As promised, Sunday turned out to be pretty exciting as well.


We were running the CCW1a layout. Very similar to CW13 in reverse, with one additional corner. I ran CCW25 here once back in 2023, which was the only time I've driven this course counterclockwise. Buttonwillow is a bit of a nail-biter in any format. There's lots of super bumpy bits, apexes at the top of elevation changes, and sections that just require ***** to go fast. The first time I ran CW13 was a hit to my ego because I was so off pace. Luckily at this point, I've run the track probably fifteen times and am pretty confident/tuned into it... clockwise at least. Counterclockwise was a total reset. The track was scary all over again

For the first session (which is a competition session on Sunday, instead of practice), we were gridded by top times from Saturday. I pull in and Team Mick Blue is slotted right behind me. Great. Even if I am faster, now they're gonna be able to hang on my tail and get a leg up on me. I was still planning on trying for a decent time for gridding, but I knew I wasn't going to be able to run ***** to the wall on the fresh course layout. I didn't have much time to worry about it, we got sent out and I had to focus on myself. I set a decent, mildly conservative pace on our first hot lap and watched the multicolored E46 in my mirror drop back a bit. Alright, cool, he's taking it chill and warming up too, I'm not gonna focus behind me too much. Next lap, the bimmer starts getting much bigger in my rear view. He wasn't warming up, he was giving me a gap. F*ck, lol! After his first hot lap, he went for a cooldown but stayed out on track. I, still unimpeded by traffic in either direction, upped my pace a tiny bit over my first laps, and felt pretty good about it. The session ended and I pulled in and checked times. 2:11.598 for me, 2:09.957 for Team MB. Jesus! I knew there were a couple sections where I still needed to sack up but I didn't think I was that far off the pace.

Repost of my CCW1a PB lap here for emphasis. The whole section between 1:00 and 1:40 is a nail biter at full speed. Coming into that first left-hand crest (known as Phil Hill), there's bump and compression right in the braking zone as your car starts going uphill. In my car, it was violent enough that I was scraping splitter there every lap. Then the corner apex is right at the top of the blind crest at about 80mph. You can see even in my PB lap, I didn't use all of the exit. Next is the long left hand sweeper called Riverside. Later in the day, I came to the realization that I could take the whole section without lifting if I apexed in the right spot, but it didn't leave almost any room for error if the car was to go wide. I think my min speed through there was 103mph on the PB lap, so yeah, also scary. Then the following few straights and corners are filled with bumps and compressions. If you want to take the following right hander fast, you better be using the entire curb, which shunts the car quite a bit. A common practice among the fast guys running the opposite direction is to hit the curb going left and float the whole left side of the car over the dirt before landing back on the pavement. After that section, there's a couple more high speed corners then you come up to a substantial braking zone which is punctuated by a quick roller to punctuate your braking with some elevation change. Tire chirps over the crest every lap I'm not gonna claim it's the gnarliest track section ever, or that you need to be Dominic Toretto to drive this course fast, but I was at the edge of my confidence, man


I was pretty sure that I wasn't going to pull any sort of stunner and take make up over a second and a half on the second session. I did, however, know that there were plenty of places that I could be making up time. I went out with the intention of at least closing up the gap a little bit, just to see what I could do. I finish the warm up lap and go out for a flier. Feels pretty good, definitely faster and more confident through the back section of the course. I cross the finish line and look at the lap timer. Holy ****. One more flier using a tiny bit more exit on the backside of Phil Hill, then I stay on throttle for almost all of Riverside. Cross the finish line and pull into the pits before I can ruin my good fortune.



Sh*t man, I'll take that all day! I saw the 2:09.66 flash after the first lap and was reasonably sure that would put me ahead even if my transponder read differently, but I decided to get that second flier in just in case. I'm really glad I did. Didn't expect to close the gap on MB after the warmup session, let alone plunge deep into the 2:09's. That time ended up being good enough for the win. Temps shot up quick after the second session and Team MB didn't end up going out for session three, sticking to just the W2W races from there on out. I wouldn't break below the 2:11's for the rest of the day, either. Partially due to weather, partially because I didn't want to push my luck again.


