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Massive Understeer At The Track, What To Do?


xr_velocity

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  • Member For: 18y 26d
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36psi hot is a bit high, I run 30psi in the front and 28psi hot in the rear and the tyre contact is almost perfect. I could probably drop 1-2psi in the front.

I will drop the pressure again next time. Thanks.

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  • Member For: 16y 11m 3d
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See what I mean?

Glad that the front end grip has improved and now has sufficient capability to actually control the front end.

I would say that the rear end grip has actually marginally improved, as it has had to improve to keep up with the better front end.

Have a close look at the tyre contact patch on the rear. That is how it should be for a tyre to deliver maximum grip and wear.

Without the rear bar, it will not hammer the outside edge at all.

It would be good to be able to get that same contact patch on the front, but that would mean new UCA's and mounts.

Their pivot point really does need to be moved lower,

The hot operating pressure is the one to look at.

I would still go with a spring rate halfway between std and the 520's rate.....IMO.

Edited by Smoke them tyres
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I already have the springs, I get it all at cost price thanks to a brother that works at Burson and a mate whose family owns a car parts store. If they are a step backwards I can always ebay them and get some new ones, will only cost me a couple of alignments anyway. My old Lovells will be going on ebay, someone will like the very low look.

The rear end is definitely improved, it was a lot easier to steer with the throttle without the rear bar. The feel from the rear end is very good, it's progressive, no sudden movements, just linear slides on the throttle. It is still far superior to the front end grip. Though the front is still too soft, under brakes it unloads the rear tyres too much taking away some grip. The rear end was moving around a little braking from say a right hander into a left hander. That sort of movement unsettled the car a little.

There is still much more to be gained in the front. The outside edges of the front tyres no longer exist! They were scrubbed away once the tyres got too hot, combine that with not enough front camber and say goodbye to those tyres. The next track day is in November, so I have some time to get the front springs in, a camber kit and an engine oil cooler....the engine oil overheats in the afternoon on a 21 degree day, mornings are OK, I can go the whole 20 minute session. Other than the engine oil temp, the rest of the car has fared well in terms of heat. I will also be wrapping the turbo dump pipe in some of that heat tape to try and keep the engine bay temp0s down a bit and to prevent and items surrounding the dump pipe from melting.

Just a note to others out there about engine bay heat, there is a red battery wire that runs along the chassis rail below the turbo, this will melt through the plastic exposing the live wire.....wrap this in some heat reflective stuff.

The Ferodo DS2500 front pads are brilliant compared to the stock Brembo pads! The Brembos were good and reliable at the track but do not have the stopping power of the Ferodos, they did last 3 track days, a couple of Powercruises and about 20000km so not complaining. The Ferodos took two sessions to bed in. While bedding in I had to take it easy, initial bite was great, but once they got heat in them they lost any ability to create friction. But once the third session came about, they were awesome. Where I would normally brake hard with the Brembos, I would have to back off the pedal with the Ferodos because they kept making the ABS go off. I have to get some stickier tyres to take full advantage of them. Coming into a 150kmh + corner the ABS would go off meaning I would have to back off the brake and get back on it again. Turn 2 is hard on brakes, hit it at bout 165kmh and have to get down to about 60 or 70 for the hair pin. I overshot that corner thanks to the ABS a couple of times.

I also have the PBR 328mm rear brakes on now with Bendix Ultimates. They do the job, at least they did not crumble apart like the old QFM A1R pads on the original solid disks.

Edited by xr_velocity
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My thoughts on Eastern Creek track.....brilliant track! Plenty of fast sweeping corners and tight technical turns as well. It is a great track to learn at as you face just about every scenario possible in one lap. It takes some time to learn it though.

At the moment I am loving turn 4, a sweeping right handerat the bottom of a down hill, I can get about 1.2G through that one, it has a tricky exit where you have to power out and get yourself set up on the opposite side of the track under brakes. A lot of people have come unstuck on that corner and hit the concrete! They really need some kitty litter there.

