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if they are the RE540s they are really, really old. they were superseded by RE55s a looong time ago. that could be part of the problem, they are probably pretty hard so they will still give good 'feel' but not near as much outright grip as they should (hence you won't be getting near as much body roll as you normally would).

try again with your next new set, and on the first track day borrow someones heat gun or pyrometer for a session or two and as mentioned above split the tyre into 3 segments (inner, middle, outer) and measure the temps. you will soon see how it's working the tyres.

the other question is have you done many road kms on them? cause that will definitely wear out the insides even with 'just' 2.5 degrees neg.

if they are the RE540s they are really, really old. they were superseded by RE55s a looong time ago. that could be part of the problem, they are probably pretty hard so they will still give good 'feel' but not near as much outright grip as they should (hence you won't be getting near as much body roll as you normally would).

try again with your next new set, and on the first track day borrow someones heat gun or pyrometer for a session or two and as mentioned above split the tyre into 3 segments (inner, middle, outer) and measure the temps. you will soon see how it's working the tyres.

the other question is have you done many road kms on them? cause that will definitely wear out the insides even with 'just' 2.5 degrees neg.

Hey Baron,

I did a DECA on them, about 30k's and had no noticable wear. Car was trailered down.

Car has done another 30-40 street k's since that track day as it's not really street friendly in looks or mods, street reg'd yes, driven rarely though.

I'm thinking see how we go with the next set of rubber, I'm just not keen onthe idea of learning that I have a bad setup while chewing out new semis.

Pyrometer will tell me the inside egde is hot sure, but then what? I still need some idea of what requires adjustment.

Might have to get DMS to align it at that point.

Castor should not change with more or less camber. Correct me if I'm wrong people.

Dane. +2mm rear = drift?

Not sure yet Russ, but will be interesting to see. It didn't feel super loose in the rear end at Sandown at all, but it was pretty damn slow driving so I can't tell. I was wary of it too, but I explained my issues to Traction Tyres and they recommended this so we'll see!

Dan: Will be interesting to note the difference the reduced castor makes. My castor brief is 'as much as possible'...

8kg (450lb/in) is very stiff in an S13 for grip work.

I started with 9/7kg (500/390lb) springs that were in the car when I got it - absolutely hopeless. Far to stiff for semis. Car was totally unable to cope with bumps. Dropped down to 7/5.8kg (390/325lb)and it was better, but still very hard. Car would almost skip over bumps on the high speed sweeper under the bridge at Lakeside. I'm now down to 5.8/4kg (325/225lb)which is getting pretty close to the money in my opinion. Its certainly not soft.

I run far more camber than you and a bunch of toe out and have no inside edge wear. My vote goes on the old tyres misleading you as well.

Edited by hrd-hr30

Some very good food for thought there.

Thanks as always guys, appreciate the time taken to respond.

Has my question been answered? Not entirely but I do have more things to consider and am more aware of the factors at play so we're moving in the right direction. :(

EDIT: Coz I'm the mad typo king uleh~

Edited by ActionDan
What Jamie was saying is that more caster = mroe neg camber through cornering = more load on the tyre shoulder, more heat, more wear etc.

Yes that is correct. Dynamic camber is a good thing so you're gettting more camber when you need it and not when you don't (braking).

Yes that is correct. Dynamic camber is a good thing so you're gettting more camber when you need it and not when you don't (braking).

The thing you need to be carefull of is the hype the drift %#^$ers come up wtih in regard to castor. Yes it helps. But at small angles and in small amounts of lock it is far less influential than people think.

The thing you need to be carefull of is the hype the drift %#^$ers come up wtih in regard to castor. Yes it helps. But at small angles and in small amounts of lock it is far less influential than people think.

Yeah. Castor is good for drift cos it helps the steering return to centre when doing mad snakies. :D

Drift can get out...

Cmon man. Drift is sik!

  • 3 months later...

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