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flier129
03-07-2013, 10:42 PM
Hello all! I've forgotten about this forum so I shall contribute to it by proving my alignment setup and results over the next two weekends. I've got a local auto-x event this weekend and next weekend I'm heading to Dixie for a Solo II National "Match" Tour. My co-driver and I are going to make it a 3rd time win for a miata in STR :mrgreen:

Anyways, my current setup:
94 R 213k miles(yup)
XIDA CS 700/400
RB "race" fsb, RB end-links, no-rear(might run a rear on concrete, like at Blythville)
15x9 6uls, 225/45/15 RS3s

Current alignment, 3/7/13:
camber - -2.0f/-2.0r
caster - +5.8 both sides iirc
toe - 0f/0r

I've got 1" of travel before the bump-stops in the front and 1 1/8" in the rear. Which, from what I've read, is pretty typical of the XIDAs. Turns out to 4.25"F/4.50"R pinch-welds. The car was also corner-balanced and it seems to of made a huge difference, although I haven't been able to slide the car around any turns. The XIDAs operate very well at low ride-heights and I actually had the car a 1/4" lower f/r and it never gave me any fuss. It looks pretty weird on paper to have less than 1" of travel, but running without a rear-bar looks really sketchy when valuing FRC and I can't name many nationally prepped auto-x miatas that run a rear-bar regularly. Nevertheless, I'm happy with my current ride heights, it rides a lot better around town and it is my DD afterall :)

Taking a pyrometer to my tires this weekend while at the gap and at the autox event. I'll also post up our results of each event :).

Here's a recent pic of my car to break-up this book I've accidently wrote:
http://i48.photobucket.com/albums/f227/Flier129/metro1ccr2_zps2712e877.jpg


I have been running A LOT more camber and the current camber numbers isn't what I wanted, but I'm going to try it out.

My old setup(as per-949's alignment):
camber- -2.8f/-2.5r
caster- +5.5
toe- 0
4"f/4.25" pinch-welds(I forget the bump-travel it had, not much)

This setup seemed to have A LOT of grip, some under-steer on turn-in, and under-steer in slow 180 elements. After speaking with JohnWag @ AST-USA I'll be dialing out from front rebound if I find the car under-steering on the slow speed stuff, something I never even tried yet. I usually ran 12f/10r out of the 12 settings the ASTs have. We never had any issues with bumps or pavement transitions, even when other drivers complained :lol: In hindsight, I could of netted some mechanical grip on the front-end by running a little softer.

I can't rule-out my old-ass ball-joints and bushings in the data I'll acquire :(. That's something I'm hopefully addressing soon......after the engine :lol:

Keep in mind, any of my records and adjustments might change if I decide to switch to the BFG Rival. Hopefully watching the STS cars at Dixie will show me enough data of how they act on a NA miata to decide if I want to run them.

flier129
03-09-2013, 11:22 AM
I've decided to change my front alignment to - 2.4.

flier129
03-10-2013, 07:53 PM
Well, I wasn't able to get the front camber I wanted. I ended up with this:

camber: -2.1F left/ -1.8F right, -1.9 rear both sides.
toe: basically zero
caster: +4.4 left/ +5.2 right

Did the local event today, both my co-driver and I got pissed pretty quick lol. The car pushed a lot harder than it had before and the grip fell off pretty quick while under heavy loads. Took two decent readings with the pyrometer right as my co-driver came off the course. It was the 3rd and 4th run for the car that day. I didn't get as much data as I normally would, well I saw the results and just kind gave up LOL.

Ambient: 68* and partly cloudy

Front:
I - ~105
C- ~125
O- ~135

Rear:
I- ~110
C- ~130
O- ~135


The tires didn't get up to their happy temps of 140-170, especially these rs3s that love heat. As my results show..... I don't have enough camn damber damnit!!!!! 949's pyrometer write-up states that having the inside significantly cooler is a typical sign of not enough negative camber(can't copy it because of copy-rights, go read it on 949racing's site!)

So I'm lowering my car back down about a 1/4" to gain some more static negative camber, getting it aligned to MY SPECS and heading to Dixie next weekend.

flier129
03-10-2013, 08:03 PM
Here's my fastest run from today:

http://youtu.be/wDTS6LNhLWM

flier129
03-26-2013, 07:57 PM
Sorry for the long delay! Although, I doubt anyone cares because no one has responded :(

The Dixie Match Tour was a BLAST, even though I coned ALL of my runs, lol. Here's my fastest run, which would of put me into 5th if I would of kept it clean:
http://youtu.be/YZ7lhx7YY4QZ

Ok, so the Wednesday before the tour I lowered my car 3/16ths evenly in hopes of keeping the car relatively balanced from the corner-balance I got. I'm sure the cross-weight was within 50lbs of each other and that's good enough for me.

