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Discussion Starter · #1 ·
I started a thread like this for my old 911 on the Pelican boards and figured it was time I do the same for the Miata. Since all of you TCLers love Miatas I figured this is the best place to put it. As a disclaimer I do not profess to be highly knowledgeable or skilled with working on cars, I do enjoy it and I have little fear of mechanical problem solving. I will do my best to document the changes I do to the Miata and the experiences I have with it. Bear with me, I am not the best written or greatest picture taker you'll find here.

Background:
In November of 2015 I had my first track experience, it was at VIR with my 2015 Chevy SS. It would be an understatement to say I got bit hard! That winter was spent thinking about how I was going to back on track the following season. All signs pointed to that beautiful little 911 I had in the garage. It was meant for racing right? After my second event I decided there was too much value in that car to drive without fear. Why not pick up a Miata? I had a '91 BRG that I threw a turbo on several years ago and absolutely loved it. With the extra power it was more than capable.

I gave the guy a call that I bought the original Miata off of, he always seemed to have a couple stashed away. To my surprise the only one he had left was his red '91 that he bought new back in '91. The car was in great shape, not 1 door ding, mechanically sound, drove great, and had some good mods done to it (we'll get into that later). The car was purchased and I was on my way!





First mods and track event:
I wanted to make some changes before we did our first event together. The suspension was of unknown mileage and was a bit soft for a track car, the radiator was showing signs of browning and becoming brittle, and most importantly I didn't fit with a helmet. This meant new coilovers, an oversized radiator, and new seats and harnesses.

For the suspension I went with the 949Racing Xida coilovers with 700/400 springs. These things are a work of art. I was nervous purchasing such a high spring rate but on the track they're perfect (if not a bit soft still). They allow you to ride up on the curbing without disrupting the balance of the car and quick transitions are controlled. Even on the 2 hour drive down and back they were exceptional. I'd highly recommend these to anyone in the market for a good track ready coilover.





Still tweaking ride height....more on that in a little.



Next up was the gigantic radiator. I ordered a dual core triple pass crossflow radiator from Trackspeed Engineering. This thing is MASSIVE. It actually took me a couple days to get in because of its dimensions. As I removed the old unit I saw a leak, decision was completely validated. Nothing really tricky here, just a radiator replacement.



And finally it was seat time. This is a tough area to figure out with the Miata. Not many seats fit between the tunnel and the doors and at 6 foot tall most mounting methods were too high. I settled on a set of Track Dog Racing Ultrashield Rally Sport seats. Track Dog modifies the normal Rally Sport seats to make getting in and out a little easier. Track Dog also offers a "super low" seat bracket that requires the removal of the rear seat mount on the Miata floor. I unfortunately didn't take pictures of this but it basically requires the drilling out of several spot welds. You then bolt the new bracket in with the stock front mounts and drill new holes for the rear. The kit comes with large washers to reinforce the rear floor portion for safety.

At the same time I installed a Hard Dog harness bar and Schroth ASM 4/6 point harnesses. The ASMs allow you to run a 4 point, one strap has some give in it so when an incident occurs it allows your body to twist like a stock 3 point does. I wouldn't consider this safe for the track really but on the street I prefer this setup over a normal 4/5/6 pt harness. These belts also come with the option of adding on a submarine strap, I added the 2 extra belts for track use.

Not many pictures of this process but here they are installed:



And all that brings me to this....

 

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Discussion Starter · #3 ·
It was our first track day together and it was a new course for me, NJMP Lightning. The day started out wet and in the mid-40's. Not exactly a day you want to be flying around a track with the windows down. As the day went on things started drying up pretty well. As I got used to the car and the track the lap times dropped. Midway through the 4th session it started misting out. Nothing too bad, maybe every 30 seconds you tapped the windshield wipers. I was flying down the front straight and hit the brakes to prepare for turn 1, a blind right with a small crest. As we went slightly weightless I kept the wheel turned which as it turns out is a BIG mistake! As the front recovered grip the rear was still light which sent the back twirling around. I slid for a bit on the grass and finally kissed the tire wall. 5 feet further and it would have been the concrete wall. I'm very thankful for the little amount of damage it did and felt completely validated that I bought the Miata and retired the 911.





