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Suspension Set Up

Ronin 09
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Ronin 09 Grand Master

Ronin 09

Posted
Posted

Hi guys

Yesterday I went to Sandown for the day and have some queries with the handling.

The car seems to be nosing over and pitching a lot to the front right, and really chewing out the outside of the tyre. Also not great on turn in, and getting a bit of understeer.

Any suggestions for set up?

The current list of parts / settings are as follows:

Ohlins adjustable shocks

F 8kg R 6kg springs

Ride height 355/350 (ish) front and rear

Whiteline front and rear bars, set on mid for both

Front toe / camber / castor - 0 / 1.5neg / 5pos

Rear toe / camber - 0 / 0.5neg

Is it under damped?

Thanks

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BHDave Grand Master

BHDave

Posted
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I'd be inclined to say more camber front and rear, min 3 front 1-1.5 rear as it sounds like you are rolling over on the outside wheel a bit

I like toe out on the front but i have a gtst and don't know if it translates to gtr. It certainly improves turn in.

What's it like on corner exit? oversteer or under? Possibly tighten the rear bar if it's understeering. That should also improve turn in

Roy Grand Master

Roy

Posted
Posted

Give me the car for the Cup Day sprint :rolleyes:

I think a lot of the problem would be in the front ride height. There seems to be a trend with quick GTRs where their fronts are higher then rears. Also, maybe tray a track like Winton before getting too worried about it using the outside front right tyre. its naturally the case at an anti clockwise track like Sandown...but abit more camber would not hurt.

Thing is due you want it to be a nice road car that uses its tyres well, or a track car that looks after tyres at the track but eats tyres on the steet? Its hard to get a good compromise

Ronin 09 Grand Master

Ronin 09

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Posted

probably want it to be a nice road car, but it does so few kms it's not a huge issue with camber tyre wear etc.

but still want it to be fun around a track at the same time

looks like the perfect setup - street and track friendly... it's the mirage

BHDave: thanks for the advice - my suspension guys reckon i should stay away from toe out for the moment b/c I'm a track spastic and the car can get twitchy. Corner exit it's a little understeery, probably a bit too much rear grip, it feels like it is pushing a bit

Rich: doesn't softening the front bar increase the roll and incidence of falling over the front right? thanks re castor - see above - I'm a spastic

I'm trying to get a pic of it coming onto the main straight to see how much it is pitching

Beer Baron Grand Master

Beer Baron

Posted
Posted

yeah if you want it to be nice on track you need to man up and go with:

front toe out. at least 1mm each side, more if you are brave

front neg camber. 3 degrees will be nice.

soften front bar

stifen rear bar

bit more rear neg

and start playing with your endless combos of bump and rebound damping.

but it will be pretty average on road (unless you are well up it).

Beer Baron Grand Master

Beer Baron

Posted
Posted

he just means late apex. we often get sucked into turning in to early. you really need to wait...wait...wait.. TURN IN NOW!

also with the GTR it really likes the slow in fast out approach. going in too hot means you will be moving around a lot under brakes and probably still trailing a little brake at turn in which is not good for business. I am majorly guilty of all these faults...and more.

so getting the thing slowed up enough before the corner, then tip it in nice and late, then on the power early may cure it. sometimes adjustment in driving style can negate some of the need for suspension change.

Duncan Grand Master

Duncan

Posted
Posted

yeah mate. We of course aren't allowed to change anything on the race car except ride height, toe and tyre pressure - so as a result I always look at how I am attacking a corner first instead of trying to change the suspension.

gtr is a heavy car, has great traction and good power. All that together means brake hard, balance mid corner nice and smooth, then on the gas hard and early for corner exit, let the 4wd pull you out (4wd controller really helps a 32)

thats if the problem is mid corner and exit understeer. If its understeer on turn in try a little front toe out - it will make it feel a little twitchy but nothing dangerous. Rear toe out is a different story it can be exciting

tacker Mentor

tacker

Posted
Posted
he just means late apex. we often get sucked into turning in to early. you really need to wait...wait...wait.. TURN IN NOW!

also with the GTR it really likes the slow in fast out approach. going in too hot means you will be moving around a lot under brakes and probably still trailing a little brake at turn in which is not good for business. I am majorly guilty of all these faults...and more.

so getting the thing slowed up enough before the corner, then tip it in nice and late, then on the power early may cure it. sometimes adjustment in driving style can negate some of the need for suspension change.

Yep i have the same problem so going to try a little more agressive settings, different shocks, different bars, 350mm hight in front 340mm in rear. And if that dont work another pilot.

King of understeer signing out.

post-28646-1193803177_thumb.jpg

tacker Mentor

tacker

Posted
Posted

LOL here we go again.

Not the best pic but it is a banked corner at 16 degrees. I did purchase neg 5 degree cusco upper arms or so the package said?

Still it was just a mixed and matched set of suspenssion componants and car was to low and body roll was at an all time high.

going to correct that and be free of understeer forever :-) and yep damn pesky GT2 porker they are quick and light, handle well look good, cost grillions, chick magnet and i am going to spank it next time out :P

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