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R TUNE Mentor

R TUNE

Posted
Posted (edited)

Strut brace

RSR springs beileved to be Ti2000 HD 40mm～35mm lower 5.50kg/mm front 25mm～20mmlower 4.50kh/mm rear

Stock rims.

Problem.

understeer, can’t get the back to brake traction.

Hand brake is tight but wont lock properly

Basically took the car to a motorkhana and drift day.

Biggest problem I found was understeer and trying to get the rear end to break out. If I did it was hard to catch it and usury ended up spinning.

I don’t think the front end angle (lower control arm being upwards) helps at all to.

I know sway bars will help but at which end.

I’ve inc some pics. The small gap between tyre and guard is the front.

first is front

2nd rear

post-32868-1272246180_thumb.jpg

post-32868-1272246298_thumb.jpg

post-32868-1272246468_thumb.jpg

Edited by redliningr31 skyline
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GTR-N1 Grand Master

GTR-N1

Posted
Posted

Usually, replacing the rear sway bar with a thicker one + heavy duty linkages will help reduce u/steer.

I'd get an inexpensive safety check done by Repco/Jax/Pedders or other without commiting yourself to them and ask lots of Qs as well as get permission to look at everything underneath. Pick their brains!

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Daewoo Enthusiast

Daewoo

Posted
Posted (edited)

Was the motorkhana on dirt???

Plough understeer and snap oversteer (where it goes from plough understeer to massive oversteer) is always a problem for big heavy cars with single spinners... I probably wouldn't recommend a thicker rear sway bar with a single spinner, 'cause it will only make the inside wheel spin more...

Adding some negative camber to the front end will probably help... you can cut the lower control arms and lengthen them by 10mm per degree of neg required... totally illegal for the road if that concerns you... you might be able to get some adjustable pins for where the control arm bolts to the front cross member... but they can usually only give you one degree...

Maybe adjustable castor rods so you can get some additional castor as well... and a little bit of toe out on the wheel alignment...

The drift guys will be able to tell you the best settings, but I run 2 1/2 degrees negative camber, 3 degrees of castor, and 2mm of toe out on my 1600 on dirt...

I am bloody hopeless at motorkhanas, and always seem to be understeering everywhere... I always complain about the set-up and then someone who knows how to drive gets in and has it slidding perfectly everywhere... it might be your driving style like it is mine... don't touch the handbrake until the car turning, because it needs the momentum to make it slide out... otherwise all you are doing is taking one hand off the wheel that would be better employed grabbing more lock... Same same with the throttle pedal... get the car turning then stomp on it, rather than too early...

Cheers,

Daewoo

Edited by Daewoo
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R TUNE Mentor

R TUNE

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Terry, The car will be getting an aliment with in the next tw week's.

Daewoo,

track was tar but poor condition. i.e alot of loose tar every were as it was done at the paddock are of hidden valley race track.

The line has the factory LSD in it and it works.

front is pretty low and has some neg camber allready. as mentiond above the LCA sit at upwards angle

By the end of the day i was able to controll the car and get it to slide. but it still would either plough understeer or snap over steer, i just adj to catching the slide and was able to hold it.

post-32868-1272271285_thumb.jpg

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Duncan Grand Master

Duncan

Posted
Posted

I suspect you can't change the slow speed handling much without dramatic changes.....try driving style instead.

turismo is probably the right man to answer because he runs rings around me (not to mention he is the australia motorkhana champion)....but...

clutch kicks to get the back around on entry! handbrake if necessary

weight shift set up really early so the rear wants to break away.

stay on the brakes to keep the weight on the front wheels so the thing turns in.

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blind_elk Grand Master

blind_elk

Posted
Posted
as mentiond above the LCA sit at upwards angle
Then it's probably too low. It probably sets up +ve camber, which only becomes more +ve as you transfer weight onto that corner. And +ve camber is real good for understeer.
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R TUNE Mentor

R TUNE

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Then it's probably too low. It probably sets up +ve camber, which only becomes more +ve as you transfer weight onto that corner. And +ve camber is real good for understeer.

Dun, she is auto so no clutch kicking at this time.

handbrake just wont bite.

Thats what im thinking, plus roll center would be farked. so new springs some time soon.

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Roy Grand Master

Roy

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Posted

Ok, i think go with the basics. Have you got the same brand and wear level on all 4 tyres. What are the tyre pressures you are running? As for motorkhanas, yes they can be tricky in a std car....but I think they also happen to be the best car to learn how to drive using the dynamics of the car.

So as Duncan said, use the weight transfer to steer the car. With std shocks and lowered springs you will struggle with roll understeer, lift off oversteer etc and unless you are quick with steering tank slapper action....but there is the challenge of punting the car.

Std susp and understeering. Make sure you have 36psi in the front and try 42psi in the rear. Then, carry plenty of brake when you are starting to turn the car....forget that you are in a rwd car and want to turn it on the throttle, pretend you are in a FWD car and carry the brake for as much of the steering you can. Then when you get on the loud pedal, do so smoothly but quickly so as not to unweight the front too much.

I quite enjoy punting ill handling cars, i suppose its a good challenge, and probably part of the reason my car was all over the shop for so long :P

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joeyjoejoejuniorshabadoo Grand Master

joeyjoejoejuniorshabadoo

Posted
Posted

also you could try to feint it a little...

say you are gonna turn right at a cone, as you approach it turn left slightly so that the COG shifts a lil to the left... then as you snap it to the right hit the anchors. this should start a pendulum effect and slide the back out nicely.

keep the tyre pressures up in the rear and down in front too

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GTS4WD Grand Master

GTS4WD

Posted
Posted

Wheel align the car propery too.

Toe out at the rear and the front.

TO out the front will cause it to dive in, TO at the rear will cause it to oversteer.

As said before, tyre press is good too. increase the rear press to lessen the grip.

Invest in good rubber for the front.

Turn in under brakes, keeps the weight on the front, pushes the rubber on the road.

Feint before corner

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Duncan Grand Master

Duncan

Posted
Posted
Wheel align the car propery too.

Toe out at the rear and the front.

TO out the front will cause it to dive in, TO at the rear will cause it to oversteer.

As said before, tyre press is good too. increase the rear press to lessen the grip.

Invest in good rubber for the front.

Turn in under brakes, keeps the weight on the front, pushes the rubber on the road.

Feint before corner

I agree with all of that for motorkhanas....but just wanted to mention that I would never recommend rear toe out on a street driven car. Its the sort of thing that makes you end up backwards in a telegraph pole on a wet night. will definately help on the skid pan though.

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R TUNE Mentor

R TUNE

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I agree with all of that for motorkhanas....but just wanted to mention that I would never recommend rear toe out on a street driven car. Its the sort of thing that makes you end up backwards in a telegraph pole on a wet night. will definately help on the skid pan though.

Cheers guys

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