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Alignment

PostPosted: Thu May 03, 2018 9:03 am
by Apexcone
Hi Everybody its been a while since I was last here. I have a 2015 NC Club. It has Koni dampers, Progress Springs, sway bars and uprated bump stops.

Looking for a custom alignment car will be used for Autocross, track days and city driving. Be grateful of any input.

Terry

Re: Alignment

PostPosted: Thu May 03, 2018 10:28 am
by Brian
Alignment depends much on what you do with the car. Assuming no autocross or track use, for pure street driving our usual suggestion looks like this for those springs and shocks:

Front Camber -1.2
Toe IN 1/32nd per side (some shops call this 1/16th 'total' toe in).
Caster 6

Rear Camber -1.2
Toe IN 1/32nd per side

Racers will take much more camber (and usually full coilovers instead of just these very mild street springs). Autocross customers will toe OUT the front, track users usually toe ZERO front and rear. Downsides of toe out at the front is tramline behavior on the freeway, car might feel a little 'darty'. I am accustomed to that slightly nervous 'wants to turn' feel, but it bothers some. If you care more about the autocross and track days than tire longevity then I would max the camber, and note that beyond 1.5 we try to account for fact that rear multi-link is much more aggressive for camber curve. With that in mind, we would seek:

Front Camber -2.2
Toe ...OUT....1/32nd per side (some shops call this 1/16th 'total' toe OUT).
Caster 6

Rear Camber -1.8
Toe IN 1/32nd per side

You may not get this much negative camber....but I would take it if I can get it for those autocross and track days. Tire wear on long boring freeway drives may suffer some inside shoulder wear, all depends on your mix of fun vs boring driving.

Re: Alignment

PostPosted: Thu May 03, 2018 6:03 pm
by Apexcone
Thanks I really appreciate the input.

Re: Alignment

PostPosted: Thu May 31, 2018 4:55 pm
by BradW603
Hi, I also have an alignment question.

I have an NC that is being built as a race only stripped, caged, road course car. RX8 progress sways and Feal road race coilovers going on next week before my first race.

Car was originally planned to run on Hoosiers. Our series just got sponsored by Continental and we are now running on street tw340 Extreme Contact Sports.

What would be a good starting point alignment for that setup?

Ride height?

Thanks!

Re: Alignment

PostPosted: Fri Jun 01, 2018 3:03 am
by Brian
Hmm, hard tire compound but extremely soft sidewall. You need camber, as much as you can get. Can you legally use offset bushings? If so, do it and take all the camber you can get. You didn't mention tire size which has some impact on height but roughly 4.5 inches from ground to pinch welds. These are numbers well beyond what you can get unless you have the offset bushings so finding out if those are legal for your class is key to what comes next.

Front Camber -3.4
Toe zero
Caster 6.5

Rear Camber -2.8
Toe zero to very slight toe in.

Brian

Re: Alignment

PostPosted: Fri Jun 01, 2018 3:05 am
by Brian
Hmm, hard tire compound but extremely soft sidewall. You need camber, as much as you can get. Can you legally use offset bushings? If so, do it and take all the camber you can get. You didn't mention tire size which has some impact on height but roughly 4.5 inches from ground to pinch welds. These are numbers well beyond what you can get unless you have the offset bushings so finding out if those are legal for your class is key to what comes next.

Front Camber -3.4
Toe zero
Caster 6.5

Rear Camber -2.8
Toe zero to very slight toe in, typically 1/32 toe in per side because NC will toe out under load.

Brian

Re: Alignment

PostPosted: Tue Jun 19, 2018 5:14 am
by Joey
Hello Everyone,

I have a new to me 04 MSM. It's going to be an Autox and weekend toy mainly for my wife. Not sure on the suspension yet. It came with a set of Afco double adjustables that require a complete rebuild due to some water getting in them. They need shafts and everything. Looks about $1450ish for the rebuild or just get a new set of Ohlins Road and Track. Still trying to decide. Either would be way overkill for her though. Doesn't really affect alignment settings but, not sure on the wheel\tire combo yet except that it will be a 200 treadwear autox street tire.

I see the specs in this thread are for an NC. What would you recommend for the NB? Shock, wheel\tire, and alignment spec recommendations?

Thanks,
Joey

Re: Alignment

PostPosted: Tue Jun 19, 2018 7:58 am
by Brian
NA/NB is very different, not a multi-link rear like NC/ND. With NA/NB we tend to toe in the rear, toe out the front for autocross, despite some tramline results, and we take more rear negative camber. This is typical.

Front camber -2 or better depending on how low you are and how much you can get at that height.
Front toe zero to POSITIVE 1/8 (within factory range) Caster--As much positive as you can get with the above settings.

Rear camber -3
Rear toe zero to NEGATIVE 1/8 (within factory range)

Re: Alignment

PostPosted: Tue Jun 19, 2018 9:36 am
by Joey
Thanks for the reply :D
Joey

Re: Alignment

PostPosted: Wed Jun 20, 2018 9:13 am
by JimH771
Hello,

I also have a similar alignment question to add on. I have a 2011 PRHT with Progress springs and Koni shocks. This is mainly a street car. I installed them and then drove my 600ish miles and they settled nicely and evenly. I took them to a known performance alignment shop here in NC and asked for your recommended street specs (1.2 neg camber all around). After getting under there he said he got 1.2 neg in the front fine but both rears maxed out at 1.9 neg (with 200lb me in the car) and that was the best he could get. Is that normal? I went with zero toe in the back to help on tire wear as I just got BFG Gforce 215's and don't want to chew them up. I looked and there are some adjustable camber arms I could get.

I've just not heard of people needing camber arms with a mild setup and wondered.

Thanks,

Jim

Re: Alignment

PostPosted: Wed Jun 20, 2018 10:05 am
by Brian
Hmm, so he is saying 1.9 was LOWEST amount of camber he could get at the rear? That does surprise me a little, but not a lot. That's not an extreme amount of camber for car this light, if rear toe is set zero or very slightly negative that should be okay on tire wear, particularly if you rotate your tires every 6 months.

Re: Alignment

PostPosted: Wed Jun 20, 2018 5:44 pm
by JimH771
Yes, 1.9 was the lowest. Well, thanks Brian, makes me feel better that it is semi normal. With me in the car and a full tank of gas has an effect too I geuss. He knows Miata's from what I hear (and he thought your recommended street specs were great) so I'm fairly comfortable that is how things were.

Thanks for the help, I appreciate all you do for the Miata community!

Jim