That's why we like tweaking! Interestingly, one of the first things Kenny Brown always said was "throw away the rear sway bar and lower the rear roll center." One would think it would push like a pig, but if it works, it works.I look at it like;
Let the car rotate around the roll center without reducing load on the inside tire. This is why I don't typically run a rear sway bar. (never say never though)
Its job is to add load to the outside tire by taking it from the inside tire and adding that spring rate in with the total roll couple. Seems counter productive to me.
With a high roll center you share the load more equally but load transfer from body roll is expressed at the contact patch rather than around the roll center.
Too high and the car just skates. Others like big rear springs to keep a balanced chassis. But again, too much and it skates and as a nice bonus you sacrifice forward bite.
I like low roll centers and soft springs. I'll deal with the body roll and understeer as long as I continue to beat the next guy off the corner.
However, I continue to test and try different approaches and combinations in the quest for lower lap times....who knows what I might find.
And that's the fun of it....right?
Wes,Agreed on all counts...at least in theory. What's weird: accounts of how this setup works on real cars leads me to believe there's more going on than we may realize. I'm growing more convinced that the extremely low roll center benefits a live axle car more than an IRS because live axles seem to be more sensitive to the jacking effect with above-ground roll centers. Maybe the corner exit bite from minimizing jacking the inside rear wheel outweighs the loss forward bite from stiff(er) rear springs. Going back to theory, however, if both rear wheels are more evenly loaded (from the low roll center), then the rear diff can be "looser," which also reduces understeer.
All food for thought!
Yes, I have been. The car goes up on my lift after each event, and to do a full inspection, including the welds on the lower arms. I may opt to install the BMR upgraded arm, but I'm also considering fabricating full gussets and welding them in place this coming off season. Jury is out right now. Thanks for the heads up!Keep an eye out for the BMR A-arms. They should be on your track day inspection list.