New to MX5 wanting advice.

[Budmeister]

At age 41, having just purchased my first sports car , a white 98 MX5 Nb 6 spd RS with 145km on the clock, I love it but have noticed its a bit drifty and light on bumpy windy roads. Is this normal for a sports car or could something be wrong ?. Handling on smooth roads is fine, shocks are fine, might get the alignment checked.
Any advice appreciated.

[poison]

What size wheels/tyres do you have? And are they directional? I have the same car with directional 215/40/17 (that or 225 I can’t recall). Anyway if you have wider, low profile tyres, especially directional they seem to track a lot more and be really hard work on uneven road surfaces. My previous MX had directional 205/60/16 tyres that were much nicer to drive on uneven roads. I am also considering a new alignment to improve handling. There are other discussions on this form regarding the best alignment settings.

Jif what do you think? Would your recommended settings make the steering heavy or lighter? I would guess heavy.

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[Growler]

I would check tyre pressures as well.
They could be over inflated (Or under inflated!).
I like a stiffer sidewall so I usually put in around 32psi. Anywhere between 30psi and 32psi should be fine.

[Budmeister]

Thanks for that Growler. Am getting some new Supercat tyres fitted by Tonys tommorrow (only $100 each) and alignment, but will check the pressures after its done.

[poison]

Well done on buying a 5…. It’s a good fun choice.

What size wheels/tyres do you have? And are they directional? I have the same car with directional 215/40/17 (that or 225 I can’t recall). With wider, low profile tyres, especially directional they seem to track a lot more and be really hard work on uneven road surfaces. My previous MX had directional 205/60/16 tyres that were much nicer to drive on uneven roads, it almost feels like I don’t have power steering. I am also considering a new alignment to improve handling. There are other discussions on this form regarding the best alignment settings.

Jif what do you think? Would your recommended settings make the steering heavy or lighter? I would guess heavy.

Supercat tyres??? Never heard of them, I wouldn’t rush into a set of cheap tyres, do some on-line research. After all it’s the only thing holding you onto the road on those windy roads… you’ve invested in a sports car which is great, and you should buy some tyres suited to the task. Again on this forum you will find lots of tyre discussions. And the result is two main contenders, Toyo and Bridgestone’s. I’m hoping to get some Toyo’s, I have the new Bridgestone’s on my company car, and they don’t seem any batter than the factory set that came with the car.

[jif]

Don't know if you've seen the alignment specs on miata.net or
miataturbo.net , but pay careful attention to the (rear) toe settings
if you're finding it too jumpy/drifty... you'll probably want some
toe-in unless you're the super hairy-chested, big-balled type!

If the car's been lowered that could be another factor, though since
it's an RS it could also be really stiff anti-roll bars Either one
could make it let go earlier.

Or it could be heavy wheels+tires causing it... if I go for a bit of a
fang with the shocks on soft it can get a bit floaty on bumpy corners
at just 80km/h+.

More negative camber (top of tyres leaning inwards) makes things
lighter... and less straight line grip, more in the twisties ... only
good if you really like to spank it in the corners.

more castor makes the steering heavier and more self-centering/stable.

Buy Yokohamas (C, A or S drives) ... they're awesome! Life's too
short for bad tyres

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[Ian]

Ditto 'cheap tyres' don't belong on an MX5!
Even the best tyres don't cost a fortune (esp if your RS is on factory size 195/50 x 15).....AND they last well, even with spirited driving.

[Stevo]

The "Supercat is the budget tyre marketed by Firestone for your shopping basket or commuter. You may find that the handling will be worse with those fitted. The MX5 is a superb handling car and should have good rubber fitted, allow no less than $140 per corner. Cheers Stevo

[marinerbluemx5]

Assuming your tires and pressures are fine, and that there's no mechanical damage to shocks/control arms/etc. (unlikely there is) then you can definitely sort out your handling with an alignment. It's quite amazing how much an alignment can alter a car's handling... can take it from understeering to neutral to oversteering (seems like yours might have this last one if it's feeling 'drifty'), all based on driver preferences.

But beware of regular alignment shops - the manufacturer's specs have huge tolerances, and your car can be horribly understeery or oversteery and still be within specs... so that the guy at the shop can tell you "it's aligned", even if it handles like a pig as a result.

What you want is to track down someone who will sit down with you before the alignment and talk about what the car currently feels like, what your goals are (for example, get it less drifty in your case), and how that can be achieved. Then there's details like ballasting the driver's side during the alignment - a typical shop will look at you like you're crazy if you ask them to put in your equivalent weight on the driver's seat, but think about it... the driver's half of the car weighs about 500 kg without driver, and, in my case, I add 80 kg when I sit in it, that's over 15% in added weight - it's going to affect the alignment. Finally, if they know MX5's, so much the better... I've had mechanics at Frank Allen Tyres and Beaurepaires Tyres try to convince me that you can't adjust front caster on the MX5.

And I completely agree with the others' tyre comments - choosing a poor one can really dull the MX5's handling and sportiness. Don't get me wrong, an MX5 on poor tyres is still more fun than most things out there, and you don't need to get super-expensive tires to have fun (mine were about $150 each).