Infiltrating enemy ranks. On grid for session three.


My student for Sunday was a first time track-er in a Shelby GT500. Dude wasn't super talkative, but I probably wouldn't be either wielding that much car my first time out there.

Since we knew our fastest times were already set, my buddy David and I decided to swap cars for the last couple sessions of the day. I got enough track time to familiarize myself with his 2013 Porsche Boxster, which was an absolute riot. The car's totally stock aside from a set of B16 coilovers and RE-71r's. The car absolutely rips, but is so much more comfortable compared to my car while doing so haha. Definitely not as fast as the rat-rod NC, but still quick and just so composed over all of the rough stuff. Watching him drive my car was pretty funny, haven't let anyone else take the wheel in it aside from my dad briefly. David had good things to say about my car too, like: "Cheater!"

And that's about it for the weekend. No other drama or issues with the car to note. I'm gonna give it an oil change this week and see if the oil is full of metal yet, then swap my street pads back in for the foreseeable future. There's a slight (SLIGHT!) chance I'm going to join @codrus in Salt Lake City the first weekend of August for the NASA event out there, but I'm still on the fence due to a potential family event. Mitch and I are taking our cars to the local go kart track for time attack night this Friday, then I have a couple more mods planned for the upcoming weeks. This thread will be getting plenty more updates whether anyone wants them or not hahaha.

 

UMC is actually in Tooele (pronounced "twill-uh") -- SLC is a good hour+ drive away. Awesome track, you should definitely come.

--Ian

 

Haha, I figured my last post was drawn out enough that I should just simplify the location. Did some poking around on Google Maps today to see how far it is from Park City. If I make it out to the event, I'll definitely be bringing the mountain bike as well.

I'll stay in touch!

 

Great driving man! Now you've got me wanting to setup flat shifting. Just gotta find that 0.02 to dip into the 8s!

 

Really awesome driving with a great result! Love your videos and recaps as always, and I can tell your driving is improving around this car, especially compared to your earlier videos in the same car or the NA miata. Cool to see.

 

Thanks dudes! Yeah, having flat shift enabled is a decent bit cooler than I anticipated. Really counterintuitive at first, but satisfying once you're warmed up to it lol. Feels slightly quicker as well although I haven't attempted to quantify this via any of my Aim data.

Hit the local go kart track for Time Attack night on Friday. Mitchel, @DUDELOL and his brother and a couple of the MTTC regulars joined as well. Our total "crew" was three NC's, one Rotrex'd NA8 and one EFR-equipped NA8. Fun was had. Last time I went was exactly a year ago in my NA, and before that, I hadn't been since 2022. Used to come here almost every other weekend before I put the turbo on the NA.

PB of the night on lap 2. Still experimenting with shift points on this track. Anyone else listen to the new Hives album yet? It f*cking rips.

This place was where I got my start "tracking" my NA8 before it even had any upgrades on it. It's a great place to learn car manners and is super fun in a Miata. The corners are tight and come up quickly, the road surface is garbage and slippery, and the chicane made out of plastic barriers on the back straight is tight as hell and just begging to put some scratches on your fenders.



The gang.



Sitting behind Mitchel on grid. He was borrowing Frankie's extra set of 255/40/17 RT660s on RPF1's. Meaty.



Each session starts with a couple parade laps, then they send out three cars at a time for timed runs of two hot laps apiece.

That turbocharged Volvo near the front of the pack was my personal favorite car of the night.



Mitchel and I were pretty neck and neck all night, but I had a massive advantage tire-wise. Mitch was borrowing Frankie's 255 RT660s, which have decent tread but are 4+ years old at this point. My tires were brand new seven days prior so I'm not gonna declare absolute victory yet haha. We're gonna come out to the next event here in July and hopefully Frankie will be able to make it so we can all duke it out again.

