Hi Guys, New owner and Track car Build

[timk]

I use my car as a daily as well as a track car and it's pretty quick and easy to swap out just the front pads, maybe give this idea some consideration?

Also I had an absolute blast at track days with a gutted out but standard NB, it was pretty quick too!

Speaking from experience I think the key to having the most fun is to keep the time and monetary investment low.

Cheers

[Racing Logic]

I use my car as a daily as well as a track car and it's pretty quick and easy to swap out just the front pads, maybe give this idea some consideration?

Also I had an absolute blast at track days with a gutted out but standard NB, it was pretty quick too!

Speaking from experience I think the key to having the most fun is to keep the time and monetary investment low.

Cheers

I totally agree. Just about every part I bought is second hand. This is my post GFC track car
This was my last track car. Just a pair of my TE37 race wheels and tires cost more than my entire MX-5 so far! Damn global recession.



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[Racing Logic]

Hey mods, do you want to move this to the Garage?

I ripped out all the smelly old sound reading and carpet backing, took out the carpets and gave them a wash. Next it's time for the seat "foam-ectomy" to get my 6'2 frame to fit better.

New tires KU36 205/50/15 are now getting fitted to some bronze Gram Light 57S 15x6.5 +38 that I picked up from another member.

I'm looking at getting more camber with some new offset bushings. Anyone have a favorite brand?

[Okibi]

Moved. Welcome

[Hellmun]

I've run DS3000's before (Back in 2007 though) and while they are survival champions (Never faded even when on fire) they weren't actually that high friction compared to a Hawk blues/Carbotechs. I found they had poor initial bite and really needed pressure compared to other pads. I found the Carbotech XP12's were significantly better in initial bite and modulation. Plus they're a lot cheaper, DS3000's were $430 last I checked, 949 can get you Carb's for under $200 with the current dollar. I think Deckspeed even retail the carbotech's over here but I don't know how much they charge.

Getting a BP to 180-200kw isn't that hard, the stock SP manifold and turbo will do about that with a exhaust, intake and enough fuel. Plus there's plenty of readily available other upgrades to keep going. If the only tyres your planning on running are KU36's though don't expect 1st or 2nd to hook-up at all with that power level, especially with only 205's. Hell 3rd gear is still producing wheel spin on low boost for me if the road isn't perfectly smooth. I'm still waiting to run my car on the track with 225/50/15 V70A's to see if I can use second at all.... Can't really compare the power:weight directly with the Evo either. Mx5 has little download, short wheelbase and no intelligent 4WD to help so they're little animals at this power level, it'll float and dance around a lot just in a straight line. Really couldn't recommended enough going for a ride with someone in the 200kw power range to get a feel for it. The SR20 has awesome potential but it'll add cost and you'll still have to deal with the other driveline issues (gearbox/halfshafts etc) the BP can already wreck on the track without the added complexity of the swap.

[charlie_91]

Come up to Brisbane and take my car for a quick drive to see how u like the power. On nt01's I don't spin 2nd or 3rd and I'm at like 230rwkw ATM. Of course in the wet it's a different story :p.

Especially at the track, you'd be surprised how tamed it is coming out of corners. Not violent at all if you ease onto the throttle but if it does get u sideways its very predictable.

[Hjt]

Nt01 are a brilliant soft tyre.

[Racing Logic]

Thanks for the advice guys.

What camber bushings are you guys running?

[Hellmun]

I've got the super Pro's but I believe there are equivalent cheaper alternatives now from UK/US. I think the supers are up over $600-$700 now.

I wasn't alluding the car wasn't controllable Charlie but it's not going to behave like an EVO. Just trying to give a little perspective that even at the 180-200kw power level it will be a handful, is in reach of the original motor and might save money better spent elsewhere than going down the SR20 path. My car made 222kw atw on the deskspeed hub dyno on high boost and with 205/50/15 KU31's it's barely hooking up 3rd in a straight line. The car is awesome fun and hasn't lost the chassis balance it had but we have issues going high power the EVO's don't. Poor wide tyre choice due to limited height, lack of proven aero improvements, lack of drivetrain reliability (go look at some 2B prod sports cars and see how often they go through 6 speeds or now run a old 5 speed skyline box).

[Racing Logic]

Yeah guys I'm expecting to spin all over the place. I'm used to being able to put the power (not that this car has any) down so early in the Evo and just let the diffs pull me through the corner.
I definitely need more camber on the front of this little thing. I'm at 1.5 front and 2 rear

Tonight I'm putting on my brake and clutch lines and just giving everything up front a good tighten up.

