STR MX-5, Part II

When we’d last left off,, the car was starting to take shape. With the suspension done, and the start of the power build, it was time to move on to the remainder of the updates.
This started with a Saturday of fun. First, removing the “noise tube”, which appears to exist only to add weight and make shock adjustment in the front a hassle. Took about ten minutes and $25 in parts. Easy.
Next, I moved on to the JDL auto design header. Very well-made, easy install (simply remove the passenger side motor mount, remove all the header nuts and the O2 sensor, and reinstall). Fitment was great, and looks pretty neat too.
The next bit, I feel less great about. The Goodwin Racing midpipe was pretty expensive for what it is, so I expected the same kind of quality I was getting from the HKS exhaust and the JDL header. I was wrong. The welds look like they were done by a drunk sweat shop worker, and the fitment is VERY poor. Lots of prying and moving stuff around to get it to fit without contacting the floorboard. If I had it to do over again, I’d pursue a different option. As it stands, its done, and there was quite the fun removing the old O2 sensor from the OEM midpipe.
Finally, I took care of the differential bushing inserts. Dropped the subframe a bit, disconnecting the diff mounting bolts from it first. Slipped in, reinstalled. Easy. Should be a little peace of mind not worrying about breaking one, along with an axle, as has happened to other STR competitors.
In and amongst all the other work, I got some 245/40/17 BFG Rival S 1.5s mounted on 949Racing 6ULs.
So, the car existed in this trim for about a week, until finally taking the car up to Karcepts for some fender rolling, tack welding the slip joint on the midpipe, and corner balancing the car.
I left there, headed to an alignment shop, where I basically just took Brian Karwan’s word for where I wanted to start, and got that done.
All that’s left is the tune, which I’ve got sitting in my inbox now, just awaiting some free time to get it onto the car, which is still being driven every day. All that’s left now is to get a mic setup working, flash the tune, and probably find a way to better attach the side skirts. Karcepts also makes a small endlink, used to replace the OEM headlight alignment rod in the rear of the car, which is neat, as it fixes headlight alignment with the lowered geometry.

The STR Build Begins

After weeks of amassing parts, the STR build finally got started this past weekend.

It began with just an HKS Legamax Sports muffler. Easy install, as there aren’t many hard parts, just the two gasket bolts, and *four* hangers (only 3 are reused).

In its current iteration, its quite quiet, but I imagine it’ll get quite a bit louder once the header and midpipe are installed.

Next, the Karcepts rear sway bar. With plans to get the shocks on, I set the endlinks to the recommended length for the ride height I *would* be running here in an hour or so, and bolted it up. Very easy install. Some tight clearances, but none seem to be an issue at all. Great part.

Now, the hard stuff begins. Installing the offset upper control arm bushings up front was quite the undertaking, requiring disassembly of most of the front end of the car, and we were cutting out the front sway bar anyways to ease assembly.

Most of the difficulty was in the removal of the existing metal flange material, but the bushings went in easily, some clearancing done to the control arm to ensure no bind, and torqued down.

While the bushing install was going on, I bolted in the MCS dampers. This is probably the easiest shock install I’ve ever done. The hardest part was just one small hose clamp for the intake sound generator (I think this can be removed?), and the rear trunk linings. Also bolted the control arms back up at this point.

Finally, finished the install (which had been in progress all along) of the Karcepts front sway bar. The initial removal required a cutting disk, and some time, but install was just as easy as the rear.

The last step simply involved mounting up some Continental DWS 225/45/17 tires for all-season use, on some TRM 17×8 wheels. This’ll look a LOT better than the stock wheels for daily use.

All that’s really left now are some easier tasks; rear diff bushing inserts, the header and midpipe install, along with fender rolling and tuning. Hoping to knock this out in the next couple weeks or so.



2017 Mazda MX-5: A Return To STR

I suppose this began back during Spring Nationals, where my girlfriend decided it was a good idea to fly and drive, and codrive one of our friend’s ND MX5 in C Street. After running her HS Civic all year, she pretty quickly came back after a couple runs, and told me she was buying an ND. Great.

Now, I didn’t really know how this would affect me much, I didn’t have much interest in running a CS car, wasn’t a particular fan of the ND in that trim (or in general….), and I’d planned on keeping my C5 Z06 for the foreseeable future. Well, things change. I got offered much more for my Corvette than I’d expected when just posting a feeler for it, so it was removing itself as an option for 2018. I had a few options. First, was to go and buy a C6 Z06, the car I should have bought to begin with. I decided it was pretty foolish to go and keep spending money on ANOTHER new autocross car. So then, I was waffling between my BMW, and the ND in CS. I didn’t want to devote another season to chasing down BMW issues, at the expense of driver improvement and a desire to only lose based on *my* performance as a driver. I didn’t want to run the ND in CS, although that was looking like the option. I didn’t really want to go through the ordeal of ST prepping a car either. But, here we are…

During my 18 hour haul back from Lincoln, I decided I’d simply deal with the extra work and time to get this car prepped for STR, as they seem like a tremendous amount of fun to drive (although I’m keeping my expectations tempered in a post-Corvette world), and Brian Karwan at Karcepts, the shop who’s been building and doing most of the development work for parts and setup on these cars, is both a good friend, and local to me, having supported a lot of work on my last STR build. So, I decided to reach out to him about parts selection…

She went and finally picked up her 2017 MX5 Club in October. I’ve already got the Karcepts-Spec MCS suspension in my possession, supported by some Hyperco springs and helpers, and Karcepts spherical mounts. The remainder of the STR parts are on the way, and I’m looking to wrap up the car by the end of January, at least in a baseline trim.