After a new (used) door an a fender we were back in business.

 

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All was looking good and then I got to the last picture in the first post. :eek::(

I do want to do this sometime in the future when I have a little more time on my hands. I've done several autox events in the past and one that was borderline road course with a few cones mixed in. That's what hooked me.
 

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Discussion Starter · #5 ·
Phase 1.5
It was time for us to get back on our feet and learn some more driving skills. The first time on the track it was in the mid 40's, running temps and oil pressure were stable but as we planned more events I was getting worried about those 2 items. In the turbo Miata world there are typically two concerns; 1. will your turbo hardware fail and 2. will you overheat. To address #2 most people upgrade their radiator (done!), improve airflow with ducting, and add an oil cooler. Game on!

First up was finding an oil cooler that was within my abilities to install. Flyin' Miata carries a small 13 row Sentrab cooler that attaches to the steering rack. It is higher than the subframe so we're not worried about ground clearance so much. The difficult piece with this unit is ducting, you want to put something in front of it to scoop and force air through it otherwise it just acts a big heat sink. Here is a picture of the oil cooler installed, I do not have pictures of the ducting but imagine a driver duct mounted to the front of this.



The next step was to ensure all the air that entered the mouth of the bumper get forced through the heat exchangers. Here's what I was dealing with:





Massive clearance issues here! After messing around for weeks with how I was going to tackle this I decided it was time to ditch that Starion intercooler and AC condenser. So far the best decision of this build. I picked up a Precision 350 intercooler and got busy doing my best mounting it (remember how I said I wasn't the most skilled at this?). I basically cut apart some square stock and used the AC condenser mounting holes. Not pretty but it works well.





Now that we have simplified all the lines and exchangers up front it was time to start devising our plan. Out comes the cardboard!



I tried very heard to use metal to finish this up but it just wasn't working for me. I ended up making the panels out of a sheet of ABS plastic I bought off of Amazon. As it turns out it was a great choice. The ABS has a melting point above 300 degrees which is hotter than the radiator will ever get. It's also very easily formed using a heat gun and you can even rivet it together. I again used the old mounting points for the condenser to hold the side panels in place. For the top and bottom the radiator I have has a small lip in it. I was able to bend the edge of the ABS to catch onto the lip, the top and bottom were a perfect seal. The sides were still tough with the intercooler piping but in the end I think it turned out pretty good. That coupled with the newly installed hood vents kept temps low through the next couple track days.

Excuse the sag in this. The bumper ties into the upper and lower portions of the duct and flattens them out while also sealing the mouth





And hood vents!







And here we are back on the track!

 

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Discussion Starter · #6 ·
Why is that hood grey?
After my little off-track incident I couldn't stand that my panels didn't match. As much as this is a track car I'm a bit of a detailing snob. I couldn't stand that the door was a different shade red and the fender was black. I refused to pay money to paint this car as I am still fairly certain it will have another incident like this in its future. I was looking at vinyl wraps one day and stumbled upon a guy on YouTube named CKWraps. He goes over how he installs vinyl on different parts of the car. I decided to order some samples and try my hand at it.



I must have tried a total of 25 different colors from 3 different manufacturers. I eventually landed on Avery Dennison Gloss Dark Grey, it reminds me a lot of Nimbus grey from the mk1 TT. I was thinking matte but the squeegee left a trail on those that didn't seem to self-heal. I also found that Avery Dennison was a little thinner and the adhesive was easier to work with, both pluses for a beginner. Slowly but surely I began to cover her.



The trunk was actually surprisingly difficult. Decided to test fit a spoiler I liked.



