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Croustibat · 03-22-2016, 04:09 AM

I am using the same tyres and dimensions (perfect wheel + tyre diameter equivalent for stock), but with a 300hp ca18det. They could easily cope with at least 50 more hp, so stock KA is not going to embarass them... I think you could do with skinnier tyres, they are going to rob a lot of power.

I suggest you do whatever you can to remove bump steer and toe steer first. Static geometry makes no sense unless the dynamics are correct. If your toe gain is like 5mm per cm of travel, you will never control the car correctly.

From experience, you cannot remove toe steer (at the back) without some binding in the rear if you use less than -2° camber (-1.5° is "less than -2°" in that figure).

This is corrected by setting rear tension rod longer than stock. You have to find the correct length by yourself, it depends on how much the car is lowered. Put the car in the air, unbolt the rear ARB, remove coilover, make the suspension go up and down from its central position, and trace the toe curve. Add a couple millimeters and do it again until you get what you want (i like slight toe in on compression, nearly no toe change from a bit of compression to full droop)

You need aftermarket steering rack rod ENDS to correct some bump steer (at the front), but that depends on the rules you have to follow. Honestly i suggest a front drop knuckles and arms set. As much as you can correct the rear suspension setup by changing arms length, you cannot do that at the front.

If you don't, you don't want a lot of caster with a shorter tension rod and the stock FLCA as the bush will bind. The best way to set caster is with 3D coilover tops anyway. I'd say that bush is the first to replace with a ball joint. If it is stock, it must he shot anyway. Same goes for the tension rod.

I would add some camber front. I think i was running -2.5° last event (i have no arb but 10/8 springs) and my front tyres are more used on the exterior.

Toe settings: i like a little toe in rear (total approx 4 to 8mm) and a little toe out front, to get stability under braking and reduce understeer on corner entry, but that is up to the driver's way of driving, and how much he worked on correcting toe changes on suspension movements.

03-22-2016, 04:09 AM	#6
Croustibat Nissanaholic! Join Date: Aug 2011 Location: France - Toulouse Age: 41 Posts: 1,851 Trader Rating: (0)	I am using the same tyres and dimensions (perfect wheel + tyre diameter equivalent for stock), but with a 300hp ca18det. They could easily cope with at least 50 more hp, so stock KA is not going to embarass them... I think you could do with skinnier tyres, they are going to rob a lot of power. I suggest you do whatever you can to remove bump steer and toe steer first. Static geometry makes no sense unless the dynamics are correct. If your toe gain is like 5mm per cm of travel, you will never control the car correctly. From experience, you cannot remove toe steer (at the back) without some binding in the rear if you use less than -2° camber (-1.5° is "less than -2°" in that figure). This is corrected by setting rear tension rod longer than stock. You have to find the correct length by yourself, it depends on how much the car is lowered. Put the car in the air, unbolt the rear ARB, remove coilover, make the suspension go up and down from its central position, and trace the toe curve. Add a couple millimeters and do it again until you get what you want (i like slight toe in on compression, nearly no toe change from a bit of compression to full droop) You need aftermarket steering rack rod ENDS to correct some bump steer (at the front), but that depends on the rules you have to follow. Honestly i suggest a front drop knuckles and arms set. As much as you can correct the rear suspension setup by changing arms length, you cannot do that at the front. If you don't, you don't want a lot of caster with a shorter tension rod and the stock FLCA as the bush will bind. The best way to set caster is with 3D coilover tops anyway. I'd say that bush is the first to replace with a ball joint. If it is stock, it must he shot anyway. Same goes for the tension rod. I would add some camber front. I think i was running -2.5° last event (i have no arb but 10/8 springs) and my front tyres are more used on the exterior. Toe settings: i like a little toe in rear (total approx 4 to 8mm) and a little toe out front, to get stability under braking and reduce understeer on corner entry, but that is up to the driver's way of driving, and how much he worked on correcting toe changes on suspension movements.