Suspension setup using FCM Spreadsheet?

Wheels, Suspension, Brakes & Tyres questions and answers

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manga_blue
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Location: Moruya, NSW

Re: Suspension setup using FCM Spreadsheet?

Postby manga_blue » Fri Feb 14, 2014 9:27 pm

The sensitivity is really pretty subjective too. The +2/-1 that I mentioned is how much I like it to vary to suit my driving style and my enjoyment of the car at the limits. In reality other factors can alter the balance to the point of absolutely swamping the setup values, in which case you just accept it and adjust to drive accordingly on the day. Driving style can trump everything.

At November's interstate challenge meet I was having major front tyre problems, basically bugger all front grip. This got to the point in the last session where a couple of my Vic mates following me said I was going through turn 2 at almost full positive lock (full understeer :D). It was definitely not the way I wanted the car to feel but it was still running mid 13s with a flat motor and gear selection problems (again :twisted: )
’95 NA8

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Tony
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Location: Bathurst, NSW

Re: Suspension setup using FCM Spreadsheet?

Postby Tony » Fri Feb 14, 2014 10:15 pm

Once I got my old NB8A setup properly it felt very planted; lots of grip, very neutral and forgiving. I then swapped the suspension across to the SE (same sway bar settings), got it corner balanced and aligned. Obviously I expected the same response.

However, on the fast sweeping corners at Eastern Creek the car felt unsettled and skittish mid-corner; unlike my old car which felt great. I played with the bars which improved the feel dramatically; some tweeking of the wheel alignment finished the job. Without thinking about it too much I put the variation down to the stiffer NB8B chassis and perhaps a tad more weight.

Notwithstanding any improvement due to the amended wheel alignment, the variation in FRC according to the spreadsheet went from 57.4% initially to 58.5% after the adjustments. That's only a 1.1% variation between "not so good" and "fairly good".
'09 NC2


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