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Thanks for the reply and no worries, it did make sense.
One of the things I'd been asking Mark Ortiz about in his newsletter was why I was getting power understeer in the fast stuff but not in the slow stuff. I was lifting the inside rear in hairpins which really helped the car rotate, lots of front end traction, brilliant, but no inside rear lift in faster stuff and figured that's why the car was pushing under power in the fast corners ie too much rear grip.
At the time I was thinking I needed to add more rear roll resistance but was pretty much maxed out on the rear bar. Ortiz had said that the bar was the bigger governor of how early/high the inside rear would go compared to springs so I couldn't understand which way to turn. In my mind adding more rear spring would add more rear roll resistance (I was worried way to much relative to the front) but probably do little more for lifting the inside rear. He advised to go stiffer on the rear bar. I was looking into boxing the rear beam when I had a light bulb moment...
it actually ended up having more to do with the intrusion of the ESP than anything else. Firstly I went to Yoko A050 R specs. This gave me the mechanical grip to be able to run with the brake modulated "diff" turned off. I'd been getting awful mid corner throttle cuts that would dump the power suddenly - the front end had been on line and gripping just fine anyway (but a sensor disagreed due to a slight amount of power wheel spin). Also when I had been getting this drama previously I was on softer compound fronts than rears. I think I was getting too much rear slip and in the high speed stuff when the ESP was all keyed up and ready to intrude (but wouldn't in the slow stuff) it was reading the situation as life threatening oversteer and braking this wheel and that and straightening the car up on me. So now that I have more grip that is consistent all round, I'm not getting that problem anymore.
Now my problem is more what you alluded to. I'm coming around to the idea that a bit of rear squat is not such a bad thing like you said. Ortiz seemed to say that too. I think the front is the drama now. I have nearly 5 degrees neg caster but only 3/4 degree neg camber (and hub geometry that tends to eat up that neg camber very quickly apparently). So in the tight stuff I'm still all good due to lots of caster induced corner camber, but in faster flowing stuff without much steering lock I simply don't have the camber. I recently did the Bathurst, Mt Panorama hillclimbs and some of the fast stuff across the top of the mountain between the walls got very hairy as the car wanted to push wide under power. I was just loosing so much time waiting on the throttle before I could plant it.
In the interest of preserving what little camber I have I run the car at a 'lower control arms level' ride height to keep the RC up, and run 50 profile 15's so the tyres aren't too camber sensitive. I have enough money for only two things 1. fit adjustable camber tops, or 2. fit bilstein B8's or koni yellows. Not both. I honestly don't know which - either better damping or just a bit more negative will give me the best gain. When I do either 1. or 2. ill be fitting slightly stiffer springs at the same time for a bit more camber control too.
With my rules I need to be on road legal tyres, suspension is free in terms of bolt on componentry but I can't modify the chassis. I can fit bolt on braces but not weld in ones without being classified up to type 2 or type 3.
So what do you think - better front damping with minimal neg camber, or more front camber on OEM sachs damping.
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