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A Little Understeer?

nuffsaid
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nuffsaid Veteran

nuffsaid

Posted
Posted

Hi all

I have Tein Super Streets installed, riding at 345mm all around, with the damper settings set to the 4 softest setting (of 16 settings) as recommended by Tein. Spring rates are 5k front and 4k rear.

I also have front camber at -1 and rear camber at -0.5 and about 7 degrees of castor at the front.

Tyres are 235/40/18 Falken FK451s.

I have also fitted a 24mm front sway bar on full soft, and a 20mm (to match higher rear spring rate) rear bar on the softest setting.

The problem is I am experiencing some understeer, and not much over, especially on wet streets. What settings can I change to reduce the understeer? Do I increase the rear bar setting to medium?

Note: I dont want to make the rear overly stiff as that will ruin the ride, I hear changing sway bar settings might do this, but perhaps not so much that its noticeable.

Thanks!

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BHDave Grand Master

BHDave

Posted
Posted

Stiffen the rear bar up a touch. I noticed very little difference in ride quality when mucking around with bar settings though to be honest i was more interested in how the car went through corners than any increased harshness in ride.

Al Grand Master

Al

Posted
Posted

If the rear is handling fine why mess with it? Maybe he does not want to unsettle the ass-end to make the front turn in.

Have you tried to loosen the front sway bar (if adjustable), or set the coil-overs at the front to a softer setting, by one increment. Just remember Tein have probably based their "recommendation" on a stock car, as Japanese owners do not typically replace sway-bars and bushes. So if you have sway-bars, bushes, etc, this will require you to experiment with the settings of the coil-overs and adjustable bars.

Ideally you should have a 10mm differance of the height (from centre of hub to arch) from front to rear. R33 Skylines have a higher arch at the front wheels to allow more clearance while turning. Having the same height clearance all round actually sets the front lower than the back. Ideally the measurements are: F:350mm R:340mm. But if you are happy with the fronts at 345mm, try lowering the rear to 335mm, this will require you to check you alignment again.

scathing Grand Master

scathing

Posted
Posted

Do you have an EDFC? And is the front behaving the way you want it to?

I'd recommend stiffening the rear sway bar up a bit, and giving it a go. If its close to the balance you want, you can then use the EDFC to fine tune (especially in wet / dry conditions). If its still understeery, stiffen the rear bar some more.

I'm using Flex+EDFC in my Z33 and I've got my adjustable bars set to full hard front and full soft rear (its too taily with hard all round). I still get the steering response I want from the stiff front bars, and I use the EDFC to adjust the dampers to fine tune the balance.

nuffsaid Veteran

nuffsaid

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Posted

I like the slightly nose down look as opposed to the bum down look, happy with the ride height at the momment, but thanks for the suggestion.

I have experimented with the front stiffness setting, but found 4 to be the most suitable in terms of dampening on rough streets. It has fairly good control on rough and bumpy roads, the rear is different though.

No EDFC sorry, very expensive, and expensive to install haha

I will set the rear bar up one level and see how I go.

Note: id much rather the car oversteer a tiny than understeer as understeer gets quite scary.

Sydneykid Grand Master

Sydneykid

Posted
Posted

The front at 345 mm is too low, raise it up 5 mm

The rear at 345 mm is too high, lower it 5 mm

Stiffen up the rear bar

Stifen up the rear shock settings

The front bar is already on full soft

How much toe out do you have on the rear?

Does it still have HICAS?

:P cheers :P

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