Jump to content

Moonshine V2 - We're packing up and going to #GRIDLIFE

Recommended Posts

Since I'm finally joining the NASA TT fray, figured I'd introduce the car. For anyone familiar with Miata's and the formula to make them fast, nothing new going on there. The only difference being this is my daily driver, so I'm going to compromise outright performance for a bit usability and keeping it fun on the street. I work from home, so I have a little leeway vs someone who spends time in traffic every day.


The build, once complete, should be an absolute riot. The car is a 97 Touring (PEP, minus Torsen) with ~52k original miles. Bought it three years ago come February with 22k miles. It was at a Ford dealer in my hometown (Mobile, AL), but with heavily oxidized paint and a literal rats nest in the intake box it was clear it didn't spend most of its life in a comfy garage. After some baseline maintenance and swapping over coilovers/wheels from my previous 95 Base it's been 30k (mostly) problem free miles on the street and at autocross/the track. 


Car as it sits.

+5 JacksonRacing Header - Enthuza OBD-II cat - RacingBeat Powerpulse catback

+1 HPS Intake modified to fit NA

+7 Koni Sports 600/450 with RacingBeat front sway bar and choice of 11 or 12mm rear sway

+3 4.1 Torsen

-3 205 RC-1 or -5 205 VR-1


= 13


Weight is currently unknown, but being a full interior street car with OEM hardtop, 4 point bar, stock seats, A/C, power steering/windows/mirrors, etc my guess is it's probably over min comp weight WITHOUT me even in it. 


+3 MS3 Basic (Going in this weekend. Plan is to run 93 on street and e85 for TTE to hopefully hit my 141whp limit based off 2335 comp weight. May require RacingBeat header, test pipe, playing with intake lenght, etc, but is certainly doable)

+3 6 Speed (5 Speed + 4.77 final drive is a common TTE Miata upgrade. 6 Speed with 4.1 actually gives slightly shorter gearing, but maintains a usable highway gear)


Alternatively I could run full aero. I already have a trunk lid with Blackbird spoiler, but that requires a lot more compromise. 1000/500 springs, stock sways, OEM header, swapping aero bumper/trunk, etc. It'd be the faster setup paired with a 4.3 or 4.77 final drive, but isn't really what I'm aiming for at the moment. 


Looking forward to meeting the group and trying my best not to be a moving chicane.

Here's a lap of Moonshine and I gettin' it at Harris Hill a few months ago. Two year old dead ZII's, wonky alignment, open diff, and less than optimal line didn't make for much of a good lap time, but good fun none the less. 



Link to post

Welcome to TT madness! E can be pretty competitive for sure.


140 whp on a stock 1.8 motor and no VVT? That's a pretty lofty goal!


IMO, 6 speed would not be worth it for TTE. I don't know of anyone who is doing this in E on purpose (as in, it came with their car but they didn't swap it in.) 4.30 Torsen is a great setup on the 5 speed, and taking points for an extra gear is just silly. The 6 speed is also notoriously clunky and a lot of people have issues on track with them. Going to a 4.77 also probably means you'll be bouncing of the rev limiter a lot or adding shifts you wouldn't need with a 4.30.


E is also a place where you can either go for aero or power with your points. Both have been done successfully, but setup is key.


You can also look at dyno reclass options. Granted, the reclass you get will be less favorable weight:power than the class limits, but that frees up all the engine mod points for other things. There's a few pre-baked dyno reclass for the '97 Miata in the TT rules.


See you at the track!

Link to post

Welcome to TT madness! E can be pretty competitive for sure.


140 whp on a stock 1.8 motor and no VVT? That's a pretty lofty goal!


IMO, 6 speed would not be worth it for TTE. I don't know of anyone who is doing this in E on purpose (as in, it came with their car but they didn't swap it in.) 4.30 Torsen is a great setup on the 5 speed, and taking points for an extra gear is just silly. The 6 speed is also notoriously clunky and a lot of people have issues on track with them. Going to a 4.77 also probably means you'll be bouncing of the rev limiter a lot or adding shifts you wouldn't need with a 4.30.


E is also a place where you can either go for aero or power with your points. Both have been done successfully, but setup is key.


You can also look at dyno reclass options. Granted, the reclass you get will be less favorable weight:power than the class limits, but that frees up all the engine mod points for other things. There's a few pre-baked dyno reclass for the '97 Miata in the TT rules.


See you at the track!


