Clockwork -> Rotrex -> Turbo -> k24z3
 

My build “Clockwork” is a 2000 NB1 in Evolution Orange. I really lucked out when I bought the car in 2019. A friend of mine who at the time worked at the body shop of a dealership called me one evening after work and told me that they had gotten a clean Miata in stock and I should go check it out as I had been considering buying a Miata for a while. My wife and I went over and looked at the car first thing the following morning. It only had 58k miles on it. It was completely stock, 100% clean, absolutely no rust. After a test drive, I made a lowball offer and they accepted. They delivered the car to me later that day and I became the proud owner of the cleanest NB I’ve ever seen in person.

I bought the Miata as they were the “ideal” autocross car. I had started participating in SCCA (Sports Car Club of America) autocross in 2015. I run with Great River Region, and am on the board. I had a ‘15 Dodge Challenger Scat Pack. That car, “Lydia”, was a beast. Holy crap did she sound good, and oh my… the torque. She dynoed 411 wheel horsepower and 405 ft lbs of torque. It was a burnout machine, and it was extremely heavy. During autocross this was a major issue. They are great cars for going in a straight line, but when it comes to turning, they are all understeer, pushing their way out of any corner you try to push it into. I had put a set of strut tower braces in the Challenger, and had a set of adjustable front control arms, and a rear sway bar which I had intended on using in an attempt to rid the car of some of the understeer that it had. Ultimately because of its poor handling the Challenger taught me little about car control, with the exception of throttle control, and held back my growth as a driver. I really did not start learning how to drive until the 2019 season when I started driving Clockwork at events.

After buying Clockwork I immediately started modding the car. I very quickly learned that modding a Miata is not only far easier than working on the Challenger, but literally everything is half the cost, or less.

After wheels, tires, sway bars and coil overs I really did not even drive the Challenger anymore. The Miata was so much more fun to drive. I ended up selling the car at the optimal time. I got an excellent price for the car. For less money than it cost me to own the Challenger I was able to build a very nice shop in my garage with a lift, and completely transform Clockwork into a street legal, 300+ wheel horsepower high revving track missile that weighs 2350 lbs with me in it and wet. Where the Challenger was a far too expensive asset to take on track, a Miata is built for it, and is at home on the track.

My build with Clockwork started with a focus on everything other than power. Suspension, chassis stiffening, brakes all were done prior to adding any power to the car. The power strategy for the car is track focused, but also very nice for autocross. I wanted a very predictable linear power curve, with simplicity and reliability. After significant research the ideal solution bubbled to the surface. The original forced induction solution was a Rotrex supercharger kit from Track Dog Racing. The C30-94 Rotrex blower provided about 14lbs of boost at max RPM. To maximize horsepower, and to increase top speed in 2nd gear for autox, the motor was fully built and revs 1000 RPM over the stock motor with the rev limit currently set to 8200 RPMs. After having one Rotrex bearing set go bad, and another completely seized up on me I decided it was time to go turbo. I used a kraken exhaust and a Garret gt2871r turbo. I had it set up to run at 10lbs on low boost and 20lbs on high boost. Here is a youtube video of us converting to the turbo:


Keegan Engineering built me a motor from top to bottom. The head is CNC ported with a fully upgraded valve train, big dual springs, larger inconel exhaust valves, upgraded valve guides, seals and lifters and custom cams. The bottom end is CP Carillo pistons and rods, with a lightened crank and flywheel. The result was a very revvy and very powerful screamer that in a lot of ways reminds me of a large sport bike motor. To support the motor the car has a custom fuel system with a Walbro fuel pump, AN fuel lines, Radium filter, a fuel rail from Flyin Miata and 725cc Flow Force injectors. Megasquirt provides engine management.

The motor was way over built for what I was throwing at it. The pistons and rods are rated to handle something in the neighborhood of 200 HP per cylinder, but I was close to maximum rated RPMs for the rods. I specifically set up the motor to run on pump gas as well (lower compression 9.2:1). E85 will not only complicate everything in the fuel system, but also push the car into power ranges that will just explode stock Miata transmissions. I’ve already gone through one transmission. I expect the k-swap will make it worse.

So, why k-swap? The built motor that is still currently in the car has spun another bearing or something. I’ve really had 0 luck with this engine. I’ve spun a bearing and warped a head, both my fault. At a recent Track Night in America the motor spun another bearing or something. Not sure what is up. The car came off the trailer fine. A week later we went to do the post-track day checks and when we started the car Rodney was knocking, and loudly. We are going to pull the motor tomorrow to find out for sure what is going on.

The k-swap plan is to use the k-power kit for the k24z3. Link g4x. I am going to take the turbo to the car.

Here is what the car looked like when I got it, this picture sucks, I'm sorry!
https://cimg5.ibsrv.net/gimg/www.mia...5b2aed77c5.jpg

Here is what the car looked like on track last track night!
https://cimg4.ibsrv.net/gimg/www.mia...7f0929efb0.jpg

Here is a relatively recent picture of the engine bay:
https://cimg8.ibsrv.net/gimg/www.mia...aa28f0f8f8.jpg

The rear before the turbo:
https://cimg0.ibsrv.net/gimg/www.mia...0e2b453c92.jpg


If you are interested I post videos in a couple of youtube channels.