[toppertee]

This set up seems to work for the mx5. I found it much better than my last set up.

It's from 949 racing in the states.


Quote

SuperMiata / 949Racing's Miata set up tips

All content on this page copyright Traksport LLC 2012

Disclaimer: Doing anything to your car as described on this page is dangerous, might kill you and and everyone around you. IOW, don't sue me if you mess your car up and crash.

THESE SETTINGS MAY NOT BE STOCK TIRE, STOCK SUSPENSION, CASUAL STREET DRIVING OR TIRE WEAR FRIENDLY!

Alignment

These are the maximum performance settings I use to set up a Miata to generate the best balance of turn in, steady state lateral grip, braking grip/stability and power application in competitive type driving environments The bias is towards steady state lateral grip as that is what makes a Miata fast more than the other facets of it's performance envelope.

These settings assume:

* Either factory sport package Bilsteins, Koni's or high performance aftermarket dampers
* At least a slight increase in static spring rate front and rear
* True high performance tires, not bargain all season rim protectors
* You are comfortable with potentially less high speed directional stability than the Mazda factory alignment settings may provide

Ride height

There are several ways to measure ride height. The most common are fender height & pinch weld height. If you are always using the same tire diameter, I recommend using pinch weld height as it's easier to get more precise and repeatable measurements. We always use pinch weld heights for our cars.

Measuring pinch weld height

Requires that you always measure with the same size tires. Take measurement from forward most and rearmost straight area of lower unit body pinch weld just before it curves up. If you measure frequently, a small dot of contrasting paint or other mark on your measuring point is a good idea. Our alignment numbers are assuming a ~22.9" tall tire which when loaded, will have a static loaded radius of 11.25".

Measuring fender height

This measurement allows comparison between two cars with different tires. The actual fender shape and location can vary on a 10-20 year old car so this method is less precise. You must locate the exact center of the hub and this is difficult to do accurately. If you hold the measuring tape next to the hub you induces an error because the tape will not be 90° the ground plane. The fender lip on an unrolled fender can be 3/16" thick so to different people will often interpret the exact point differently.

Other important stuff
These settings work best with the factory Torsen or OS Giken differentials. Tighter 1 or 1.5 way clutch type diffs may require -1/16'' total front toe to help the front turn in off throttle in autocross situations. Ideally you will change the front to rear spring rate and anti-roll bar differential (FRC) biased towards the front. The OE FRC is only slightly front biased but the lower front camber serves to keep the car more or less neutral. I have found that setting the front camber from equal to -4 ° more than the rear provide best grip and lowest lap times. Doing this on an otherwise stone stock Miata will result in an excessively loose, tail happy car so don't !

Testing
To maximize the performance you need to test, test, test. That means, same tires, same driver, same conditions, change on thing at a time. Record tire temps with a probe type pyrometer (no lasers!), lap times, tire wear patterns, tire pressures and most importantly, driver impressions immediately after run. There is no "best" alignment for every condition, only the"best" compromise that suits your needs. The more you are trying to squeeze out of the car on given course or track on that day, the more you have to test, record adjust, repeat. You shouldn't expect to be able copy these setting verbatim and have it turn out 100% perfect for every possible car, driver, course. That's why race teams have highly skilled full time engineers constantly tweaking the cars to milk more speed out of the car.

Most DOT R compound race tires will develop their peak steady state lateral (cornering) grip at camber, toe and pressure settings that won't necessarily show even tread temps or wear. Generally when temps are even you are very close so the pyrometer is your friend. I usually shoot for tire temps 10~15* hotter on the inside than the outside. Don't assume anything when reading tire temps or any other measurement. Drive it hard, pay attention to the car and experiment. Clocks don't lie.

Please don't ask me how your tires will wear because: A) I don't know. B) You shouldn't care if you are considering using these settings as a starting point. In practice, when the suspension is right, my race tires wear absolutely perfect, only need about 30psi hot on 8 or 9'' wheels and the car is fast.

SuperMiata DD Alignment
>=12" front ride height (measured hub center to fender)

>=4.5" front ride height measured at forward most straight section of pinch weld with 205/50/15 or 225/45/15 tires

Front camber: -2° (or as close as you can get to it)
Caster: >4°
Front total toe: 0

Rear camber : -1.8°
Rear total toe: 0

SuperMiata Race Alignment

<=12.0"

3.75~ 4.25" front ride height measured at forward most straight section of pinch weld with 205/50/15 or 225/45/15 tires

Front camber: -3° (or as close as you can get to it)
Caster: >+4.5° or max available once you reach camber targets
Front total toe: 0

Rear camber : -2.6°
Rear total toe: 0

Variations and extra stuff

The Miata seems to work best with about .25" positive rake (rear higher) measured at the pinch welds without driver in car and about 1/4 tank. It seems the the roll center axis doesn't like to be too far out of sync with the roll centers. In general, you can lower the rake to increase rear grip and improve transitional stability up to the point that the rear suspension begins to bottom. Lower the front to increase front grip and turn in response, again, until it begins to bottom the suspension excessively.

