grubinski

2nd power ...

https://en.wikipedia.org/wiki/List_o...nts_of_inertia

DavidNJ

You're right. I was probably using the density, ρ, rather than mass, m, and just looked at my equation in MathCad without fully engaging brain.

Rhop101

I'm on 225/255 RE71r tires, with the Karcepts .188" wall on hole 5/6. That would be equivalent to 4/6 on a .25" wall. I'm not fast enough to comment if it is faster or slower than another setup. I can say it doesn't wash out in sweepers and remains responsive in slaloms.
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Cool you really like a stiff front bar. Brian Karwin really likes his higher rate front bar of course he's in str but Ryan had Michelle's car running 2/6 .25" wall with 245/255 RE71Rs. So that was my starting point but I'm running 225s up front so I assumed I could only support less bar.

I'll be doing a test and tune in a few weeks so I'll try out some different things then see what I'm fastest with. Maybe I'm too worried about somehow turning the s2000 into an understeering pig

Kevdogs2000

what kind of alignment with that bar? i am going in between the gendron and that bar.

DavidNJ

The rule of thumb in the Street classes (B/Street for non-CRs) is as much front negative camber and positive caster as possible. That should be about -1.9° front camber and a bit over +7° front castor IF the front adjustment bolts aren't frozen and the front subframe is still centered. The fix for the first is cutting through the bolts with a Sawzall or hacksaw. The subframe bolts can be loosened and the subframe recentered; the manual says the bolts can only be used once and should be replaced. I'm limited to -1.7° because of a stuck adjustment bolt.

In the rear there is less agreement on camber. Numbers range from -1.5° (the stock setting) to -2.5°. There is also no real agreement on toe, but most seem to be using very little toe.

The Gendron and Karcepts bars use similar if not the same center section. The difference is in Karcepts' innovative aluminum arms that arch the bolt holes over the links lower pivot and hold the stud letting the link be tightened in the bar with one wrench. It makes for quick adjustment changes and is very innovative. The Karcepts bar may also be a bit less expensive.

Rhop101

I just bought 245/255 re71r Alleggeritas off a car in DC region that has been doing first in B street. Once I get all my control arms replaced since they are all have frozen adjusters. Here are the settings they were using

1/6 .25 wall karcepts bar
Front
Camber: Max
Caster: Max
Toe: 0

Rear
Camber: 2degrees
Toe: 0

RyanDavies

Yep.

Bear in mind that's with stock dampers, and I feel the car could benefit a lot from both a tad more (front) compression and a LOT more rebound.

jeallen

Any rumors on whats coming for 2016 for Autocross tires?

Rhop101

Going into the season so far its still looking like RE71Rs are the tire to beat with the Rival S as a decent alternative. With the Kumhos being the best budget tire. Apparently they came in late last year.

http://www.autocross.us/forums/topic...ires-for-2016/

Rhop101

With the tire shortage this year when time came to replace my tires I got a full set of 245 with the idea of trying them out and if I liked that setup I'd keep them otherwise I have a pair of 255s in order and then the rear 245s would become the front tires for next season.

Well turns out I like the 245 square setup better than 245/255. I don't seem to have any traction loss powering out of a corner and the car seems to have better off throttle rotation so slaloms have become noticeable easier. Some of this might be my switch from 0 toe to 3/32 toe out up front but I'm not convinced of that.

So I'm canceling my 255 order and putting that money toward fixing my frozen left rear LCA so I can get an extra degree of camber on that side. Any others want to chime in on this?