Too much Oversteer

Wheels, Suspension, Brakes & Tyres questions and answers

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LMW

Too much Oversteer

Postby LMW » Sat Sep 27, 2008 7:58 pm

Have had my 1994, 1.8l NA for a coule of month now and really enjoying the experience. It is fitted with 14x6 alloys with no name tyres with heaps of tread and I think a standard suspension setup. Car has a tendency to oversteer giving me a spin first time in the wet. At time I was not pushing it and also consider myself a reasonable driver. What tyre pressures do old hands recommend and if this does not resolve the problem what suspension mods are recommended. I am only interested in a comfortable good handling car for road use.

Thanks
Lindsay

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AJ
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Too much Oversteer

Postby AJ » Sat Sep 27, 2008 8:04 pm

chuck the tyres & get some good quality ones, that'll solve your problem :)

oh, & get a good wheel alignment when you do :wink:
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Too much Oversteer

Postby Jimi » Sat Sep 27, 2008 8:12 pm

As said above, a wheel alignment should solve all your problems. Just make sure there is more nagative camber at the rear wheels than at the front - Typically the front should be approx negative 1 degree and the rear should be negative 1.5 degrees - for "sporty" driving styles. These numbers were from another thread on here that I can't find at this second... At any rate, a reasonable wheel alignment should greatly help.

This should make the car fairly neutral when using equal tyre pressures.
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Hellmun
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Too much Oversteer

Postby Hellmun » Sat Sep 27, 2008 8:14 pm

Lots of things can cause oversteer..... You need to identify what you have first before you change things. Measure the width of the sway bars with some verniers. Does it have a LSD? What brand tyres? Are you sure you were smooth with the throttle and steering? If you can't identify the shocks I'm sure you could take a picture and show people here.

LMW

Too much Oversteer

Postby LMW » Sat Sep 27, 2008 8:30 pm

Wow you guys don't muck around. Thanks for the very prompt replies. I have thought of most of them just not sure how much extra I want to invest (and explain to wife). I have considered new tyres but if I go that route would you recommend going up to 15x6.5 and if so what type of tyres. And yes I was driving smoothly when it spun as I am an old fart and got that out of my system 30 years ago.

Lindsay

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Too much Oversteer

Postby Jimi » Sat Sep 27, 2008 8:53 pm

No worries!

As for upsizing your wheels and tyres - I have put 15" wheels on my NA, with 195 wide tyres and the lower tyre profile does make the ride a little harsher, but the slightly wider tyres do improve cornering. It's a bit of a trade off.

Also, you can get wheel and tyre packages from Bob Janes, with 15" wheels, for little more than the cost of a set of good tyres. Also, I can honestly say the "Bob Jane" Xenon tyres are quite good, both in the wet and in the dry - having taken a set on track days, and club runs - but not quite as sticky as some more expensive tyres.

Just don't get an alignment done by Bob Janes... go to a proper suspension specialist!
Hope this helps!
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Too much Oversteer

Postby lightyear » Sat Sep 27, 2008 9:29 pm

Just change to some decent new tyres. When i bought mine i was power sliding around any corner that i felt like giving it some on. The tyres where old, but had plenty of tread. Just gone hard.

Now i don't try doing slides anymore as it sticks really well with the 205/15's.
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Matty
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Too much Oversteer

Postby Matty » Sun Sep 28, 2008 12:06 am

lightyear wrote:Just change to some decent new tyres. When i bought mine i was power sliding around any corner that i felt like giving it some on. The tyres where old, but had plenty of tread. Just gone hard.

QFT.

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Too much Oversteer

Postby Adam_NAclubman » Sun Sep 28, 2008 1:22 am

I'd play with tyre pressures first, on 32psi my car is frigging great, but 34psi sees it getting sideways quite a lot when pressing on.

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Too much Oversteer

Postby Steampunk » Sun Sep 28, 2008 10:10 pm

As a side note, don't forget, there is a difference between "handling" and "grip".
MX-5's are a great handling car, but that doesn't mean that you can hook it into a 90degree corner at 80km/h and expect it to grip all the way.

My friend's Lancer GSR doesn't handle as well, but it grips like all hell.

Perhaps it's just a simple matter of lack of experience and asking/expecting too much of your car's capabilities.
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Too much Oversteer

Postby Jimi » Sun Sep 28, 2008 10:39 pm

Adam_NAclubman wrote:I'd play with tyre pressures first, on 32psi my car is frigging great, but 34psi sees it getting sideways quite a lot when pressing on.


As a side topic, it may be useful to have a database of "Favourite tyre pressures" for wheel and tyre combinations. I personally run mine (89NA stock suspension on 15" 195s) at around 39psi and find that gives the best feedback of tyre grip around corners, and I also get fairly even tyre wear - although it's bumpy and rattly over poor roads.
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Matty
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Too much Oversteer

Postby Matty » Sun Sep 28, 2008 11:18 pm

1red5 wrote:As a side note, don't forget, there is a difference between "handling" and "grip".
MX-5's are a great handling car, but that doesn't mean that you can hook it into a 90degree corner at 80km/h and expect it to grip all the way.

My friend's Lancer GSR doesn't handle as well, but it grips like all hell.

Perhaps it's just a simple matter of lack of experience and asking/expecting too much of your car's capabilities.

in my experience, it's almost certainly the tyres. Once they go hard, the car will wheelspin and oversteer at any opportunity

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Too much Oversteer

Postby Garry » Mon Sep 29, 2008 9:49 am

Another vote for tyres AND a GOOD wheel alignment. It also depends what your coming from too. If you have been driving a FWD car for a long time then jump into a car as well balanced as the MX5 it's pretty easy to get the tail out because you dont have the terminal understeer you've been used to.
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OVERDRAWN

Too much Oversteer

Postby OVERDRAWN » Mon Sep 29, 2008 5:11 pm

Hi I run 15 x7 with 205's on my NA8,I recently had the wheels painted so I used my old 14x6 mags for a while. I found it to be a much nicer car,smoother and more direct,with the 14's. I weighed both, the 14's 13.1 kilo's 15's 16.7 kilo's a big difference in unsprung weight. So IMO buy some good 14 inch tyres and spend your money elswere on your 5

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Too much Oversteer

Postby Adam_NAclubman » Mon Sep 29, 2008 8:39 pm

I wouldnt even bother with good tyres, rubbish tyres have less grip but are usually more progressive as the grip runs out.


The others are right about the difference between handling and grip though, theres a very big difference


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