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Base Suspension Set-up
Nosey - 17/5/09 at 09:15 AM

Hi All,

Getting ready for my first hillclimb the 31st and wondering if anyone had advice on a base suspension set-up? It's a 2ltr 16v, 6x13 fronts and 7x13 rears, still have to sort tyres but probably Avon slicks. Without having driven it yet, I have 0.5 degrees toed in, 1.5 degrees camber and approx 4 degrees castor?


mark chandler - 17/5/09 at 10:10 AM

Ride height made most difference to me, make it as low as possible.


Nosey - 17/5/09 at 10:50 AM

It's 4.25 inches to the bottom of the chassis at the front, 4.75 inches at the rear, with the sump an inch lower than the chassis. I suppose it's a drive it and see job.


oldtimer - 17/5/09 at 12:14 PM

Is there a 'best' castor angle?


procomp - 18/5/09 at 07:17 PM

Hi

Assuming it's the car in your archive. Then set the front ride height so the front wishbones are level ( well the inner pivot bolt and the outer ball joint center) Rear ride height level to 15 mm higher than front. Tracking is debatable but try 1 mm toe in or if suffering lack of initial turn in on the corners try 1-2mm toe out to gain better turn in but that's all debatable depending on driving style etc camber as you have. 4 deg castor is not too bad but ideally could do with a min off 5 deg but don't worry for starting out with sort later when more experience with the car.

Being live axle if it's over steering badly then drop the rear ride height. If it's under steering try raising the ride height another 5mm But no more than 20mm higher than the front ride height in total. And check that the rear dampers are not running out off travel in both bump and droop. That will get you started and you can experiment from there with more running of the car. Espesialy with diferent spring poundages ect.

Cheers Matt

Ps what spring poundages do you currently have ?.



[Edited on 18/5/09 by procomp]


sevaun - 26/6/09 at 12:26 PM

Hi the info above should get you there or there abouts. I've run my car in hillclimbs for last 4 seasons and found the greatest effect on handling is to fit front and rear roll bars. At first I ran only a front bar but found that to get enough roll stiffness I ended up creating to much understeer. Adding a rear bar means I can now increase roll stiffness without increasing spring rates and balance out the understeer by stiffening the rear bar.
I found 2 seconds immediately at Harewood with the rear bar fitted.
On the subject of castor. We all know the problem with the book chassis castor set-up(or lack of it). I set mine at 5 degrees and find this is about spot on for feel and turn in. When I went for SVA the tester at SVA centre commented that my car had the best self centering and feel of most Locosts/ Westfields he'd tested


Hope this helps

Richard



[Edited on 26/6/09 by sevaun]