NC oversteering / slipping problem

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NitroDann
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Re: NC oversteering / slipping problem

Postby NitroDann » Wed Aug 29, 2018 12:19 pm

Stock NC springrate is 110lb front 90lb rear I believe.

Thats a 22% stiffer front.

If he has 12/9 thats actually more understeer biased, and 9/4 is extremely understeer biased in comparison.

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JBT
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Re: NC oversteering / slipping problem

Postby JBT » Wed Aug 29, 2018 12:45 pm

A Club friend who, like me, enjoys a "spirited" drive has MCAs fitted to his NC with stock sway bars. His car handles perfectly. MCA set-ups do not work with aftermarket sways.

I agree that tyre pressure could be an issue. I'd also get a second opinion on the wheel alignment. I find 30-32 psi cold work just right for street.

My NC has Tein Flex Z and Whiteline adjustable sways. The sways were on before the Teins. Fulcrum (Tein AU agents) recommended sticking with the aftermarket sways but the Tein springs are much softer than MCA. Mine is like a go cart.

I have recently had MCA street essentials fitted to my BMW E82 and the difference from stock is astounding. The car handles almost as well as the MX-5 now instead of plow, dive, undertseer.

I doubt the problem is MCA. Maybe a track day would help you sort the problem.
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Re: NC oversteering / slipping problem

Postby RS2000 » Wed Aug 29, 2018 3:44 pm

Rear toe might be way off. Was the alignment done by someone who knows what they're doing?

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Re: NC oversteering / slipping problem

Postby mitch027 » Wed Aug 29, 2018 4:38 pm

get an alignment done with a print out

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Re: NC oversteering / slipping problem

Postby Regie » Wed Aug 29, 2018 9:09 pm

I see you are running Kumho KU31's

they have been out of production for approx 4 years.

Get yourself some new tyres. awesome tyres around in the 215/225 profile which is what you'll want
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Re: NC oversteering / slipping problem

Postby bliu6757 » Wed Aug 29, 2018 9:13 pm

Regie wrote:I see you are running Kumho KU31's

they have been out of production for approx 4 years.

Get yourself some new tyres. awesome tyres around in the 215/225 profile which is what you'll want


Got myself some pilot sport 4 21545r17. Next is alignment. Any good and affordable places in the northwest suburbs?


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Re: NC oversteering / slipping problem

Postby Regie » Wed Aug 29, 2018 9:16 pm

northwest suburbs of where?

if Syd could always hit up mania, im sure they do alignments there.

so still oversteers with the new tyres?
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Re: NC oversteering / slipping problem

Postby JBT » Wed Aug 29, 2018 9:18 pm

Just settle for good or excellent and knowledgeable. Which city?
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Re: NC oversteering / slipping problem

Postby Custardtart » Wed Aug 29, 2018 9:21 pm

The best way to approach this is to eliminate known issues first.
So, change the tyres. 4 yr old worn tyres can be utterly useless. You didn’t need semi slicks but half decent rubber like Bridgestone RE003’s or Hankook rS4’s will provide all the grip you would want on the road.

Next up, get an alignment done from an MX5 specialist.
Ask them to check your sway bars are all ok, not loose etc.

Assuming that’s all ok, don’t touch the sway bars. The OEM set up is fine for all but serious track use. Stiffer front bars can provide the driver with a flatter, more precise turn in on a road car but in reality will result in more understeer.

If your still struggling, ask MCA to dyno the shocks, it’s rare but sometimes seriously mismatched shocks can lead to pretty bad handling issues.

Failing that, it’s probably your driving approach or the car has a bent chassis.
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Re: NC oversteering / slipping problem

Postby bliu6757 » Wed Aug 29, 2018 10:12 pm

Regie wrote:northwest suburbs of where?

if Syd could always hit up mania, im sure they do alignments there.

so still oversteers with the new tyres?


Ye probs have them have a look.

Getting the tyres fitted this Saturday. Will let you know.


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Re: NC oversteering / slipping problem

Postby bliu6757 » Wed Aug 29, 2018 10:22 pm

Custardtart wrote:The best way to approach this is to eliminate known issues first.
So, change the tyres. 4 yr old worn tyres can be utterly useless. You didn’t need semi slicks but half decent rubber like Bridgestone RE003’s or Hankook rS4’s will provide all the grip you would want on the road.

Next up, get an alignment done from an MX5 specialist.
Ask them to check your sway bars are all ok, not loose etc.

Assuming that’s all ok, don’t touch the sway bars. The OEM set up is fine for all but serious track use. Stiffer front bars can provide the driver with a flatter, more precise turn in on a road car but in reality will result in more understeer.

If your still struggling, ask MCA to dyno the shocks, it’s rare but sometimes seriously mismatched shocks can lead to pretty bad handling issues.

Failing that, it’s probably your driving approach or the car has a bent chassis.


Thanks for the detailed response. I’m getting the tyres fitted this weekend so will have a look. I plan to have an alignment done ASAP after fitting the tyres. The ps4 came cheaper than the other two so I opted for them.

Hmm.. I’m not sure whether this changes anything.. however, when I first got my mca blues, the right rear coils kept knocking. Called mca and was told it was ok to drive. But when my mate lifted it up with a hoist, it literally broke apart by itself I.e all the liquid the coils just fell apart. Josh was kind enough to send me a replacement straight away. However with all the trouble I went through, I did plan to do a review, just never had time. Since, there has been so many good reviews, I didn’t want to blame the oversteer on mca. However, now you have mentioned it.. I am wondering if that would be the case.

I’m thinking I really need a good mx5 specialist to give it a look. Is there any reputable ones in Sydney?

I know mca recommended me to try vsport. What’s everyone else’s experience?

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Re: NC oversteering / slipping problem

Postby JBT » Thu Aug 30, 2018 8:15 am

:shock: Something is seriously wrong there for the shock/damper to come apart. I can't say I've ever seen anything like that before.
Very bad look for MCA and they should thoroughly check this whole set-up on-site through an agent.
Were both rear shocks replaced?
Are both rear shocks set to the same stiffness?
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Re: NC oversteering / slipping problem

Postby Regie » Thu Aug 30, 2018 10:06 am

wow

then again thats not the first time ive herd/seen MCA quality control issues.

Forget about posting anything more until you have your new tyres installed. that will fix everything

MX5 mania as I mentioned above is a MX5 specialist located in Dural
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Re: NC oversteering / slipping problem

Postby bliu6757 » Thu Aug 30, 2018 10:07 am

JBT wrote::shock: Something is seriously wrong there for the shock/damper to come apart. I can't say I've ever seen anything like that before.
Very bad look for MCA and they should thoroughly check this whole set-up on-site through an agent.
Were both rear shocks replaced?
Are both rear shocks set to the same stiffness?


I know. I never chased them about it after fitting the replacement. Maybe I should have.

Only the rear right one was replaced. The stiffness is set at the same setting.


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Re: NC oversteering / slipping problem

Postby Custardtart » Thu Aug 30, 2018 10:46 am

I’m in brisbane so don’t know any of the specialists in Sydney but a quick google showed MX5 Mania in Dural.
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