I'm hoping 140whp won't be that much of a long shot. There's a thread from a few years ago where Emilio made 135whp on an unopened NA8 with MS2 on e85, intake, OEM header, and exhaust. Then 138whp on a tired NA8 with the same and RB header. It'll require having a healthy motor (which I believe mine is, pulls much better than my tired 95 did on same setup), right setup from intake back, and a good tune, but I think (hope) it's doable. We'll see, I'm not gonna get too hung up on it since it should be a whole lot more fun with MS3 and proper tune than it is now on stock ECU.


The short gearing could certainly be track dependent, but is generally an advantage from what I've seen. Barring all but the tightest hairpin it eliminates the need for 2nd gear and should put you right in the meat of 3rd for slow corners. At the very least I'd like to swap my 4.1 final drive for 4.3. 4.1 is awful gearing for such a low power car with the aero of a brick. 


Thanks! See ya'll soon.

Link to post

Emilio put the 'PTE/TTE formula' on Miata Turbo a few years ago. His formula is a proven way to go.


For TT/PT builds somethings are worth the points and somethings are not.

Tires are always worth the points. Hooser SM7/R7 are #1, Toyo RR's are OK. If your going with RC-1's you really need to be 225s on 9s. The 205 SM7s and RRs are best on 9s. Get a tire trailer if you're driving to the track.

With a Miata, suspension is worth the points. Moving to Xida's 800/500 is worth the money and will be very comfortable on the street. You may want to move to a 14mm rear bar. Emilio has an adjustable one.

The MS-PNP will give you more power and raise the rev limiter as long as the I/H/E is done well and you get a professional dyno tune. I don't know what an HPS intake is, but check your Intake temps via the ECU to verify you're not getting a lot of hot air in. The stock intake is really pretty good.

A 4.3 Torsen II is best, but the 4.1 will be OK.

The stock brakes are fine as long as they are working properly with fresh fluid and the right pads. If I were driving to the track I'd probably go with something like a DTC-30 that has a wide temp range. Fresh NAPA rotors, no slots or vents.

Before going to the track, make sure your cooling is in order. A stock radiator, as long as the top is dark black, is OK. Emilio's CSF is better. No leaky water pump or hoses. Fresh distilled water and Water Wetter.

New front hubs/bearings and carry a spare. Double check the rear bearings.


Poly bushings, light weight flywheel and setting the timing are all points free mods and worth doing. (and you really must have a strut tower brace for bling  :biggrin: {see the classifieds})


DATA IS YOUR MOST VALUABLE POINTS FREE MOD!!!!! Race Chrono on your phone with a 10hz GPS is good, an AIM Solo is better.

Your second is a good alignment. See the 949 website for specs.


I'm with Shuko, the 6 speed is not worth the points in a Miata. It really doesn't improve any of the shift points. Its the same range as the 5 speed, so you're just shifting more. Go to Vimeo and check out some of Chris Kerns early videos when he had a 6, way too much shifting in awkward places. He moved to a 5 speed later. 2nd gear with a light weight flywheel is a blast out of slow corners. We can pretend we're a Mustang or Vette and feather the throttle instead of the usual flat to the floor immediately.


Bottom line, you can have a lot of fun in the car as it is and with some additional mods. But ...

you won't be at the top of the class without getting to weight. That means stripping the insides of the car, loosing the A/C and PS. Removing the soft top if it's still in.

Spending a lot of money on parts without getting to weight really won't get you any faster.


In fact, more money on track time/instruction and less on parts is the proven way to get faster.

Link to post

Thanks for the input. FWIW I've been around Miata's for quite a bit and have done a lot of reading from the sidelines about 949's adventures in TT/PT. As far as no points general maintenance/track prep goes I'm already running the CSF with 180* thermostat, which on a nearly 90 degree day at Harris Hill never got over ~205*. In the middle of summer I may need to duct it a bit better. For brakes I'm a big fan of Carbotech/G-Loc and have no issues running the XP8 as a dual use pad with Motul and Centric blanks. With something more grippy than VR-1/RC-1 I'd likely need to step that up to XP10 up front, but we'll see. I love the modulation of those pads and they're rather street friendly for a pad that can handle track work. Anything with corrosive dust doesn't really work for dual use. I actually had to replace both a front and rear hub since owning this car, but definitely a good reminder to have spares around and stay on top of keeping up with their hours and any play in the bearings. I have already deleted the soft top as I rarely go topless. I like the Miata more for how it drives and how cheap everything is vs the fact it's a convertible. I also wanted to offset running both a roll bar and OEM hardtop. For alignment I've been running the 949 dual duty numbers for years, although they keep moving. Currently I'm at -2.5F/-2.0R, 3 caster, and 0 toe. I'd actually like to get corner balanced once suspension is finalized. 


