Bob


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