The next morning I went off to get the car aligned...... again. This time got with the guys at Finger Mazda in Greenville, SC. They were the best dealership I've ever dealt with, got the cars to my specs without fus, and even had me look at the specs before they finished it off. Most of all, they only charged me a flat-rate of $69!!!

I went back to my old specs:
camber: -2.7LF/-2.8RF , -2.4LR/-2.4RR
caster: +3.8L/+5.2R(it was off, only way to correct it was to take out front camber :( )
toe: 0 all

My co-driver and I weren't able to get any practice runs on Friday, so we didn't know how the surface would react. Put the ASTs at 8F/10R, keep in mind they adjust rebound only. We use to run 12F/10R, but after talking to John Wag from AST-USA he highly recommended not to run full-stiff and to run softer on the front to get the car to rotate better since it doesn't have a rear bar. A little testing at an unknown road in Tennessee and the local event proved that it definitely made a difference with turn-in understeer and the car would rotate around the turn better on throttle. After our first runs we quickly realized that over-steer was a big issue on this course. Brought the fronts up to 10 for 10F/10R, still sliding too much, brought the front up and rear down for 11F/9R and settled on that.

On to tires! We were fortunate enough that it was a warm day, which RS3s love....

amb temp - 77*
Tire temps, Inside-Center-Outside:
in grid: F - 82-95-93 R - 86-88-92
4 runs, F38psi/R36psi F - 120-135-135, R - 125-140-135
8 runs, 35psi F - 125-140-140, R - 130-145-145

I think an auto-x miata will see hotter outside temps vs inside. You're rarely not making a transition and the outside is loaded a LOT. My biggest finding was actually tire pressure, go figure. I use to run the RS3s at 32/30, but that was on my stock R-package suspension. Ever since I got the Xidas I ran 38/36 based off Hankook's recommendation of 40psi being the ideal pressure, +/- 2psi based on weight. I think I'll drop down to 34/32 the next event. I couldn't get the rears low enough between runs, sliding around so much I suppose. Like my co-driver did in this fancy tank-slapper at the end of the run that was CLEAN!
http://youtu.be/idCeLW5JqBs


Also, my 94 is for sale!!!! http://greenville.craigslist.org/cto/3694124095.html I'm moving onto an NB that I couldn't pass up :) (it's already won two National Tours in STR)

kung fu jesus
03-26-2013, 08:35 PM
Hey Marcus! I thought that was you.

Is this thread sort of a performance logbook or are there questions to the adjustments you are performing?

Either way, I think that may be why no one has responded. It is an interesting read, though. Thanks for taking the time to post this up!

flier129
03-26-2013, 11:12 PM
Ah so this is where you're hiding Steven.

Yeah, it's mostly a shared logbook lol. A ''here's what worked for me'' thread.

Boris
03-26-2013, 11:58 PM
2 questions.
How do you get so much camber out of your car especially in the rear ?

I'm about to run the RS3's for the first time (until now I've ran the Kumho XS's), why did you not run a lower pressure to help them to heat up ? Where they rolling over ?
I'm in STS so 7.5" rims for me but still trying to get as much info on the tires as I can.

flier129
03-27-2013, 12:07 AM
I'm really low, 4''F/4.25''R for the pinch welds. So I've got a lot of static camber.

I just never changed tire pressures because th setup was working and we were winning, locally at least. After getting some measurements I'll definitely be running lower pressures.

Depending on the surface(concrete) it's taken off a lot of chalk on the side, right to the little roll over line. I don't know what else to call that little line. You'll like the rs3s, loads of grip and they love the heat.

kung fu jesus
03-27-2013, 07:09 AM
Softening the settings on the dampers makes sense. Too stiff, for the speed/transitional of autocross, and it is overriding the mechanical grip. Sort of less is more with those springs.

BTW, I have a buddy in ATL interested in your car. I will push him a little more. His name is Bryan.

flier129
03-27-2013, 04:02 PM
Yeah, the Xidas are pretty damn nice. It's amazing that you can feel the difference in one adjustment.

Awesome! It's posted up on mx5atlanta actually. I've had a few inquires, one serious guy from Ohio, but nothing solid yet. It should sell within the next two weeks without a problem, then I'm off to go pick up the NB.

Boris
03-27-2013, 05:20 PM
I'm running 4.5" front and back yet the alignment guy still struggled to get 1.7* camber in the rear. Maybe he just sucked.
I'd like to run a bit lower but with the Koni/GC setup I need a bit more travel.

I see you are running zero toe all round, ever play the toe out/in game ?

kung fu jesus
03-27-2013, 08:20 PM
When an alignment shop can't get enough camber, it's usually lack of experience or stretched eccentrics.

flier129
08-08-2013, 08:47 PM
I'll be updating this soon with progress on my NB. I've been running the BFGs for the past handfull of events and they seem great in some situations, then crazy in others. Adding some front camber because I feel like it'll eliminate some front-end wash-out on exit and because the pyrometer is telling me too :)

Here's me being slow at my latest tour:

http://youtu.be/i8XqzxOiT8Q