Ohlins coilovers+alignment

[david45]

Finally pulled the trigger on some Ohlins coilovers as well as an Ecutek tune from Moto-East for my 2012 Club with prht. The Miata is my daily driver and height will be set at 13'' front and 13.25'' rear. I don't auto-cross or anything and I spend quite a bit of time on the highway (50% if not more).
So it looks like the technician will be shouting for 1.2 negative camber all around, max castor and slight toe-in of 1/32 per side front and back.
OEM wheels and tires with only 17k miles on the counter but I am planning on mounting some 215/45/R17 Michelin Super Sport tires on the same wheels for the next season in about 10 months or so.
What I am wondering is if a $100 alignment is going to be needed again when I make the switch to the 215/45/17 tires. They are about .3'' taller so I am expecting the answer to be yes, in which case I might consider making the switch right away.
What kind of change can be expected in terms of camber and toe with the taller tires? Is there anyway this could be compensated for a bit when setting the parameter with the 205/45/17 tires?

Cheers,

David

[Brian]

Tire size and alignment settings not really related.

You can go taller or shorter, wider or narrower, no need to change anything with alignment.

All the guys racing have one set of tires for street, another for racing and they don't align it again every time they swap tires. They will typically run more camber than you are going to run, but that's about trying to go fast on weekends and despite fact it may wear their street tires a bit much on insides.

[david45]

Thanks for the reply Brian.
One less thing to worry about

[david45]

Brian,

I was told on the miatanet forum that -1.2 camber was going to be difficult to get with the Ohlins coilovers and that -2.0 was more realistic. Is this really the case? Height will most likely be set at the suggested 13.25'' front and 13.50'' rear. I'm at about 50/50 highway driving.

Cheers,

David

[Brian]

The higher you go, the less camber you can get.

So indeed you might end up going back up to 13.5 heights all around if really set on just 1.2 negative camber.

That's the great thing about coilovers, you can set heights as you want....and later change as you feel the need.

[Chuck H]

Brian,

I was told on the miatanet forum that -1.2 camber was going to be difficult to get with the Ohlins coilovers and that -2.0 was more realistic. Is this really the case? Height will most likely be set at the suggested 13.25'' front and 13.50'' rear. I'm at about 50/50 highway driving.

Cheers,

David

Not sure why you have your heart set on 1.2 deg of negative camber all around. You can run quite a bit more than that with no adverse effects on tire wear, and the car will handle a lot better. At stock ride height, it's hard to get the rear camber as low as 1.2, and I don't think you're going to be able to get there at 13.5" ride height. I'd go for at least 1.5 in back, and either the same or even a bit more in front. You don't really need to worry about tire wear until you get well above 2 deg. Alignment techs always try to scare you about how camber is going to wear your tires out, but really, toe is the thing that eats them up quickly. The 1/32" toe-in that you're looking for is perfectly fine, but some bad alignments end up with something like 1/4" of toe, and that will wear the edges of the tires very quickly.

[david45]

Not sure why you have your heart set on 1.2 deg of negative camber all around. You can run quite a bit more than that with no adverse effects on tire wear, and the car will handle a lot better. At stock ride height, it's hard to get the rear camber as low as 1.2, and I don't think you're going to be able to get there at 13.5" ride height. I'd go for at least 1.5 in back, and either the same or even a bit more in front. You don't really need to worry about tire wear until you get well above 2 deg. Alignment techs always try to scare you about how camber is going to wear your tires out, but really, toe is the thing that eats them up quickly. The 1/32" toe-in that you're looking for is perfectly fine, but some bad alignments end up with something like 1/4" of toe, and that will wear the edges of the tires very quickly.

In this case I'll try to get to 1.5 negative camber all around and will know that it's not really the end of the world if I can't get there. I was indeed simply worried about tire wear...

[david45]

The higher you go, the less camber you can get.

So indeed you might end up going back up to 13.5 heights all around if really set on just 1.2 negative camber.

That's the great thing about coilovers, you can set heights as you want....and later change as you feel the need.

Thanks for the reply Brian