I was experimenting with shift points all night, but it seems I figured out the formula at the end of our second to last session. Managed a 43.89 on my final lap, beating out my previous PB of 44.55. Good stuff!

Only downside of the night was the situation with those barriers on the back straight. The track stewards put them there to slow cars down before the right hand hairpin dubbed "Big Monza". Many a car have stuffed it into the dirt from braking too late before Big Monza. Anyways, the barriers usually start tight and then vary in distance from each other as cars tap them and the officials reset them. Sometimes you'll come around for your second lap and one will be completely off the track and in the dirt. I think Mitchel had the honor of nailing the right hand barrier first in our group, tearing off his tire spat and side marker light in the process. Then Jack and Ryan each had their turns nailing it. Jack actually ended up cracking his splitter while Ryan's car sustained almost no damage. I joked with the guys that my car was going to make it out alive, then quickly ate my words as I nailed the barrier on my final lap of the night. Thankfully the clear coat on this car is so jacked that the minor paint cracks caused by it just blend right in.



More updates to come this week. You might've already noticed one of last week's mods in the GoPro footage...

 

Been chugging away with more work on the car since the race weekend at Buttonwillow. Little bit of this, little bit of that. The majority of my focus has been directed toward tooling with the backup 2.5. I finally hammered out my plans for this specific motor and started executing, so I'll touch on that first. Lots of fun little bits to go over, or maybe just things I personally find cool.

No smooth segue here. Just some cool flat shift noises that I also wanted to share.

So there's a few things I'm going to do differently with this "new" 2.5 I got on my hands. I decided that I want this motor ready to be tagged in as a replacement if I frag my current 2.5 before the end of the season, which I'll be finishing out in TT5 class. I gotta be able to toss it in the car and still run my current class. Ergo, this one won't be getting turned into a flaming hot high-compression N/A 2.4L build. At the same time, I'm still not completely decided on whether I'm going built N/A or turbo as a power adder for next year. Thus, while this engine is apart, I figured I'd do some poor man's bulletproofing to prep it for a turbo if I go that route.

Things that will be done differently on this motor than my current one:
-Opened up ring gaps
-47lb Mazdaspeed 3 valve springs instead of the super heavy 86lb Brian Crower springs
-2.3L Ecoboost head bolts
-Fab9 Stage 1 cams instead of Esslinger Stage 2's

So the leading cause of death on these motors when boosted is ringland failure. The ring gaps on these motors come pretty tight from the factory, and the OEM piston ringlands aren't super beefy. The horsepower number they fail at varies depending on use and who you talk to. Basically, once you're above the low-mid 300whp range, you're in dangerous ring-butting territory. E85 and a big intercooler help, track use obviously lowers that number. I've heard of street guys running these motors stock up to 340whp but most of the track crowd say that once you're nearing 300, it's a dice roll.



Well I already had the motor partially torn down so I figured it wasn't much extra expense to throw a new head gasket, EcoBoost head bolts, and new rod bolts at it ($146 total). I pulled the head last week and removed all the pistons to regap the rings. The top rings in this particular motor were within the workshop manual spec, but were really tight for boosted use. The bottom rings were a little better. Bore size on these engines is 89mm. 89mm to inches is 3.504... times .0055 per inch of bore is 0.0193"... Yeah .020" top and .024" bottom should be good enough. Used those numbers for my ring gap targets, popped pistons 2-4 in then knocked piston #1 off my workbench and onto the ground.





The piston landed on its head and sustained a small ding on the edge. I filed it down and looked at it for ages before coming to the conclusion that I'd rather have peace of mind even if the piston was ok as is. Luckily spare parts for these motors aren't too hard to find either. Ford sent these engines out with three different piston sizes, stamped "T1" "T2" or "T3" on the crown for identification. A new piston and wrist pin ring set (I sent one flying across the shop on disassembly) was going to cost me $130 new. Luckily all of my pistons were T2's, which seem to be the most common size. I found a good-looking complete T2 piston and rod on eBay for $70, and scooped that up. The new piston mic'd out exactly the same size as my old T2, at the top and bottom of the skirt. I popped it into my current rod and kept the old piston as a paperweight.

