I have had my MCS for a week and did the following upgrades. I put each on and drove approx 30 miles testing each. First 18" excel wheels and 215/35 TOYO proxes 4... note let the twitchyness begin . Here I noticed that when the car hits a slight dip or bump around a curve it likes to skip sideways and when I break HARD VERY HARD it wants to drift/pull to one side then then the other like a sway.Also I took it out to a huge open space and opened her up when I got to about 100+ I no longer felt like I had control the car would follow the pavement defects and small bumps would cause the car to feel like I was out of control. So then I am thinking it will get better when I put on the KW coilovers and NOPE tried all sorts of different rebound settings same thing. Took it back to get her aligned no change. I had already bought a set of eibach spring before the coilovers came...So in my spare time:smile: I put these on. The handling was better (from my uneducated point of view) but still twitchy. So I am thinking it is the TOYOS or maybe this is a function of having very low profile tires. So I put the KWs back on and am playing with it. I will say that I can't get these tire to break lose sideways for nothing, but maybe that same grip is also causing the twitchyness . When I say twitchy I mean the car just feels like it wants to SKIP around...almost feels to light. Now maybe I just need to get used to the car. Any help is appreciated.

 

sounds like too much 'toe' out.

 

Perhaps as Onasled wrote, or too much toe out in the rear. Rear toe can have a very big effect on stability, I beleive more so than the front. But, more than likely your wandering problems are the result of your ultra low profile tires tram-tracking. Ultra low profile tires will grab at just about any imperfection in the road. Since the Mini's suspension wasn't really designed to work with 35 series tires, I would look here first. A fix that essentially ignores all else is to add a bit of toe in the front and rear. The forces acting on the tires in this configuration cancel each other out creating a more stabile high speed atmosphere. Of course, the car will likely understeer into every turn. But then you could add a bigger rear bar and well you get the picture; part A is connected to part B which is connected to part C and so on.

Personally, 40 series tires are low enough. That written, JCW wheels are 18", so go figure. Try a set of 40 or 45 series tires back to back against your 35's. That is much easier than changing springs and dampers.

Let us know, and good luck

 

I would install your factory wheels/tires and see if that helps.

 

Yeah, that is the first thing I thought of

 

Thanks I will try the wheel swap tomorrow. I do hope that works.

 

How much offset do those wheels have? If the wheels are set much wider than stock, and toe out was already at the outside edge of the spec, the wheels would simply make it worse. It could also affect camber. You'd need an alignment of stock wheels vs the new ones to get an idea of any changes in this regard.

The 35 series tires would also aggravate the problem as there's much less give in the carcass than a 45 series, or 55 if running 16s. I run 215x40x17 on K1 wheels and as the tires have worn, the car wanders more and more easily than with fresh rubber. THat will happen since the softer tread surface has been worn off and the wheel/tire package is more rigid.

My guess is a 35 series tire is basically worthless as a street tire. Might be ok on the track where the pavement is better... Or you may need a lot more toe in front and rear to help the problem.

 

Thanks for the input. They are 42 offset. I guess after they wear down I could switch to 40 series. This is a whole new learning experience for me. I am hoping it does not end up being a costly learning experience.

 

My factory 15" holies with the conties can do sweeping curves at 125 MPH and the car is solid,in control,and still has room to go more.

 

No man, it's all good. Learning is good. You'll get it worked out.

 

Well try the factory wheels/tires first and see. It could just be
your alignment.

I would run 215/35/18's if I was running 18 wheels on this car. not sure
of Toyo's but probably some dressup tire similar to that. 215/35's are
fine for street use as long as you don't hit any major bumps/pot holes.

 

Sounds like the tires are just following the grooves in the road. This isn't uncommon with low profile tires.

Your story is rambling, but it appears that it started after putting on the new wheels/tires. That's where the troubleshooting should have ended. Continueing to change other aspects of the car isn't going to change the properties of the wheels/tires.

 

Signature images - wasting bandwidth and cluttering messageboards worldwide.

Cant we just make more. I just could not resist the temptation to have an image. But now I am wasting B/W talking about wasting bandwidth.

Anyway to the point I decided to lower the pressure (about 5 psi) and am going to try and run it out on an old but well paved city dump road at lunch. I did not check the pressure (as I should of) they had 52 psi and I lowered them to around 46+/- psi. Then I will try the wheel swap. I just hate to not used the wheels and have wasted 1100 so I am trying everything to keep them on.

And I took my image off just for you

 

Well! 52psi will certainly cause wandering problems. I had a set of tires mounted several years ago, Yokahomas if I remember. I went for a 60-70 mph ride on the highway afterward. The car was unstable at these speeds, lost all of its tracking. I decided to first check the tire pressure and sure enough, it was in the low 50's. By the way, 45psi cold - front and rear - is high enough for the street. Perhaps a bit more for autoXing.

Some folks advocate setting front psi higher than the rear. If suspension balance is off, adjust the suspension, not the tire psi. Keep the psi for front and rear within optimum operating range.

Ciao

 

52psi??!!


Lower them to 38psi in the winter time, 36 in the summer.

 

My god, 52psi?!?!? What kind of tires are these? My BFG's MAX psi is 51.. I run them at about 36psi at all corners....Why would you put so much in? That's bordering on unsafe...Also, what is your sway bar set at? If it is at full stiff, set it back a notch or so and see what happens.

 

You're doing all this on a new engine and new brakes?!

 

The tires were assumingly set at the alignment place. I have backed away the sway to the softest setting. And yes all on an engine that now has 225 miles (dang she is already getting old) . I did not think that the suspension and tire mods would have any effect on anything other than the suspension. I am waiting another 1000 miles to do the pulley and exhaust. I don't go over the 4000 rpm except once or twice...OK maybe 4 or 5 times but thats all I'm saying since I know that the MINI warantee police are watching .

 

52psi You're probably running on a few dimes worth of contact patch No wonder you're skiddn around like it's on ice...

 

Yeah, avoid that shop if they're setting a 2700ish lb. car to 52 psi. Sounds like they don't know tires, or their pressure gauge is screwed up who knows?

 

You obviously have the "modding fever" and we all applaud that. However, perhaps you should consider getting to know your car a little before changing so many things. It will allow you to better evaluate the changes and maybe, you will find out you don't need to change some things.

Also, if the alinement shop set your tire pressures to 52 psi and let you drive out of there, you might want to look for another shop!

Congrats on you purchase and enthusiasm.

Dave
Sunny San Diego (Finally!)
2003 DS/B MCS, 15%, RO-JA's and AVS's about to go on!

 

That is crazy pressures. I don't run that high for AutoX. For the street I generally run 37F and 33R.

 

Ran it at 38 all around. It is great . I can't believe that I did not check that first .

 

well, at least you got what you want now. I didn't think the 215/35/18's at +42mm offset would cause problem. Ive seen many people run that tire size on the streets too.

 

SRIGHT:

WOW -- All those OMG's and 's and 's and e-dope slaps, and you're still ing! I am very impressed! :smile: