What front diff are you using?

Wavetrac but ive had it for years. the car only started cornering like it does now after i put SSB front uprights in and SSB offset caster top hats

i finally had another few runs with the ssb uprights. they weren't timed so i can't comment on how much faster it went, but with the uprights + back to 17x9.5 in same width tires, the car felt a little pushy. a little bit surprising since the old setup was if anything a little too loose. i've got adjustments i can make with the rear bar, but was a little surprised given i've got the rear uprights too, which dallas said makes turn-in pretty crazy. but again every setup is different. hard to measure without driving it on the same track

You did not adjust spring rates?
Dallas suggests that while say typical spring rates on OEM uprights for track may be 12kg front 14kg rear, when employing his uprights, you should increase the spread to 12kg front 16kg rear maybe, or even more in rear (17-18K?).

So adjusting the rear bar will help I think.

I had 12/18k rates and then did uprights and kept 12/18k and the most significant thing I noticed was the rear end didn’t feel as loose with cold tires. I think stiffer rear will help. I did a HPDE on 12/18k and it felt good, then went 14/24k and just felt easier to drive. I haven’t done another HPDE with the higher rates, but I’m on 12/24k now and mainly autox and it’s pretty dang amazing on street tires.

we did 14/20k(softer front bar, stock rear) on meathooker’s “budget build” and he said it felt great on track too with uprights.

Yeah, at the end of the day we have a front heavy car with a weak-ish front suspension design and light rear with great suspension geometry. So you either have to momentum the back around things or ask the rear to do more work via roll rate bias.

I always recommend 50% more rear spring at a min. So 12k would make 18k min rear. 8k/12k would be a pretty decent street/autox rate.

How much would that be in lb?

1 kg/mm = ~56 lb/in
so 10kg = ~560#

Dallas, for benefit of those who may want to continue to use the Dual Purpose Road and Track Evo over bumpy backroads,

What is, with your uprights on all 4 corners, minimum (optimal spread front rear) spring rate that you would recommend, that gives sufficient support to the chassis to be effective on track? On R compound tires. And retain bumpy road compliance. Assuming quality coilover choice.

What is (softest) optimal track focused Evo spring rate with your uprights on all 4 corners? Assuming 2900-3000 pound car.

Thank you

did not adjust - i ran 8/12 before, i run 8/12 now.

u guys all run way too much spring for circuit in my opinion. im 10k/12k and have heaps of turn in. Id suggest something else is out with your alignment if your getting alot of push. What are your other alignment settings, camber. toe, caster, bars and settings on them.

Its either that or your spring rate is out the window big time.

10/12k is like a street car setup man...

Nope, ya'll just run way too low and on mediocre shocks. 10-12k front is about right. More rear spring nets more front grip.

I think the big disconnect is people always attribute any rear movement with too much rear spring. But drive a 2wd car and they'll move around far more and with less ability to catch/correct than AWD. We need that booty moving!

I can chuck a big rear spring at it and see what it does i guess? I just found in high speed sweeping corners with bigger springs the car would oscillate and bounce.

Id be probably the 3rd fastest evo in nz around Hampton Downs circuit now so cant be too far off. happy to give something like an 18k rear spring a go tho?

Since this is a hot spot for a lot of us SSB upright fam... I'm finishing up the install of mine.

I was previously running 3" brake ducts up front with a custom fabricated nozzle at the caliper, but those will no longer bolt up. So I'm curious what you more track-focused track guys are doing for cooling with this setup. I have some GT3 RS air guides I'm going to toss on the LCAs if I can't come up with anything better in the next couple weeks, but something a little more direct-fed would be ideal from my perspective. For reference: I'm stock caliper, stock 355mm rotor, PFC .01 pads, titanium shims, stainless pistons, SRF fluid. Any insight?