The next bit of extra security was 2.3L Ecoboost head bolts. The OEM 2.5L head bolts are liable to allow head lift above the low-300whp range. Again, not trying to be Icarus and reach too close to the sun if I do boost the motor, but the head bolts cost the same amount either way. The Ecoboost bolts are a common upgrade for the boosted crowd and said to be good for up to ~400whp according to Fab9 and some other voices in the community. They're the same length and thread pitch and drop right into the 2.5.



Ecoboost bolt on the left, Duratec on the right. Same length, perspective just makes them look different. I'm not gonna lie, I can't tell any differences outside of the thread length and bolt head height.

Final bits on the menu were cams and valve springs. I was going to have my stock cams ground by Esslinger into another set of "Stage 2's" like my current motor, but my buddy let me know he had a set of stage 1 Fab9 cams laying around that he'd give me for half the cost. The Fab9 stage 1's and Esslinger Stage 2's actually have the same lift specs (.400/.400"), the Fab9's just have a little less duration compared to the Esslingers (220/220* @ .050" vs 238/227* @ .050"). The Stage 1 cams result in peak horsepower hitting around 6,500rpm then tapering down just a bit, where the stage 2's peak just after my 7,200rpm redline. Max horsepower and torque seem to be roughly the same with either option. Mitchel runs the Fab9 Stage 1's in his car (albeit with a long tube header and I believe stock valve springs) and we're neck and neck on the straights so I think the engine's gonna be totally fine with these cams. They're already way more aggressive than the stockers.

The final bit for this cheap rebuild was valve spring choice. I've got Brian Crower valve springs in my current engine, and haven't had any issues with them, but they're absolute overkill. 86lbs of seat pressure vs the ~40lb stock springs. I did a bunch of digging and found (or didn't find) two things. No reports of people killing their valve seats with these heavy springs, and no accounts of people floating valves, regardless of spring choice, with stage 2 cams (the most aggressive that can be run with stock pistons). So I was probably fine running the super stiff BC's again, but I could easily go lighter and get away with it, even if I boost the engine eventually. Esslinger makes some 68lb springs that retail for $450 a set (compared to the BC's with ti retainers that I got for $240).

There's another option, though, for super cheap. Valve springs from a 2.3L Mazdaspeed 3 "DISI" engine will drop right into the Duratec and can be used with the OEM retainers. The Mazdaspeed springs sit at a claimed 47psi of seat pressure installed but ramp up in stiffness substantially faster as they're compressed compared to the stock Duratec springs. I got a full set of 16 from a Mazda dealership for $123 shipped.



Duratec valve spring on the left, DISI spring on the right. The DISI spring is shorter in height but still has enough compression before binding for up to .500"+ lift cams. Way more than this project will require.

Shoutout to this user from M.net for testing and graphing tons of valve spring stiffness curves. Bit of deeper reading for anyone interested: OEM Valve Spring Component Measurements - MX-5 Miata Forum




Got the head on and half of the DISI valve springs installed today. I'll finish them up next week then grab the upgraded cams from my buddy and this thing will almost be ready to go back together!




On second thought, I'll wait till next week to post what I've been doing to the car itself. Didn't expect to write this long of a post on my no-frills engine build project lol.

 

Wow, quick work. Thanks for the knowledge dump, I will definitely be coming back to reference this stuff when I help my buddy with cams on his NC! Thanks for the post.

Edit: Also, quit lying to yourself about the potential N/A build, we all know the turbo is coming.

 

Great info on the NC/2.5 engines. It amazes me how far things have come with the 2.0/2.5 in the last 5-6 years. When we had our first NC, the only forced induction option was the old FM/Cosworth supercharger and some half-baked Rotrex stuff. The 2.5 swap was a new thing, and nobody was duplicating the dyno numbers of the shops promoting the swap. So many options now!