In the midst of all this I did a few more track days. I had been complaining about the lack of grip on the Hankook RS-3s. They typically get great reviews but I think mine are past their useful track life. Everything felt squirly, I was always driving on the edge. It was time to fix all this.

I mentioned above about ride height. For a street driven Miata the recommendation is a 1/4" higher in the back than the front ride height. I followed this method in setting my ride height. What I found was for my setup this wasn't right. When I would turn in to a high speed corner I felt the back end kind of lift and slide (hard to explain). I was certain it was tire pressure but everything seemed right. I dropped the rear 2 turns on the coils and it behaved a ton different. The back felt a lot more planted.

While under there I noticed something else, a missing rear sway bar! I knew the guy I bought my car from was a big auto-xer and it is standard practice in the Miata world to remove the rear bar but I never thought to look. I found a thicker front sway and matched rear bar for the car. The front is a pain to install as it sits above the oil cooler, boost and radiator hoses. After getting that all worked out I made my way to the back. I got all that installed, went to torque down the final nut and SNAP! The stud that holds the rear sway bracket on to the subframe is no more. I tried for 4 hours to drill that stud out. A combination of fatigue, frustration and dull bits led me to remove the front bar and go back to stock. I had a track day the next day with my new R-comps and I couldn't wait!

I picked up a set of Avanti Storm S1 in 15x9 et35 and got them wrapped with 225 Nitto NT-01s. Oh. My. God. My usual track I'm on is Thunderbolt at NJMP. Spec Miata record there is around 1:35, my best time up to this point was a 1:48, and that's with 200 whp on tap. My first session out with the NT-01 netted a 1:38 best lap. I dropped an easy 10 seconds in my lap times by just switching to the R-comps.

Some fun on that day:





And my buddy in his GSR showing me the lines:



Unfortunately that day was cut short.
 

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Discussion Starter · #9 ·
And so Phase 2 begins.
The last track event I was at I had to cut a few sessions short. The first session was flawless, second session the car hiccup'd a few times after about 15 minutes and I decided to come in and check it out. The third session it barely lasted 5 laps before it had issues. I chalked it up to old spark plugs and decided it was best to limp the car home than push it on the track.

Just to show my priorities, instead of fixing those issues I just kept wrapping.









The hardtop was a b!tch and required lots of help.



It felt good to get it back into 1 color.

After playing with my fun little stickers it was time to get focused on prepping the car for VIR the first week of November. I started her up and realized that it sounded different, made my way to the engine bay and found this:



Torquing it down did absolutely nothing. It was a major exhaust leak and I am now attributing the hiccups and loss of power in the last track session to this. It made sense to me it was heat related as it would only show up mid-session. What I'm thinking was happening is the underhood temps were rising significantly due to the hot exhaust and the coil could no longer deliver good spark. I know, it sounds a bit odd but when the car was cool, even on the drive home, not one issue. I decided I could take the DP to get machined to just hold me over to the next event. In order to do that I had to remove the turbo....Ooops!



I have been defeated. The old Greddy setup was not worth trying to resurrect. I did not want to tow the ****box 8 hours to VIR so that it could let go on me in the first session. It would have been a weekend off and $1k wasted just for stubbornness. it was time to get serious.
 

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Discussion Starter · #11 ·
The decision on my direction was primarily shaped by this:



About 25 years ago my dad dragged this boat home, my mother just got her license and the family needed a second car. My father's commute was a whopping 1.5 miles each day, reliability and gas mileage wasn't really a big thing for him. Over the next 8 years we worked on it extensively. I'll never forget the day the timing chain broke on the way to the orthodontist appointment, the oval muffler ended up round with a single backfire. My brother took her to the prom, I took her to the prom, when my mother passed away working on the Olds was the only thing we could agree over. It has serious sentimental value to me. Just thinking about it brings tears to my eyes.

