GRM article

https://grassrootsmotorsports.com/ar...a-displacement

The delta is what matters, obviously. This is our "Budget NC" build (the car pictured in Emilio's top post). Lower line original 2.0L motor with exhaust system, upper line our junkyard 2.5L, Xero Limit cams, exhaust and requisite tune. Standard 91 octane fuel, we haven't changed over to E85 yet so there's a bit more easy power to be had there. I think we may have done some additional tuning work with Xero Limit after this dyno day because driving the car I don't feel that torque dip/spike, but then again most of my time in that car is on track far above 3,000 RPM. Peak gains + 40 whp / 50 ft-lbs.

https://www.mazdatalkforum.com/downl...6230&mode=view

I will be picking up a 2012 Grand Touring (6-speed with an LSD) with 94k miles for 10k next Sunday. I intend the leave the engine alone and build everything else up first, while building a 2.5 myself on the side.

I got a PPI done on it, but otherwise I am buying blind.

I've owned my 2006 NC1 since new. It was my DD and weekend autocross car (CSP) for the whole time, including SCCA SoloNats (I was the only CSP car driven to Lincoln - it won a CSPL National title with Juliann Pokorny in 2009, and I trophied 4th in 2011 having led the class on Day 1). It's now a trailer queen SCCA Time Trials (Prepped 3) track car. Still normally aspirated (looking at my options to go further), the 2013 MZR 2.0L was rebuilt by Jesse Prather with XeroLimit cams and intake and custom 1.75"id primaries PPE LTH, running E85, pulling 190whp and 147wtq.

i think LFX is the way to go now...
for a dedicated track car id def go LFX. its light, its Normally aspirated so no heat issues and you get the engine/gearbox and ecu in one nice junkyard package.
sell off your mazda motor and 6 speed and your half way here...
LFX in an NC has got to be the best bang for buck surely?

I would tend to agree, except that I don't know of ANY LFX NC builds out there with any real info on them. Do you?

Here's an LFX NC build: https://forum.miata.net/vb/showthread.php?t=676578

Not a ton of info there, and looks like lots of teething problems with the swap parts. I was looking into this when we had our NC (for a street build), but there just wasn't a lot of info out there, and still isn't, even though there are a few running around now. It just takes time, because it's still not a common swap. I think it will become more common as the NC values continue to trend into track car territory.

On a similar note as the LFX NC, Keisler has now buttoned up a kit to swap the LFX powertrain into RX-8's.. There's a couple builds floating around where owners are in a total of ~$12.5k for car + swap parts + LFX & Getrag junkyard parts netting 300whp in 2800 lbs with full OEM interior.. Seems like a very strong value/dollar ratio on that as well.

https://v8roadsters.com/product/nc-lfx-mounting-kit/

It's been out for a couple of years. The car Shandelle wrecked that put him in the hospital was an LFX NC. The engine fits in the chassis very well and looks totally factory when done.

And can't you stuff ridiculously huge tires under the stock fenders on an RX-8?

Yea the Formula Drift guys have been stuffing insane tires under the fenders for years. Tubs + fender flares gives them room for 305+.

I've also heard that RX8 wheel tubs or custom tubs on an NC allows you to put 285+ tires all the way around.

I'm excited to see how companies continue to improve the NC. Maybe i'll pick one up some day. Would certainly fit me better than my NA.

That must be the turn-key builds, because the kits done by actual customers have had lots of problems.

I know we've done 285s on 18x10.5 with the big flares for autocross. Stock chassis, not tubbed. Brian says he's done 295s in the rear on that car.

I can't find a pic but below is 265 on that car on the same 18x10.5

https://www.mazdatalkforum.com/downl...6686&mode=view

Now THAT is an impressive swap. Great chassis, room for any size driver, cheap to buy, etc.

+1 to NCs being great cars, if I was starting from scratch I'd definitely go that route. Relatively inexpensive parts to get you to ~200rwhp and like 2300lbs or less dry. Which is good for GLTC, ST4/TT4-ST5/TT5, and an all around good HPDE setup.

We (9LR) get requests often on more development with the chassis. CFD data for the chassis, front aero, etc. The NC wáng kit also has done well since it's release.

It's great to see the "track" market on NCs grow :)

MER has built a few LFX NC's and RX-8's. They're fast. There have been some issues with spun bearings on track. The engines sit way back in the chassis yielding nice balance.

The nc is a no brainer now.. Its so much better than the na/nb.... Even for a light track car it comes with all the good bits like big brakes, easier to install a cage than na/nb. Great front end sheet metal which lends itself to proper splitter and radiator/intake ducting. Bigger wheel options. Better suspension geometry. And of course can fit other engines like rotaries or v6 without cutting much (if at all) of the chassis. Even things like the canbus mean you can ditch the stock instrument cluster and fit something like an AEM CD7 dash logger etc.
If I were to start a build it'd be an NC with LFX, CD7 Dash logger, rx8 abs pump. 17x9 wheels heavily ducted stock brakes. (we generally run sub 10 lap races in most classes)

The NC became a good double duty option the day we introduced the NC RZ roll bar.
Until then you either had to dump a bunch of money into buying the GT3 bar and a hard top or settle for a bar that is heavily compromised.
The RZ changed all of that, giving owners the option of keeping the soft top and all the interior as-is (save the usual trimming) and a HUGE hoop that fits tall folks like no other Miata with a fully SCCA legal construction.
It's probably my favorite bar that we make, engineering wise.
You're welcome! :wavey:

How many ribs did you have removed in order to do that?

You'd think that solving a major issue for most track rats is pretty cool.
But maybe not...