 

Dude I'm trying so goddamn hard to be sensible and commit to a high-comp N/A but you know how these things go...

Glad to try and help out! This is all stuff that I've piecemealed from different posts on the FB groups, M.net posts, and performance MZR/Duratec forums. While I'm not breaking any new ground, I figured I'd try to consolidate some knowledge on here for other NC newbies. I think the 2.0L is the same as the 2.5 in that .400" lift (basically all "stage 2") cams are the max you can run on stock pistons while retaining full VVT sweep. Might wanna double check that, though. Either way, your buddy should be stoked when you guys do cams on his car! My stock 2.0 felt like it had a tiny bit of power from 5-5.5k and then just fell on its face after that lol. Maybe Roda could confirm my thoughts on that. With the Esslinger stage 2's, my current motor hits 3,600 rpm and just keeps pulling harder from there. It feels awesome, or as awesome as 180whp can feel lol. Sorry, I got a little carried away with my response haha.

Thanks dude! Yeah, I did a lot of reading when I got my car about the Cosworth SC and some of the OG 2.5 swap pioneers. The options 7-8 years ago seem to be miniscule compared to what's out there today. Even in the last 2-3 years, there seem to have been huge strides for these platforms being used in a performance application. The FM and Kraken turbo kits, Fab9 intake manifold, Moroso baffled oil pan for the NC are just a few examples. It's not just the NC's either, lots of people are starting to swap these engines into various RWD cars as well. That probably isn't hurting the market either.

https://fb.watch/ADR3j0RpV2/
Extreme example here but...

I'm getting too excited. This project is giving me deja vu into deep diving on BP engines when I first built the motor for my NA haha.

 

So progress on the car itself hasn't been still either. Over the last couple weeks, I've had a couple non-engine-related projects going on as well.

For starters, I sold the OEM hardtop.


At this point, I don't know how much more cartoonish I can make this car look.

My car's by no means heavy for an NC. It sits just above 2,400lbs depending on how the NASA scales are feeling that weekend. There's still a couple low-hanging fruits to shave some more weight off of it, though. The first and easiest of these was to ditch the factory hardtop for a lightweight one. The weight difference is immense, 14 lbs vs ~35, but the icing on top is that a new lightweight unit from CCP Fabrication is cheaper than an OEM one. I ordered a lightweight hardtop with a window, seals, and all the hardware from CCP a couple weeks ago for $1,937 shipped, put my OEM hardtop on Facebook for $2,400, and had someone drive out and pick it up for asking price next day. I thought I was selling mine for a fair price given the wrap was cracking and discolored but I guess I was still a little under the market. Oh well. It went to a good home and for possibly the only time ever, my car lost weight while my wallet gained some.

I was reeeeally considering ordering up the CCP fastback but CCP told me they couldn't confirm the fit with a BBFW roll bar. I was told BBFW was testing fitment but never received any emails back when I asked about it. Long story short, I didn't want to swap roll bars or inherit a project of that scope so I'm gonna run the regular hardtop for the rest of the season (can't run the fastback in my current class anyways). Then maybe next season, I'll rig up some sort of ghetto fastback attachment for track weekends that bolts between the rear window and ducktail mounting holes.
Also the CCP fastback is like $3,400 shipped so that made the decision a lot easier.


Happy customers. These two brothers just picked up this 202k-mile NC2 to turn into a little canyon carver. They liked @redursidae 's Caffinated Cat Motorsports stickers on the side so I included them as part of the deal lol.

Simultaneously, another mod actually kinda fell into my lap. MT member, @piripi put an Innovate wideband controller on the classifieds here for a smokin' deal, and I scooped that up. A few factors made this really enticing. I still had a stack of working widebands from my NA, my current exhaust setup has an extra unused O2 bung after the header collector, and I've heard interjections from a couple sources that the OEM NC O2 sensor reads richer than actual at lower AFR's (right where you don't want it to). The controller arrived quickly as it came from only an hour and a half away and I finished installing it the night before heading to the go kart track.