Anyway, after convincing my father to sell is '64 Corvette and buy a '63 Riviera he has now decided it's my turn to watch over the Olds. There is quite some work to do on that car, part of it from sitting outdoors and part of it from my father just kicking the can down the road. If I have to chose between spending time on the Miata or time on the Olds, the Olds will win. Whatever this next step brings for the Miata must be RELIABLE.

I spent some time speaking with Flyin' Miata and Track Dog Racing about what I wanted to do. Trackspeed Engineering has an amazing track proven turbo kit for the 1.8s but I really didn't want to get into sourcing a junkyard motor and doing a swap. The 1.6 is (somewhat) healthy and it made no sense to add the complexity. I did however want to be sure whatever route I went was mostly transferable to the 1.8 if the 1.6 ever let go. In the end I decided on Track Dog's "track package" Rotrex setup. I added in MegaSquirt, a 6 rib setup, smaller radiator to clear the over-rad charge pipes, and some other odds and ends. This package should be good for around 220 whp and 170 ft. lbs. of tq at the wheels, more than enough for a 2200 car. In the midst of all this I'm going to finally remove the AC compressor and ditch the power steering. I've also decided that this will be done "right", cleaning up all the little bits and archaic mods the previous owner installed (piggy back eManage, etc.).

This is how she sits as of last night. The tear down begins!





Very excited to get this project moving.
 

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Looks like you car got its first door ding. ;)

While under there I noticed something else, a missing rear sway bar! I knew the guy I bought my car from was a big auto-xer and it is standard practice in the Miata world to remove the rear bar but I never thought to look. I found a thicker front sway and matched rear bar for the car. The front is a pain to install as it sits above the oil cooler, boost and radiator hoses. After getting that all worked out I made my way to the back. I got all that installed, went to torque down the final nut and SNAP! The stud that holds the rear sway bracket on to the subframe is no more. I tried for 4 hours to drill that stud out. A combination of fatigue, frustration and dull bits led me to remove the front bar and go back to stock. I had a track day the next day with my new R-comps and I couldn't wait!
Bolded for truth. This is the truly random element of an older car. A simple repair goes haywire when an outwardly harmless bolt snaps out of the blue. Hours go by. Every tool is called upon and offered at the altar of Fe2O3. Every bit and extractor at the local hardware shop is used, ending up either dull or broken off in the bolt. Lasers and even satanic offerings are contemplated. The pure virgin blood that is PBblaster drips into eyes and up nostrils.

It's only a simple sentence in your post, but man does a broken bolt ever suck. Peace. :beer:
 

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Discussion Starter · #19 ·
Looks like a fun project.

Just one question about those hood vents. Is that a common location? Looks like they might be far enough forward to still be in a high pressure area.
It's not the best placement for the vents but it keeps the structure of the hood and is still effective enough for my purposes. Here's a layout of the pressure on the hood:



My weekend was full of pulling parts and figuring out wiring and loose connectors. A lot has been done to this car through its life and some rework is needed. Things I've removed:

- Fuel pressure sensor for gauge in A-pillar
- Boost pressure sensor for gauge in A-pillar (gauge was always off anyway)
- Another boost pressure sensor for the zetronic gauge setup
- EGT sensor for zetronic gauge setup
- AC related wiring
- Airbag related wiring
- Charcoal canister and associated bits
- Washer bottle
- rising rate fuel pressure regulator (mostly removed)
- AC lines
- Intercooler and piping
- Ducting for radiator
- Radiator

My new kit should be in Wednesday night and includes a new intercooler, radiator, coolant reroute, belt setup, supercharger and associated hardware, and the MegaSquirt. Once I figure out how it'll all be setup some of the above might have to be brought back in (i.e. gauges, ducting)

I'm also contemplating doing a full wire tuck including moving the relays and fusebox into the cabin. Between the turbo timer, eManage and the Autotune setup there are a lot of additional wires that need to be removed. I'm planning on taking the dash out anyway and most things are disconnected, it's probably the right thing to do.

A few pics of the weekend, nothing pretty:



 

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Loving this thread :thumbup::thumbup::thumbup:
 
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