doward

Miller was named for the 2013 NASA Championships at (then)Miller Motorsports Park in Utah. Sonny & Miller won TTD and placed 3rd in PTD at those championships.

The car is a 2004 Mazdaspeed Miata. Before being named miller, it was an early development example for turbocharged track miatas but was eventually de-turbo-ed for w2w racing.



Following that 2013 Champ effort, Miller was immediately used as one of the first Maxxis Supermiata Cup S2 cars, as well as a typical "949/Supermiata formula" HPDE/TT trackday car.



Rules can be found here : https://www.nasaproracing.com/rules
An ST6/TT6 discussion thread can be found here: https://www.miataturbo.net/race-prep...st6-tt6-97655/

With NASA's replacement of the Performance Touring series with a simpler Super Touring ruleset, we've decided to build an ST6 car.
There are six Super Touring classes—Super Touring 1, (ST1), 2, 3, 4, 5 and 6, with ST1 being the highest performance level class of the six, and ST6 being the most restrictive.
NASA's Super Touring is a power to weight ratio class, with modifiers for certain chassis characteristics like A-arm suspension and light weight.

ST6 is an 18:1 base ratio, below what PTE used to be.
Engine swaps are allowed, provided the donor was a car that would also be allowed into the class(max power rule).

Miller's build will take the following mod factors:
18:1 class base
A arms -.7
BTM aero +.4 (Credit for base trim model aero. We will not be using a front lip, airdam, or spoiler of any sort)

Comp weight mod factor will either
Less than 2450 -.4, or
Less than 2550 -.3, depending on the power we can squeeze.

So, we're going to target 18.6:1 at 2450lbs which is 131 average whp, or 18.7:1 at 2400lbs which is 128 average whp.

Because these power figures are relatively low, they would be reachable with very modest power plants...

doward

concealer404

iTrader: (3)

Is this the car that pissed off people because the rest of the field didn't know it was an MSM?

doward

Why?
Well, the NB2 has the best OEM BaseTrimModel aerodynamics. The NB2 front bumper shrouds the most front contact patch for drag reduction. We'll do an undertray behind the bumper skin to the full extent of the rules.
Because any healthy Miata motor can hit ~131whp, we can use the lightest available Miata motor.
Because ST is average power based, picking the extra midrange of a VVT BP6D or the BP4W's slight peak power edge is less advantageous.
The B6 is about 40lbs lighter, and smaller physically, so it sits farther back in the wheelbase. The extra weight off the nose is noticeable and helpful. It should turn better than any 1.8 at the same power level.


Full build list:

2004 Mazdaspeed Miata "MSM"
-de turbo'd
-B6 swapped
A arm suspension (-.7:1)
BTM Aero credit (.4:1)
2450 at 18.6:1 (-.3:1), or
2400 at 18.7:1 (-.4:1)
205 R7 on either 8" or 9" 949 Racing 6UL wheel, depending on final comp weight.

We want to hit our 131avg whp goal on 91 octane pump gas(California's "premium"), so we'll be doing a couple things to the engine.
264/256* Kelford 203B camshafts
Toda lash adjusters to allow ~75-7800 rpm.
Megasquirt MS3
Intake/Header/Exhaust

Beyond that, the chassis/suspension will be:
900/500 Supermiata Xida Race
1.125" Racing Beat front swaybar
14mm Supermiata rear swaybar
We will convert from ELBJ to offset bushings to keep away from the .2 penalty for "modified, adjustable, or altered control arm ball joints"
Energy Urethane control arm bushings

OEM Sport brakes
G-Loc R12 front, R10 rear
Supermiata stainless brake lines
Motul RBF600 fluid

Supermiata tuned OsGiken LSD
4.77 or 4.875 ratio, depending on what rpm we feel is safe/necessary with the B6.

flier129

iTrader: (7)

Yiss, dis is daewae my brudduh.

emilio700

iTrader: (3)

That was Crusher.

FatKao

What does the 4.875 r&p come out of? Unless it is a custom/aftermarket part of course.

e:
Are you going to push the motor/trans back till the head almost hits the firewall as well? Seems like it could be a lot of money for minimal gains...but allofit.

emilio700

iTrader: (3)

Aftermarket. It was the last one sold by Mazda a few years ago. Maybe they have them again, dunno. B6 doesn't rev very high and has narrow powerband compared to BP. So gearing will be critical. It's something we spend a lot of time dialing in.
Most club level teams seem to ignore gearing.

b3d3g1

How many points for Sonny mod?
​​​​​​

emilio700

iTrader: (3)

I think the BOP will be another 200lbs

x_25

I am so turned on right now. N/A B6 in an MSM. I don't think a phrase could be more fill with herracy.

doward

A cat for you good sir.

aidandj

iTrader: (5)

Short nose crank for extra lightness?

doward

C'mon. We're not "CrAzY"

FatKao

I won't be happy unless the motor is pushed back till it's touching the trans tunnel and the shifter has some kind of odd remote linkage to use the unmodified trans tunnel opening.

ridethecliche

iTrader: (2)

Who here had that awesome quote about replacing a 1.8 with a 1.6 just to **** people off? Was it Rleet? haha.

FOUND IT!

​​​​​​​

Yeah, but the 1.6 is more revvy!

x_25

As someone who has made the choice to stay 1.6.... I really wish that were the case... The BP4W I have in my 99 beater is way more happy to rev...

Scaxx

But, the B6 is supposed to have all the revs? Do you even know miata engines, bro?

ridethecliche

iTrader: (2)

Bruhhh. It revs to the moon and back. The 1.8 is the infuhrur revving motuh.

emilio700

iTrader: (3)

Ports in B6 are tiny. Flow as ratio to displacement is inferior to BP. Even B6 FP motors (huge cams) make peak power at lower revs than BP EP motors. This is something we learned when I was helping Oscar Jackson tune and develop our B6 STL motor for 2014 runoffs.

Because of the better rod ratio and lighter reciprocating mass we plan on using a complete bone stock bottom end and spinning it to 8k at most.