I should replace that "temporary" 10mm exhaust nut/bolt that I installed seven months ago.

Standalone wideband mounted in the header, factory upstream O2 sensor behind it that was already relocated to the midpipe. Eventually I'll ditch the factory sensor, route the Innovate output into the ECU, and make the necessary calibration changes via ECUtek to run that only. For now it's just a standalone gauge on my dash.

Calibrated the sensor in fresh air after the install and got it up and running. As suggested by some tuners, the OEM sensor does seem to read a couple points richer than the wideband controller at WOT/lower AFR's. I'm not datalogging with the gauge. I can only tell because my datalogs show 12.7-12.8 across the rev range at WOT but the gauge almost never dips below 13.0. Both sensors seem to read exactly the same ant stoich. Obviously grounding and other factors are involved, and my factory sensor may very well be 173k miles old like chassis itself. At the end of the day, I'm really just happy to have AFR displayed all the time without needing to open the OBDII reader app on the center display.



I got this far into the install before thinking to take the steering wheel off.

Hit a 5:30am wake up call canyon run with a few buddies this morning, then grabbed those stage 1 cams from my buddy. No top in the summer is kinda sick. It's almost like these cars came as convertibles for a reason.



Honestly my next mod should probably be a non-pitted/cracked windshield.



I also haven't washed the car since Buttonwillow, but that kinda just adds to the ethos.

I'm gonna try to finish swapping the rest of the Mazdaspeed valve springs and the Fab9 cams into the backup motor tomorrow. If I'm lucky, I'll only need to swap out a few of the valve lash buckets and we'll have them in stock at work. I've also got an aluminum valve cover coming in for the engine and the final few one time use parts needed to get it running. Once the backup engine is done, I'm gonna throw it in the car to break in the new cams and make sure it runs well.

 

Saw this video and thought that you might enjoy this

 

If you're still thinking about Utah, wait til afterwards to replace the windshield. Probably less of an issue in TT than w2w, but Utah is famous for throwing up rocks and cracking them.

--Ian

 

Thoroughly enjoyed that, thanks man. All these posts about 8HP transmission swaps are making me want to make a bad decision a couple years down the road lol. That car is rad.

It’ll definitely be after if I go. Thanks for the heads up, though. That reminds me, I still gotta get some mesh for my air dam so I don’t lose another radiator.

 

FWIW, I got my CCP fastback delivered about 2 weeks ago. I've been working on getting it put on the car. I had a similar experience with CCP trying to find out if any rollbars would fit.

I had a local guy look at it last week to give me an estimate on custom building a 4pt roll bar for me. Haven't gotten that estimate yet, but I'm fairly sure after talking with him, that it's going to be a fair bit more than I was hoping/thinking it would be.

I'll write up more about the whole experience at some point for anyone that's curious about the fastback.

 

Good to know, man. That's a bummer about the unexpected probable cost. I would be very interested in reading about the rest of your experience if you write it up. Sounds like your car doesn't have a roll bar as of current, correct?

 

Good work Zak! I hadn't seen the gokart track videos, that was a fun watch. I've been quiet on your thread as of late but know I'm closely watching the tuning journey with high hopes that you keep it NA and maybe grab some BBR or Caterham roller-barrel ITBs . Very good to know about the NC OEM sensor reading richer.

I'm glad those dudes like the cat sticker!

 

just the factory booger welded one.

 

I will add, that I saw the CCP NC fastback in person recently and it looks fantastic. Better fitment than the NA/NB ones I've seen, actually. I wonder if that's because the mold is brand new and the production volume on those is smaller.

 

I too was a big fan of the CCP in person. @Fireindc Do you remember if that car has a Blackbird rollbar? I know it has a rollbar in there, but can't tell from the pictures.