I've got a good idea of how to build the bleeding edge TTE Miata, this isn't it. This is going to be (hopefully) fast enough to have some fun going toe to toe regionally and still be a fun street car (i.e. no stripped interior, retain A/C). Maybe not a winner, but fun and still capable of mixing it up. The HPS intake is a whole lot like the K&N. Aluminum and a bit too long. I'm actually going to trim it down and should be right around 22-23", which is on the upper end of the suggested 18-23". As for heat I've done a good bit of monitoring intake temps via TorqueApp. Obviously cruising on the interstate at 4000rpm's is a lot different than lap after lap of WOT, but what I've found is this "hot air intake" actually runs a few degrees cooler than the stock setup both headlights up and down. Headlights up it was a mere 6 degrees above ambient last weekend, granted it was rather cold last weekend, but this was A/B testing and the stock setup was hovering around 10 degrees above ambient. Pretty much a wash. The plastic of the stock air box and crossover tube heatsoaks pretty badly. Ideally I'd like to build an isolation box and maybe even use a NACA duct in the driver side headlight, but that's not a priority at this point in time. The priority is hitting every event first and reaching full prep (for this project at least) second. 

Oh and I run RaceChrono for data, good stuff!

Link to post

It would seem I'm vastly overestimating weight based off listed curb weight, which assumes full tank of fuel, spare tire/jack tools, etc. The below is nearly my car to the T, minus the fact I run hardtop with no softtop, which should be a wash. Makes me feel a bit better, just need to go get the car weighed to confirm and go from there. I sit pretty steady at 185lbs, so need to get down to 2150ish.


"For what its worth

my 97 miata str car w/ diff, ps, pl, pw, ac, cruise
-racing beat i/h/e
-hard dog ace bar (45lbs)
-koni yellows with rb springs and nb top hats
-15x9 6uls with 225/45 rs3s
-half tank of gas

weighed in at 2170 at nj pro solo"

Link to post

Finally got the car started and idling on the MS3 Basic last night. Picked it up second hand fairly local last month, but PO never installed it and when he bought it from MSLabs it had spent a few months in anther car. Apparently that car was turbo'd and nothing like OEM because boost control was configured and it was set to crank on Miata 99-05 settings. Have a friend with a 96-97 MS3 Basic and his oldest project restore had the base settings I needed. Fired right up at that point. Only problem now is my DB37 apparently isn't working right as my LC-2 isn't getting power. About to start fighting with that so I can get to street tuning. Had someone weld an NPT bung to my intake last night, Innovate DB gauge installed in driver side tombstone vent, GM IAT spliced into MAF harness, passenger side torn apart for install :P so everything else is squared away. Spent the morning/afternoon respringing from 450F/350R to 600F/450R, which with RB front bar and 11mm rear gives me 58.2 FRC down from 60. The 949 package (800/500 RB front / 14mm rear) is 58.5 for perspective. Previous setup suffered from understeer pretty much everywhere, most frustratingly on corner exit under power. Unfortunately I misjudged buying 600# 7" springs and can't quite get back down to 4.5F/4.75R measured at pinch weld. I could lower the circlip, but then the perch will just hit the UCA. Yet another reason to go ahead and get Xida's. 


And if you think I'm travel limited in the rear, I got that covered. 1" ISC top hats in the rear gives them more travel than the front. In fact, the front is the limiting factor on going low. Doesn't really eat up droop travel because with everything bolted up the Koni's have way more than they could ever use. Also checked clearance without the springs installed and the 36mm (rear) bumpstop engages before tire to tub or UCA to tub, although just barely. Front bump stops are trimmed to 30mm (as per Shaikh) for a little extra travel.

Link to post

MS3 Basic install complete as of ~1am or so. Used the wee hours for some street tuning on empty 130. Hit pretty much every cell and the car is pulling soooo nice. Unfortunately it's a little rich because Tunerstudio is reading about .7 leaner than my DB gauge. One of this morning's projects is sorting that out and mounting in stock location to easily swap back to OBDII.


The low/mid range torque is going to have me giddy for a while. So fun. Also digging the soft fuel cut 100rpm before rev limit, which is now bumped to 7200 from 6850.

Link to post

Rewired to finish up final install and get everything nice and tidy. Moving the DB gauge to its own ground has it and Tunerstudio perfectly in sync for AFR's. Changed the AFR table up quite a bit last night because the DIY basemap is pig rich everywhere. Just went out to do some autotuning and yep, still giddy. Maybe more giddy. Table needs a little manual cleaning up, but was able to hit just about everything that gets used. It's pulling extremely well on 93 and I swear it feels smoother pulling through the rev range. Not K series smooth, but smoother than it was on stock ECU. If only BP's were Honda smooth. Watching timing advance on the stock ECU with TorqueApp I know it defaults to right around 20 at WOT, so I'm guessing that plus closer to ideal fuel is the reason for the season. Can't wait to get dyno tuned and run some corn.