Sway bars (anti-roll bars)

Disconnecting the rear sway bar on a lowered Miata allows the inside wheel in a turn to droop further. Since the inside front with swaybar still attached will not droop, rake changes. This means the front stays low, the rear jacks up in a turn. The effect is slight but it changes the roll axis, camber gain and a few other things. For autocrosser, this compromise is usually worth it as it will greatly reduce wheel spin and reduce oversteer during low speed transitions. For track use however, this will usually result in terminal understeer that will have you pulling your hair out trying to get rid of. In short, if you can get your autocrosser to work with the rear bar, keep it hooked up. For track use, save yourself the headache and leave it on.

In general, the Miata likes a much stiffer front sway bar than stock, on the order on 3-4x more rate. We usually end up with a 1" solid or 1.125" hollow assuming 7" wheels and either EHP (Extreme High Performance) or R compound tires. For autocrossers, usually the OEM 11 or 12mm or sometimes nothing. For track cars usually 11, 12 or the 14mm MazdaSpeed bar. We have yet to find a car that needs more than a 14mm rear bar.

Toe

Miatas over 180whp or so can add +1/16~1/8" total toe in at the rear to attenuate corner exit power oversteer. Autocrossers forced to run wheels much narrower than optimum for the tire width will usually benefit from 1/8 to as much as 1/4" front toe out (CAUTION, this front toe out fries your tires on the street).

Camber

If you can't get enough front camber with your NA, welcome to the club! ISC Racing offers a offset front upper Delrin bushings optimized for 7" SCCA ITA wheels but they reduce bump travel with 8" or wider wheels. The Super Pro offsets, while pretty and very well made, won't stay in place so skip those. The lower the ride height, the more static front camber you will get. This is one of the reasons we like to run the front ends as low as possible. The NB front subframe has a slightly higher roll center and more camber gain. For this reason, it is the best solution to gain more front camber and help keep the roll center closer to the CG after lowering. If your class allows the NB front subframe, do it.

Caster

More caster can help mid to low speed turn in, makes steering heavier, may increase wheelspin in very low speed turns with a Torsen or open type differential. I have experimented with low and high caster and I'm drifting back to preferring high caster settings, primarily for steering feedback at high speeds.

Supermiata Street Alignment

For most street dríven Miatas, tire wear is the most important parameter. Excess toe in or out will usually cause more tire wear than somewhat aggressive camber. The OEM alignment numbers with more rear camber than in front, are designed to induce a bit of understeer. Lawyers dictate the OEM alignment, not the smart fellows that laid out the suspension. The actual suspension geometry is designed to require greater front than rear camber. This street alignment will generally result in no increase in tire wear over OEM and possibly a reduction in tire wear if you occasionally load the tires to maximum cornering forces.

NOTE: This alignment will require either a slightly larger front bar and stock or no rear sway bar or, coilovers with front springs above 6kg/350#, or high performance tires on 7 to 9" wide wheels. On a bone stock Miata, this alignment make make the car a tony bit too bit loose (oversteer).

Front camber: -1.4°
Caster: >4.5°
Front total toe: 1/16"

Rear camber : -1°
Rear total toe: 1/8"

[Racing Logic]

Thanks for that. I'm now hunting for more front camber.

[Racing Logic]

Here are a few pics of the car, from when I bought it to now. It still need a few bits and a good detail.






Gram Light 57s 15x6.5 +36


ebay front GV style splitter. Bolted on, no self tappers on a track car

[Racing Logic]

Just a little update.

Finally fitted my braided clutch line and good thing I did too. The original one was like a distorted balloon!
Flushed the cooling system, fitted the Samco hoses and new thermostat and added water wetter.
Fuel filter replaced, looks like it was the original.
Also bumped the timing up to 14. Lets see if we can feel all that power.

[Racing Logic]

I just did the foamectomy mod on my drivers seat on the bottom and back. Fantastic! Now it fits more like a Recaro and at 6'2 my head dosent hit the roof anymore. Its still going to be a squeeze with my helmet on though. That should hold me over untill I work out what seats I'm going to get.