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5) I have my tires and wheels, but do not know how to calculate the effective spring rate of that combination or how to apply it in conjunction with the calculated wheel rate for any particular spring.
The data is not publicly available, so for an apples-apples comparison to what data is publicly available, you pretty much have to leave it out anyways. It's not as accurate, but it's more precise.
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i) The spring rate should not be less that 1/2 the estimated weight at each wheel.
Remember, we're talking wheel rate, not spring rate. I'd also argue more like 1/2 +/- 20%, with a bit more rear than front. Adding some sway bars would more easily let you stay on the less than 1/2 side while still maintaining good roll control.
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ii) The upper bound would be 1.0 times the estimated weight, which is what a race car might have.
That would be a 3.13Hz frequency, with a natural droop of just 1 inch. That's not just racecar territory, that's high-downforce racecar territory.
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iii) The GAZ Excel spreadsheet is a good tool and will give me a figure for suspension frequency, which in my case might be best in the 1.5-1.7 range. I'll be using some model of GAZ coilovers anyway.
Make sure that their equation either includes the spring angle angle in the motion ratio when it's squared, or that it gets squared if treated as a stand-alone term in the equation. Many, if not most, online resources seem to get this wrong.
https://grassrootsmotorsports.com/forum/grm/wheel-rate-calculation-discussion/241074/page1/Quote:
My first question is, "What additional information do I need to calculate the spring rates at front and rear and get the coilovers ordered?"
Next up would be looking at Lateral Load Transfer Distribution or Front Roll Couple (aka LLTD or FRC). See the 'chassis calcs public' attachment.
https://www.locostusa.com/forums/viewtopic.php?f=5&t=19253&view=nextEdit: Looks like I also need to go back and find those motion plots to repost on the previous page.