The other is turn 11. Coming down from about 140 into turn 10 a slight right hander, having to brake and set yourself up on the far right to throw the car into turn 11, a nice flowing left hander that you can take deceptively quicker than what it looks like you could. Plenty of grip there.

One area of the track I don't have the knackers yet to master is turn 1! I can see the fast guys are on the gas all the way down the straight and brake into the corner, whereas I brake well before the corner from about 210- 215 and roll into it at about 150. With a bit more practise I will be able to do as they do, but for now my dacks have stayed clean and the car in one piece! Once I have more confidence in the car and how it reacts, it will change my confidence levels. In this initial setup phase I am still very cautious.

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My thoughts on Eastern Creek track.....brilliant track! Plenty of fast sweeping corners and tight technical turns as well. It is a great track to learn at as you face just about every scenario possible in one lap. It takes some time to learn it though.

At the moment I am loving turn 4, a sweeping right handerat the bottom of a down hill, I can get about 1.2G through that one, it has a tricky exit where you have to power out and get yourself set up on the opposite side of the track under brakes. A lot of people have come unstuck on that corner and hit the concrete! They really need some kitty litter there.

The other is turn 11. Coming down from about 140 into turn 10 a slight right hander, having to brake and set yourself up on the far right to throw the car into turn 11, a nice flowing left hander that you can take deceptively quicker than what it looks like you could. Plenty of grip there.

One area of the track I don't have the knackers yet to master is turn 1! I can see the fast guys are on the gas all the way down the straight and brake into the corner, whereas I brake well before the corner from about 210- 215 and roll into it at about 150. With a bit more practise I will be able to do as they do, but for now my dacks have stayed clean and the car in one piece! Once I have more confidence in the car and how it reacts, it will change my confidence levels. In this initial setup phase I am still very cautious.

I've done a 3 track days here now in my FG and agree it is a great track. Went from 2min01 first time (stock power, Front Brembos, king springs) to 1min55 3rd time there (285rwkw, bigger front rear bars, 600lb front springs, koni red shocks, worn out r888's). Expecting a 1.53 next time depending on conditions and will be using Hankook grooved Z214's on the rear in 245 and a new front camber kit. Found my Toyo R888's to make the biggest difference to time. Tyres are THE most important thing for track set up. Biggest bang for buck to improve every aspect of handling/braking/power down etc. With Semi's you will knock off 3 seconds instantly.

I have been in the car with 3 instructors now, plus some great tips from Rosie (I think who laps his Roof Racked Taxi through here in 1.48's-49's!). At turn 4, I was braking too early. Because it is uphill a bit before turn in, slam on the brakes at the 50m point (won't unsettle the car too much) and don't enter the turn too far to the left before turn in if that makes sense.

You will never get a 2 tonne car through turn 1 flat out. You have to ease off, don't turn in too early and coast through the first part of the turn to settle the car then power on hard through the exit.

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My experience has been that the only thing to gain from the camber kit is on which side of the chassis the mount nuts are on...std= engine bay, kit= wheelwell.

The pivots in the kit are exactly the same as std, so the is no real benefit to them. Wasted $.

-buy the Fulcrum mixed shim kit so that all is required is to loosen the UCA mounts and slide the shims in and out for adjustment. The std shims have holes only and require the UCA mounts to be fully removed for adjustment. The std mounts have the nut on the engine bay side, but this is not a big issue with the 4L.

-I have dialed -2.5 degrees of camber into mine at the front with 3mm (1/8") toe in per side. And a "reasonable" amount of caster.....initial camber is more beneficial than caster, as it is there from the start. If you try to go for too much caster, you will start to lose camber. This is due to the D shape of the UCA. Shimming the front mount effects caster the most, shimming the rear mount affects camber the most.

-the rear I have left as std (apart from the nil swaybar and a bush or two)......it just plain works right out of the box once that is done.

Another reason that I would not go too stiff on the front......the stiffer front springs will not allow the suspension to compress as much, thereby limiting/lessening how the UCA combats the positive camber gain from body roll.

If you can't get that initial camber PM me.

Edited by Smoke them tyres
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