I've talked to the local guys and thought I would ask for some other input
and/or opinions with regard to suspension setup for my car. Before I get into
particulars, let me say that my car is my daily driver and I do a 65 mile
round-trip commute every day. I also have gotten into AutoX, running STX class
currently, and do not have the time/inclination to adjust front toe every time
I go to an event because events are held on Sunday and I don't get home until
late afternoon or early evening. So, I am looking for the best suspension
geometry I can use and still have the car be street and tire friendly.

The particulars of my car are:

2003 MCS
Factory springs, shocks, and front sway bar.
H-Sport competition rear sway bar.
H-Sport lower rear control arms.
RDR Camber plates
Street shoes: 215/45-R17 Yokohama AVS-ES100
AutoX shoes: 205/50-R15 Falken Azenis

So, what would be good front and rear, camber and toe settings, given my
constraints/limitations?

I appreciate any suggestions you guys might have.

 

https://www.northamericanmotoring.co...ad.php?t=36754

 

I concur... if you scroll down, the best all around settings are close to the bottom. Mine's set up very similar and I never touch it on my daily driver/autocrosser/track car!

 

I would add a bit of rear camber to those settings - about 1.5, but it looks good other than that!

 

So you guys are saying:

"
1. Set front camber to 2.0-2.5* negative with 1/16" toe-out
2. Set rear camber to 1* negative with 0" toe.
3. (if you haven't already done so) Set the rear sway to full stiff.
"

and Randy suggests a bit more negative rear camber.

And this is what you suggest for a set-it-and-leave-it setup for both
street and AutoX? This won't result in excessive inner tread wear?

I had read that thread previously but it was not clear to me that the
settings would be good for street and AutoX. The discussion seemed more
centered around the best setting for AutoX and/or track driving.

Thanks in advance for your reply(s).

 

How much highway v. city driving do you do?


Randy

 

Randy, most of my driving is highway on a daily basis (probably 50 of my 65
mile daily commute driving is interstate at 70-75 MPH).

 

You may end up with a bit of wear then.

There is no optimal setting for both - it is a compromise. If you are doing mostly city stuff, you can get away with 2.0 negative camber in the front and 1.5 in the rear. On the highway, probably not so much. The toe settings will still work for you, and on an all out autocross car, I use a total of 1/8 out in the front, so the 1/16 was already a bit of a compromise for me.

Try out 1.8 or so in the front, and 1.3 or so in the rear, with the toe recommended. You should be alright with wear - but keep an eye on it. Then, run more pressure in the front than the rear at the event, and use more rear bar.

Also, I usually use the middle setting on the comp rear bar, not the stiffest. I use the stiffest on cars that have no camber adjustment on the front to get the rear to rotate.

Hope that helps!
Randy

 

Thanks, Randy. A compromise is exactly what I was looking for. I will
go with your recommendations and watch the tread depth.

One final question, I know the front toe goes positive (in) as you increase
negative camber. But, I can't remember the geometry of the upper link
in the rear. Does the rear toe change with camber adjustements there?

 

Yes - if you look at the centerline, the arms effect camber changes after it, so increasing negative camber toes the car in.


Randy

 

Pete,

Your use is similiar to my own. For the last two seasons I've run my MCS at -2.2F, -1.8R with zero toe front and rear. I've got a 80 mile daily commute that is nearly all 50+ mph with a touch of in town stuff.

When the 215/45-16 Azenis are shot the inner surface has about 1/32 tread depth and the outer edge only 2/32. Technically worn on the inner edge, but not enough to impact service life at all. I guess the other part of the equation is that I autocross at least twice a month for 10 months of the year, and drive pretty calmly on the street the vast majority of the time.

Zero toe in front helps the tire wear but will have slower turn-in compared to 1/16 toe out. Despite that, the Mini is not exactly slow to turn in.

Scott
90STX

 

In the rear wheels?

 

Yes, in the rear. The control arms, or camber links, are used to adjust the camber - the lower ones specifically. So, if you make them longer to push the bottom of the wheel out, giving you more negative camber, and the arms are behind the centerline of the rotating axis, then the wheel would be pushed farther out in the rear and farther in at the front, giving you more toe in.


Does that make sense?

Randy

 

Perfect sense. As I said previously, I did not recall the layout of the
rear geometry (specifically where the upper and lower control arms
attached in reference to the vertical axis of the wheels).

Thanks a bunch for the tips and recommendations. Come see us in
Atlanta again. It was great meeting you over at R-Speed that day
with Joseph and his crew, plus Scott and some others in our
AtlantaMINIs group. Are you going to make The Dragon this year?

 

Scott, thanks for the reply and the second opinion. This confirms Randy's
suggestion with real-life experience in similar driving conditions. That tire
wear is prefectly acceptable and remarkably even. Unlike you, we only get
to AutoX about 8-9 months out of the year and in general get 1 SCCA
event per month and a BMWCCA event every other 6 weeks or so. Still, it's
great fun and is something I have wanted to get into for a long time. Good
luck this year and, once again, thanks for the advice.

 

Unfortunately, the One Lap of America runs right over the Dragon this year, and I am not passing up the One Lap! Hopefully next year I can make it!

I'd love to come back out to Atlanta, with RSpeed and Hector/Joe, as well as Scott, there isn't a whole lot of need for pulleys in the area though. Drum up interest - I miss Georgia!

Randy

 

I have the small 19mm hsport bar and I have tried with 1.5* in the rear. The car just wouldn't rotate enough so I popped the rear out .5* Not too much difference but still noticable.

With the larger bars you could easily run the 1.5*

 

Pete,

I know we've discussed this, I don't wanta be adjusting constantly either.

But in case I didn't give you these numbers, I use -1.9, 0 toe-in/out front; -1.6, 1/16th toe-in rear all the time, no obvious wear problems, and pretty good on the auto-x. I may experiment this year with -2.1, 0 front and leave the rear as is. 15" wheels - both street and auto-x.

22mm alta bar, on first setting (it only has two, so the first is similar to midway between the first and second H-Sport).

The car is almost too touchy for street, but it's not bad. I'm guessing the currrent setting is about as radical as I can go for Atlanta street use.

It was actually a bit twitchy on the dyno today, until they got it stabiized...

 

Jim,

My memory was pretty good for what you told me you were running; it
jibed pretty well with what you wrote. I've taken in eveyone's suggestions
and I think I will go with -2.0, 0 toe-in in the front and -1.4, 1/16 toe-in
in the rear. I will then keep an eye on the tire wear, see how it feels at the
test'n'tune day and the AutoX the day after, and then decide if I want to
make any adjustments.

Once again, I want to thank you guys for your input. It is very helpful. The
concepts aren't difficult to grasp, but it is the practical working knowledge
and experience which I lack.

 

Thought I would throw a question in as I'm learning the car too.

Randy, a couple of sources suggest a 1/16" toe out in the rear. My initial reaction to that is, unstable! I've come to learn that rear toe can affect stability, and in particular, straight line driving more than front toe. And so, that recommendation feels a little too twitchy to me on anything but a very very tight autotX course. What do you think?