Attached is the alignment sheet for my '08 MCS lowered with H&R Street Performance Coilovers. Need forum suspension experts to let me know if the spec's look ok or if I should make some changes to ensure good tire wear and handling? Mini still feels a bit darty mid corner. Thinking that the camber difference between the front strut/wheel assemblies and the overall difference in camber between the front and rear might not be optimized for consistent handling? Comments?

 

I think you'd be better off with front negative camber in the 2-2.5 degree range.

 

Only if he's running a strict track car that has a ton of body roll. Otherwise, about -1.0 degree is fine for a fast street car.

Just based on the alignment sheet I'd suggest zeroing out the toe in back, but you're already saying it's "darty" mid-corner, so in that case I wouldn't recommend that, or increasing negative camber in front. Your alignment looks pretty tame to me, not sure why it would feel darty at all unless there's a problem somewhere. H&R coilovers use a really REALLY heavy front spring with a barely-stiffer-than-stock rear spring, meaning the car will now understeer like crazy; also hint it wouldn't be darty in corners. The one thing the H&R coilovers would do is improve transition quickness, meaning when you're changing lanes on the highway it'll feel really quick and planted, but in actual corners it'll understeer. Can you describe the concern in more detail?

Thanks,
Ryan

 

[quote=Ryephile;2227193]Only if he's running a strict track car that has a ton of body roll. Otherwise, about -1.0 degree is fine for a fast street car.

Just based on the alignment sheet I'd suggest zeroing out the toe in back, but you're already saying it's "darty" mid-corner, so in that case I wouldn't recommend that, or increasing negative camber in front. Your alignment looks pretty tame to me, not sure why it would feel darty at all unless there's a problem somewhere. H&R coilovers use a really REALLY heavy front spring with a barely-stiffer-than-stock rear spring, meaning the car will now understeer like crazy; also hint it wouldn't be darty in corners. The one thing the H&R coilovers would do is improve transition quickness, meaning when you're changing lanes on the highway it'll feel really quick and planted, but in actual corners it'll understeer. Can you describe the concern in more detail?

Yes, freeway lane transitions are quick. Straight line stability is good. Today, I drove the Mini over a deceasing radius turn that I had previously driven many times in my R32, and overall the Mini felt very planted until I hit the tightest section that also had a few bumps; at which point, with the suspension loaded up, the Mini did not want to hold a consistent line and darted off-line. Felt like the front and rear are not synched up. I'm starting to believe that the suspension bushings are too soft and that maybe mid-corner camber and toe changes are causing the instability? Having said that, at this point, it seems the stock set-up is more predictable under load.

 

You shure your not bottoming out on a the outside front?

 

The H&R coilovers use a front spring about twice as stiff as the stock spring. I'd guess he's not bottoming out, but experiencing those very stiff front springs, where the setup doesn't have proportionally stiff rear suspension to maintain chassis balance.

The R56 has absurdly soft front control arm bushings that cause nasty steering ambivalence when deflected [compared to the old gen MINI]. That said, that bushing deflection will only change caster, not camber or toe. The MINI actually does a great job in keeping it's alignment stable throughout suspension stroke.