[marinerbluemx5]

Oh, I forgot to say... congrats on the purchase, and welcome to the forum! You'll love the car, and the enthusiast community around it is great.

[Growler]

Then there's details like ballasting the driver's side during the alignment - a typical shop will look at you like you're crazy if you ask them to put in your equivalent weight on the driver's seat, but think about it... the driver's half of the car weighs about 500 kg without driver, and, in my case, I add 80 kg when I sit in it, that's over 15% in added weight - it's going to affect the alignment.

This is correct if you are after the altermate setup and you only have room for the driver.
This will all change once you have a passenger in the car.
I would talk to a few people here to see what they run and you should start to get an idea of what camber, caster toe etc people run.
In the first instance I would get the alignment checked just to make sure none of the settings are way out.
There is nothing wrong with the factory settings. You can start to change them once you have driven the car for a while, understand what the car does and how it feels before you make alterations.

[marinerbluemx5]

Then there's details like ballasting the driver's side during the alignment - a typical shop will look at you like you're crazy if you ask them to put in your equivalent weight on the driver's seat, but think about it... the driver's half of the car weighs about 500 kg without driver, and, in my case, I add 80 kg when I sit in it, that's over 15% in added weight - it's going to affect the alignment.

This is correct if you are after the altermate setup and you only have room for the driver.
This will all change once you have a passenger in the car.
I would talk to a few people here to see what they run and you should start to get an idea of what camber, caster toe etc people run.
In the first instance I would get the alignment checked just to make sure none of the settings are way out.
There is nothing wrong with the factory settings. You can start to change them once you have driven the car for a while, understand what the car does and how it feels before you make alterations.

Actually yeah, my mistake, I just kind of assumed the original poster had the same goals that I do (a fast track-oriented single-occupant setup). But as you point out, it depends on what he wants to do - and if it's like most MX5's out there, then probably it'll be driven with the significant other in the passenger seat, during weekends, on normal roads at normal speeds. Nothing wrong with that, just different goals, which benefit from different alignments.

Also, I completely agree with the need to take it gradually and get used to the car, then change only one thing at a time and clearly see the effect that the upgrade has.

I will say this though: the stock alignment settings might be passable, but I felt a huge difference when I went from the standard factory-spec alignment to more aggressively cambered alignment (along with some caster and toe tweaks). It's almost like an entirely different car now, feels incredibly planted in fast sweepers, whereas before it felt kind of vague and nervous.

Although I should qualify all this by saying it's important to talk with the mechanic about your goals and what you'll put up with - improved handling from a more aggressive alignment may come at the cost of increased tire wear, more dartiness on highways and heavier steering, and everyone has different preferences/needs/patience when it comes to those kinds of things.

[Budmeister]

Thanks for all your advice, its much appreciated.

Whats I find very comforting is I can go on here with a problem and get a whole lot of enthusiasts unbiased advice and take it from there, what other car can you do that with !!!!.

Im more just a weekend casual driver, rather than a track day enthusiast so will get the alignment done and see if that helps. The whole car only set me back $8k which I consider a bargain, looks like a little viper.

Thanks again for all your help guys.

[Ian]

Bud....here are some suggested 'street' alignment settings which are know to work well.........
Front: Caster +5.0 degrees
Camber -0.7 degrees
Toe 1/16" total

Rear: Camber -1.2 degrees
Toe 1/16" total

These are fairly conservative settings, but are a good starting point.

Cheers, Ian

[Growler]

Actually yeah, my mistake, I just kind of assumed the original poster had the same goals that I do (a fast track-oriented single-occupant setup). But as you point out, it depends on what he wants to do - and if it's like most MX5's out there, then probably it'll be driven with the significant other in the passenger seat, during weekends, on normal roads at normal speeds. Nothing wrong with that, just different goals, which benefit from different alignments.

Also, I completely agree with the need to take it gradually and get used to the car, then change only one thing at a time and clearly see the effect that the upgrade has.

I will say this though: the stock alignment settings might be passable, but I felt a huge difference when I went from the standard factory-spec alignment to more aggressively cambered alignment (along with some caster and toe tweaks). It's almost like an entirely different car now, feels incredibly planted in fast sweepers, whereas before it felt kind of vague and nervous.

Although I should qualify all this by saying it's important to talk with the mechanic about your goals and what you'll put up with - improved handling from a more aggressive alignment may come at the cost of increased tire wear, more dartiness on highways and heavier steering, and everyone has different preferences/needs/patience when it comes to those kinds of things.

No mistake MarinerBlue. You want a race setup where someone else wants a road setup. Unfortunately you can't have both (I have tried! Mind you it was much eaiser than the race car!)

Just some final advice. Once you have the alignment done get a printout. That way if you are happy with the setup you have all of the settings that the car was set to on paper.

[Budmeister]

Update. Had the alignment done and 4 x Firestone Supercat budget tyres. Although quite sensitive on the steering, handles like a dream now and doesn't track off course or drift. Might have been having different tyres front and rear that was causing it as the alignment wasn't too far out.

[sprsta]

doesnt take much for the alignment to be out
my first few wheel alignments were within spec but it never felt right i used my own specs and they got them perfectly accurate it was amazing the difference