Link to post

Are you using FatCat's suspension design spreadsheet to come up with FRC?


Also, do you plan to hit a dyno before running with NASA, or just go points only?


1. Yes, but only to compare against a known setup (Xida 800/500, RB front bar / 14mm rear bar) and of course the setup I came from. 


2. Points build. For first event I'm not even bringing my RC-1's so I'll actually have 5 points to spare. May run my Blackbird spoiler for fun. 

Link to post

Went over my AFR table last night and made some changes based on research, logs and (hopefully good) logic. Leaned out my cruising cells 3000-4300 a tad and then blended a bit more around them. Also changed WOT to 12.8 across the board. VE Analyze made quick work of "fixing" my VE table to match the targets. Before the car felt strongest midrange and then fell flat a bit, now it seems to pull until it starts running out of breath at 6800 or so. 


Played with launch control just for grins since it works out of the box with the clutch switch. It takes a hilarious amount of revs to get a good launch with so little HP.

Link to post

Continuing to work on the tune, actually working on straight e85 at the moment. Having a little trouble dialing in low end torque compared to 93, but that might not be an issue since I have no intention of using e85 for daily use. 93 e10 can make really good numbers for everyday use and actually felt better driving around on the street, virtual dyno confirmed it. One thing I'm noticing is BOTH are getting choked down after 6000rpm and ~12.6-8 AFR. Haven't had a chance to make changes to AFR targets/VE and test, but I'm going to try adding more fuel after 6000rpms, but I don't know that anything is going to help too much. I believe part of the issue is either the JacksonRacing Header 4-2-1 design or Enthuza OBD-II high flow cat or some combination of the two and of course air/fuel. Slapping a test pipe on is easy enough and I do eventually want a RacingBeat 4-1, but for now this is what I got. Have a new WIX fuel filter going in tonight just in case as I've been running e85 all week. Don't believe that's an issue at this point, but worth taking care of.


HPS Intake - JR Header - Enthuza OBDII cat - RacingBeat PowerPulse resonated catback


Red - Stock ECU on 93/MAF

Green - MS3 on 93/MAF Delete

Blue - MS3 on E85/MAF Delete


EDIT: Went back and added AFR data for the MS3 runs. 93 is running 2-3 tenths richer at the very end, where it makes more power. So it seems mo' fuel is the answer to retaining some hp/tq out that far. The stock ECU is probably running pig rich at 11.8 or so and making more torque, so going to start working towards that and see what happens.


Ugh, bad screenshot is bad. Starts at 3000rpm and the breaks are 4000, 5000, 6000, 7000 chart ends at 7200.


Link to post

Getting some use out of the Forza livery editor  :biggrin: Just ordered reusable vinyl panels in this configuration. Thought I wanted different coloring, but keeping it simple looked far better than introducing more color with everything I tried. Will put stickers on reusable vinyl too.



Link to post

Welp, after a whole crap ton of street tuning it appears my fueling has hit a ceiling on e85. I was under the impression NA8 injectors could handle e85 in a N/A application (https://forum.miata.net/vb/showthread.php?t=516323), so I'm either doing something wrong or something is jacked up in my system. After 6000rpms I can't keep my AFR's in the low 12's and they creep up to 13 by 7000rpm. Low 12's is where it's making all the power, so right now I'm going to hit whatever I hit at 6000rpm and then flat line. Bugger.

Link to post

If running true e85 you will be using 33% more fuel than 93, at 140whp and 85 duty cycle you will need 300cc injectors. https://www.rceng.com/technical.aspx. If stock injectors you probably have 250-265cc. Good luck


Duty cycle was pegged. Need FPR and/or bigger injectors. Went back to 93 tonight and got fuel/AFR's dialed in super quickly, funny how that works when you're staying below 80% duty cycle. Will probably switch to a dyno reclass once I'm tuned if it makes sense to do so. Don't have anything to lose when I'm going to be well off class power to weight ratio anyways.


That or pick up an NB.

Link to post

Recommend bigger injectors and/or lower ethanol blend (to perhaps e60 -24% more fuel)


Bigger injectors/FPR = points. I agree that's the correct way to do it though. Lower blend might work, but I think it'd have to be closer to e40 as the fueling numbers seem to be a little conservative. I added 35% to my required fuel for e85, which should actually be e79 in Austin right now, and it still had to dump fuel into my 93 VE map. Maybe that's simply because it was 95+% duty cycle from 5000rpm onward. If I come back to wanting to run e85 or a blend I'll go ahead and install a continental flex fuel sensor to make it easier. 

