- My model of MX-5 is: 2.0 ND RF
- I’m based near: Hampshire
- I’m looking for technical help or recommendations on: ND ride height and wheel size for track days
I’m running stock 17" wheels with stock tyre size (205/45).
I’m running Meister R Clubrace GT1 suspension.
I did about 35 laps of the Nurburgring earlier this week and now have big holes in my offside front wheel arch liner from riding the carousels too fast! Before the nurburging, I could see just minor evidence of both front tyres making occasional contact with both liners, probably from riding curbs on track, but I never noticed when driving.
Is the obvious solution simply to increase my ride height slightly? Or how about 16" wheels? Or a bit of both?
Thanks 
Hi,
Do you use your car on the road? If so it will be important to make sure your rolling radius is the same otherwise your speedo might be out.
With a similar rolling radius you’ll probably end up with the same issues of rubbing.
Is your suspension adjustable for stiffness? If so, you could try stiffening the dampers?
Otherwise you may need to increase the rise height or remove the plastic wheel arch liners.
Cheers,
Guy
If you’ve increased the castor when doing the alignment (as many do, including me) to try and get some steering feel this will affect tyre/liner clearance.
I can’t remember what mine maxed out at (9 degrees?) but I’m running Tein flex z’s fairly low and soft, with OZ 7x17 and 215/45 assy 5, and very occasionally I get contact with the front of the liner when steering just off centre. I was going to heat gun it out of the way as it’s only a tiny area affected, which maybe a thought for yours.
Where has yours worn through and what height is are you running?
Mine is 335mm top of arch to centre of wheel, and in all honesty I’m surprised it doesn’t rub more. I have a feeling it would on the carousel rumble strips though!
I’m just outside Southampton.
reducing wheel diameter to 16" you increase the side aspect ratio (if you keeping the same width tyres) so you choose a tyre that wont have much difference to the previous tyre overall diameter.
Aftermarket suspension generally go for reduced height of the car but at Nürburgring the track is very bumpy so if you intend to use the car at Nürburgring and I dont know if you bottomed the suspension but if you haven’t I’d say then yea you need to increase the height of the car as far as your suspension allow.
Probably your ride height is too low,. A few MM higher or you’ll have to fit stiffer springs or ARB s.
Thanks for the comments and suggestions 
Here are a couple of photos:
I can see I’m just catching something under the liner, so removing or modifying the liner won’t be quite enough.
Front settings are as follows:
Springs: 10 kg/mm
Ride height: 315mm
Castor: 8°15’ / 8°08’ (thanks @Overdrive - hadn’t thought of this contributing!)
Total toe: 0°01’
Camber: -2°35’ / -2°34’
Wheels: Stock 17"
Tyres: 205/45 Yoko A052 (very slightly bigger than the stock bridgestones)
Anti roll bar: Stock (stock on rear too)
Damping is adjustable, but I don’t want to be adjusting it to solve this problem. I also don’t want to change the springs to solve this problem.
One downside of raising the ride height is I think I’ll reduce the amount of -ve camber that’s possible with the stock arms. I will change the arms if I think I need to.
The Meister-R Clubrace GT1s have separate valving for high and low speed. I suspect I might compress more when I ride the curbs and carousel compared to having the standard Meister-R dampers.
I don’t mind the speedo over-reading a bit with smaller wheels, if I go down that route. The slightly lower gearing will be beneficial on track.
@Overdrive, what is ‘assy 5’ ?
I’m near the A3, North of Portsmouth
Goodyear Eagle F1 assymetric 5. It’s sort of Goodyears version of Michelin PS4s, but has stiffer sidewalls so in theory should turn in better at the expense of a slightly harsher ride, or so I’m told.
If you’ve not had clearance issues before, and the only time it’s fouled badly is over repeated short bumps it could be that the rebound damping is too stiff, meaning that over quickly repeated short bumps there’s not enough time for the sring to return to it’s original length, effectively ‘pumping’ the suspension down.
Could you reduce the high (damper) speed rebound damping a tad?, and possibly increase the hs compression damping?
The camber you’re running could be adding to the problem as it looks like the outer side of the treaded part of the tyre is rubbing worse than the inner part, difficult to see from the photos if that’s relevant.
There seems to be lots of info on tracking the ND on the American sites, and iirc they prefer 15” wheels due to the choice of tyres available.
Running at the ring however is probably a different matter.
My 5 is/was my daily, so I haven’t been able to go too mad, and tbh usually use it for bimbling around the lanes rarely now. Bit of a waste really.
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Thanks @Overdrive; I’d not considered that they may be packing down, but that would make sense on the quick succession of bumps on the carousel. There is no separate compression / rebound adjustment, and no separate low / high speed adjustment.
It does seem quite common to run 16" wheels. SPS Motorsport recommends 16" wheels and I seem to recall reading somewhere that they themselves run 15". Other people I’ve been chatting to have recommended 16"
I used the ride height out of the box (I had to start somewhere!), but making sure it was level. This is about 315mm. There’s a post on a US forum saying that Meister R quote 12.5" (318mm) as the optimum height - I can’t find this in any of the documentation, but it’s probably not a coincidence that this is how they were supplied.
I’ve emailed Meister R to see what they say about ride height, and also to ask if the adjusters affect both low and high speed damping.
Not only that, but your car will probably record a higher mileage than it is actually doing so you may need to bear that in mind.
