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So pulled the trigger on this. I'm working with Geaux Moto on the build. This is replacing a Porsche GT4RS. I'm hoping for similar or better lap times at a significant lower running cost. We're targeting 2350lbs. Most of this they already have running on their shop car for 3 seasons now, so this should be relatively reliable as it's their 3rd or 4th build. I waffled between an LS NC, waiting for the K24 in the ND and this. In the end I wanted something lighter than the LS build, and to keep with the 4 cylinder theme of the Miata. I suspect the LS motor NC would be faster, but this should be plenty fast.
Basics of the build
2.3 Forged closed deck Ecoboost (Built by Mountune)
G30-770 Turbo
Upgraded hpfp injectors
Karcepts swaybars
Karcepts / MCS 2WNR shocks
OS Giken
Custom Verus / Geaux Moto high downforce aero
285/30/17 Vitour P1 on 17x10
DG Hardtop
AP Front Brakes, Wilwood rears
Starting with 4PT rollbar, probably will cage it at some point
AIm 7" dash
Paint is going to be Dodge Ram Hydro blue pearl
Last edited by tblackey; Oct 16, 2025 at 12:33 PM.
Mountune builds and sells closed deck 2.3 Ecoboost blocks? That's kick ***. I thought everyone going for big power on an EB just had to go 2.0 and that the 2.3's were thrown to the wayside because of the open deck.
The fact that the MT82 can be used is kick *** too. Armand Hindrichs in TX installed an MT82 in his turbo NC but it took an incredible amount of modification to do so.
I have a 2.3 Ecoboost in a Datsun pickup. Mine is stock and automatic, but I am interested in seeing where you go with this.
I was considering upping the fuel injectors and running E85. Sounds like it may be more work than I am willing to commit to. But 400 hp would be so much fun.
Oooof, that’s gonna be a gorgeous color. I’m on board with the vent too, or multiple vents? I’m sure you’ll benefit from some side vents closer to the turbo too.
I like the vent look too, though that seibon hood does look super functional and might be the ticket if you already have it. I bet it would look a lot better color matched.
As for flares or not, I almost always vote NOT unless the wheel/tire package you intend to run is limited - in which case flare away baby!!!
So the tires are in the picture. They definitely poke a bit, but not sure flares are needed. I’d rather not, but I want to run the wider tires at it’s worth 1.5 sec
Well it looks sick as is and those tires fit better than 245s on my non flared na. But if you wanna go bigger flares it is. Looks wise I vote no flares all day long, that thing is hawt
Man, the non Abarth 124s are pretty cheap these days. They might be a better option than an ND for this kit, since the chassis is the same, but the front has an upper grille for feeding the radiator and the lower opening is already set up for an intercooler. I did check out GeauxMotos website and it appears they have a blackbox to talk with the Mazda stuff to keep the stock ABS and all that, so that wouldn't work with the Fiat. Just making a race car with their stuff should work fine, though.
Big progress, we have paint! Waiting on the bottom end from Montune to start the mechanical build. We can start the suspension though (SPL links, MCS, AP racing brakes, OS Giken, etc...)
450HP ND Ecoboom Build
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