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this one is i have taken from sydneykid in the coilovers thread. we got to talking swaybars.

Thanks for the advice Gary. Atm im on a full whiteline stabiliser bar kit with urethane bush set, camber front and rear and pineapples set to standard.

the front adj blades on the swaybar im pretty sure though i could only get set up at 2nd and 3rd hole. can the front swaybars be adjusted any further? how can i do it? the rear is at full hard.

What size bars are you using? My guess is the off the shelf 24 mm front and 22 mm rear, which is too narrow an adjusment range for the track work you are doing, grip or drift. You should really be looking at 26 or 27 mm front and 24 or 26 mm rear. I don't recall what model it is, if it's an R32 then you need 4 adjustment settings on the front and 3 on the rear, standard (off the shelf) is 3 front and 2 rear. If it's an R33/34 then you need 6 adjustment settings on the front and 3 on the rear, standard (off the shelf) is 5 front and 2 rear.

You should also be using spherical bearing links on the bars to give you the instantaneous effect, plus increase the feel as you need as little dampening of the response for track work. They will need regular replacement, even the Whiteline greasable and dust covered ones. Just like brake pads they will wear out, they are a consumable after all.

To give some adjustment for the usage patterns that you have, you can't run spring rates that high, anything much over 5 kg/mm front and 4 kg/mm rear will negate the effect of any adjustment (bars, shocks or geometry) that you do. Use the bars to control the roll, that's their job after all and then adjust the rear subframe geometry to suite the traction requirements. At the moment you have nothing to adjust that will help with your problems.

Cheers

Gary

Somethings to think about;

You would need to use twice the spring rate to achieve the same anti roll as a stabiliser bar. Why? Because the inside wheel goes down the same amount that the outside wheel goes up. So a stabiliser bar has twice the movement for the same amount of roll as a spring, hence twice the amount of resistence to roll. Only the outside spring resists the roll, the inside spring does nothing.

When you are not going around a corner, the stabiliser bar does nothing, so you get more traction from the softer spring rate.

Stabiliser bars are easily adjustable, spring rates are not. If, on any given day, you need more or less front or rear anti roll you can't easily, quickly or cheaply adjust it with springs. That's why (when the regs allow) race cars have driver adjustable stabiliser bars.

Diagonal weight transfer is best resisted with anti roll, not spring rate. Under corner exit acceleration the outside rear tyres take a large amount of weight transfer, this manifests itself as lift to the inside front tyre. Reducing inside front tyre grip means that the outsdie front tyre is carrying more of the cornering load than would eb the case if the diagonal weight transfer was a resisted by a stabiliser bar. Excessive outside tyre wear and inability to maintain consistent lap speed due to overheating are all systems.

Too little anti roll has side effects. One of which is the need to run excessive amounts of camber, front and/or rear. This reduces the contact patch of the tyre for straight line acceleration and braking.

Running an excessively high spring rate becuase of a lack of antir roll has a few more side effects. One of which is the need to run excessively high rebound damping in the shock absorber to control that higher spring rate. This means the shocks resists (slows down) the downwards movement of the suspension and makes it more difficult to keep the tyre in contact with the road surface. Skipping from small bump to small bump is not good for traction.

I have several more pages in me if necessary, if anyone remains unconvinced.

Cheers

Gary

Selby's swaybars (not sure if they make swaybars for Skylines) -

http://www.hotfrog.com.au/Companies/Selbys-Swaybars

K-MAC swaybars (As far as I know the prices on the website are in US dollars

and they make swaybars for R32, R33, R34 in non adjustable and adjustable).

K-MAC website -

http://www.k-mac.com.au/

Swaybar prices -

http://www.k-mac.com.au/pages/tuning/listofkits.htm

Also I noticed they can custom make springs.

Edited by SKYPER
Selby's swaybars (not sure if they make swaybars for Skylines) -

http://www.hotfrog.com.au/Companies/Selbys-Swaybars

K-MAC swaybars (As far as I know the prices on the website are in US dollars

and they make swaybars for R32, R33, R34 in non adjustable and adjustable).

K-MAC website -

http://www.k-mac.com.au/

Swaybar prices -

http://www.k-mac.com.au/pages/tuning/listofkits.htm

Also I noticed they can custom make springs.

I thought Selbys was Whiteline?

Anyway thanks for the info and links .

they are hollow bars.

size f: 24.2mm

size r: 27.3mm

i use the gtr spec ones but they bolt onto my gts fine

gts spec ones are

f: 27.2mm

r: 23.0mm

Where did you snap these up from and how much did they set you back???

they are hollow bars.

size f: 24.2mm

size r: 27.3mm

i use the gtr spec ones but they bolt onto my gts fine

gts spec ones are

f: 27.2mm

r: 23.0mm

Front GTR (4wd) bar won't fit a GTST (2wd), plus it is too soft a rate.

Cheers

Gary

Gary,

I have forgotten....what are the size of the sway bars in the GB that I have? :P

From memory, 24 mm solid front adjustable and 22 mm solid rear adjustable.

Minimum adjustment is equivalent to a 27 mm hollow bar, with 6 steps of around 8% increase each on the front.

The rear is equivalent to a 24 mm hollow bar, with 3 steps of around 12% increase each on the front.

All the Jap hollow bars I have tried are grossly underdone. As an example, we swapped John's 300ZX hollow bars for some solid bars, backed off the spring rates a bit and it was 1.5 seconds a lap faster at Philip Island.

Cheers

Gary

  • 2 months later...

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