Link to post

So turns out Moonshine apparently has as healthy an appetite as I do. We weighed in at 2510 with, I'll call it 11 gallons of fuel (12.7 gallon tank). Right between 3/4 and full mark after first session. Removing passenger seat for 40lbs and burning off some fuel for another ~40lbs gets things looking better, but still far from light at about 2430. I'm thinking the TTE base pre-approved reclass will be the way to go for now and have plenty of points to play with. Get dyno tuned for as close to 127hp as I can possibly get on 93 and shed a bit more weight to get closer to 2375. Lighter driver seat would be obvious, but that's pricey and adds up quick unless it's a 3-point compatible seat (Elise, Marrad, etc). If going with 6-point I'm going to need a new helmet, hans, etc. Power steering is only 10lbs or so and I actually like the feel on NA8's. A/C is staying. Could drop the Racingbeat muffler at the track for a turn down for a whopping ~16lbs and Spec Miata angry swarm of bumble bees. Not sure how much lighter Xidas are than koni sports, but there might be marginal savings there once I go that route. All in all, getting light means $$$ or ripping stuff out that I'm not sacrificing on my daily, so going to do my best to get to 2380-2400 and not worry about it too much.


Alignment. Was getting a lot of clunking after the launch and when attacking curbs. Probably time for new alignment bolts and a race shop corner balance/alignment + mega torque on the front LCA bolts. All in all the koni sport 600/450 setup actually felt pretty damn good. After weighing the car I evened up the perches because my corner weights were jacked, like 700lbs on front left, 600 on right rear, and 530-550 on front right and rear left. LF and RR were set equal parts higher than their RF/LR counterparts, so I dropped them down to even up the perches at all four corners and raised the front to get ride heights back in line. All four corners are at slightly different heights, but still pretty close to where they should be. The change was immediately noticeable as the car no longer plowed through right hand turns and was actually willing to let me get on the throttle earlier. 


Gearing. I at least need the 4.3. 4.1 is killin' me out of the slow stuff or I'm just fat and down on power. Even carrying similar speed on to straights TomTom was walking away from me. 4.77 would be the bees knees. 


EricJ nailed it when he said I should run 225 RC1's. Hell, I'd run 245 RC1's if I could fit them in NA fenders on a 15x10, but that's getting VERY aggressive on the fenders or breaking out the sawzall. Nope. I'd definitely be winning stance wars if nothing else.


There's only so much time and money between events though, so current goals are new wheels for my RC-1's and dyno tune. Maybe find a 4.3 diff carrier and swap my torsen over. Might go ahead and get 15x9 6UL's so I can slap 225's on later, or 205 purple crack if it comes to that.

Link to post

I'm not very good at the maths, but in the quest of achieving the best balance I can on my current suspension setup I've been tearing through numbers based on what Shaikh at FCM originally recommended. Assuming OEM tophats he had me use 36mm FCM stops front and rear, with the fronts being trimmed to 30mm. Works great at anything ~5" pinch weld or higher, not so much below that as the rear stops end up engaged immediately by about 4.5". To that end I threw my 1" ISC top hats back in, problem sovled right? Wrong. Despite being a 1" top hat I'm measuring an actual gain of 19mm (3/4"), but even that 19mm gain gives the rear a boat load of travel before engaging the stop vs the front. Under full compression the rear is squatting way more than the front, which means understeer. Sure, I could throw more rear bar at it, but that seems like a band aid vs doing it correctly.


So to even get close to fixing this I would need to remove the 9mm spacer up front AND trim the bump stop to 20mm. That will still have the rear squatting more under full compression and likely bury the front tire into the fender (unusable travel). Add a 9mm spacer (for a total of 18mm) in the rear and things are back to the original numbers. At this point we've gained 10mm of travel in the rear total. So, instead of all that I'm just going to swap the rear top hats back to NA top hats, trim the front bumps to 20mm and rears to 26mm from 30/36 respectively. That's gaining nearly a half inch of travel at both ends while keeping all the numbers in line for initial bump stop contact to full compression while retaining the 9mm spacers to keep the koni's from self destructing. 


Hopefully this will go towards fixing some of the understeer I was getting at MSR-H, which was limiting corner entry and mid corner speeds and making it hard to rotate from mid corner to exit. I'd like to be more neutral to slightly loose in the name of building and maintaining momentum. 


The real fix is XIdas, but that's not in the budget yet.

Link to post

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Create New...