My channel is mostly from in the car at track days and autocross.
My Youtube

My buddy does videos of most of the stuff we do. Here is that channel:
James Gang Racing YouTube

We will be doing videos of the k-swap!

My next post will be pictures of the motor teardown!

We got the motor pulled out!
https://cimg8.ibsrv.net/gimg/www.mia...908cceb99f.jpg

We stripped the engine down and started separating out the stuff that is leaving the shop.
https://cimg6.ibsrv.net/gimg/www.mia...e3f68e1178.jpg

We pulled the valve cover off. Nothing looked shocking. I did not take a picture, cause nothing looked shocking. We then pulled the oil pan off and didn't notice overtly wrong. Poked and prodded at the rods and didn't see anything obvious wrong. We ran to the store to get some 12 point sockets, cause I didn't have any. Freaking Northern Tool doesn't have just a set of 12pts. So I bought a bunch of metric sockets and some licorice and we went home. It turns out the freaking head nuts and the rod bolts are freaking imperial trash sizes! So, we did what was left and started pulling the billet main caps off, first one, number 3 we found this:
https://cimg1.ibsrv.net/gimg/www.mia...8f51b98589.jpg
https://cimg2.ibsrv.net/gimg/www.mia...99fc9a3f83.jpg

We are tired. We have an autocross tomorrow, which of course I won't be driving, but I do our registration. So I have to get up early anyways. I will run to the store again tomorrow and get the proper sizes so I can pull the head off and make sure it is okay. I am sure it will be fine. The rods do not look like they took any heat, so as long as their bearings are okay they should be fine too. I also expect the pistons to be totally fine. I'll get the rest of it pulled apart tomorrow and post what I find.

I also worked a deal to sell my second Miata. We cannot find the title for it, sheesh. So once I get the money for that, I ALMOST, have enough money to complete the project.

Update tomorrow!

Pretty sure I am cursed. Yesterday was a bad day. $5k of deals fell through including discovering what's in the pictures. Big set back in the project.

So, the impression is from a pin from an extension that broke. The pin fell into the spark plug hole with a plug still in it. Not knowing this a week later I took the plugs out to see how much resistance was in the motor and turned it over a few times doing this.

Yep, that is a $4,000 Keegan CNC racing head with everything.

So.... cursed.

https://cimg0.ibsrv.net/gimg/www.mia...1992d0f6a9.jpg
https://cimg8.ibsrv.net/gimg/www.mia...e46f6ad7d0.jpg
https://cimg9.ibsrv.net/gimg/www.mia...f90e0cc6c3.jpg
https://cimg1.ibsrv.net/gimg/www.mia...f5a1b92bfa.jpg

That's horrible dude. Sorry that happened.

Bummer, big time bummer at that :eek:

Is welding an option? I welded a head after a valve broke and rattled around between the piston and roof of the combustion chamber - if you think yours is ugly I'll post my combustion chamber :rofl:. It owed me a lot of money, so it was worth the expense, sold it with full disclosure and never heard anything about problems afterwards, :dunno:.

If the valves are straight, clean up the high spots from the impressions and send it. I ran a cylinder head with throttle screw impressions in the cylinder head and pistons for years without issue.

Fixing it, or running it is likely an option. But, I'm not going to run the head since I'm going to a k24. Selling the head would have to net enough money for it to be worth it for me to package it up and ship it out. Which, those 2 numbers are going to have a hard time agreeing with each other.

The other unknown is that cylinder was wet with oil. Not sure if that happened when I was flipping the motor over or what, but its the only wet one, so that's concerning.

I'm expecting the head will become a wall ornament, and a reminder not to spend so much money on motors.

If you were local to me, I’d consider buying it. If you’re not I’m sure others would too.

Any idea on why you had 2 rotrex failed? Overspin maybe? Really unlucky turn of events that is for sure! good luck with the k24 swap!

Damn, rough start to the thread for sure. However, as others have said, I'm sure there's still a buyer out there for that thing. There's way too many other desirables in it to just be hung on a wall.

Jeeze man, what a rollercoaster already. I'd run that head for sure, I agree that you should sell it. Sure you won't get a premium for it but at least you could get some cash out of it.

it does bum me out how many bp issues you've had. Wishing you the best of luck with the k.

I've been pushing the limit the whole time with this car. Pushing the limits of my skill. Pushing the limits of the hardware I'm using. Pushing the limits of my driving, lol. I've made every mistake. I've broke things in nearly every way possible. I'm 10 years deep into this hobby, and it has the best highs, and some very brutal lows.

I will get the car back together. I am going to need to part out my other NB. I've tried selling it, but it has a salvage title due to an accident repair. And worse, the passenger front clip has started to rot. So no one wants the car. It does have a refreshed bp4w, 6 speed, and a torsion. So, selling off all of that should get me a lot closer to bringing all the budget together.