1990 N/a Miata Autocross and Track Build

Hey all! 

I'm a new member of this forum, but I've been reading it for around 6 months. I just recently got a new project car, a 1990 Miata 1.6. The previous owner ran it in Rallycross, but a lot of the suspension components and engine mods will be useful in track racing as well. I will share some pics and then will discuss my plans with it: 

I picked it up for $2250 without a top (the owner had a hard top on it, so I said if he dropped $1000 off the price then I would take the car with no top and just tarp it til I found another one. 

I since was able to pick a soft top up for $20, it has the rear window missing... If anyone has a window section, or knows anybody with a window section I would be very interested. 

After that I picked up a set of 15" wheels off of an e30 with Falken Azenis RT615K's that have some good life left in them for $225. The last picture you see is how it sits now, however the wheels will not be that far out. I just kept the spacers on that were designed for the original daisy 14" that came on them - I have 3 bad wheel bearings so while I'm down there I'm going to put new hubs, and bearings on all four corners. The spacers were locktited on good and I'm not one to wail on it with a hammer if I'm going to be pulling the entire thing apart within a month. 

Parts I'm planning to get soon: 

Maintainence items: Oil, Spark Plugs, Wires, wheel bearings, and hubs. 

Suspension items:

I'm looking at a set of re-valved bielstiens with 700lb fronts and 400lb rears. He's asking $500 for them, but since I have Yokana coilovers on it already I might pass on them. However it seems like an OK deal. 

I have already agreed to the purchase of pop-up assembly's and a racing beat front sway bar for $40 from a gentlemen up in NH. 

Structural:

I'll be having a friend fab up a 4 point roll bar, as well as putting in a new seat as the previous owners is not too good. It's usable but not great. 

I'll probably be adding jacking points at the pinch welds, as well as frame bracing. There are some holes towards the front of the rocker which I'll be patching as well. 

I'm currently in college and going through finals week, so I don't have much time (or money) at the moment to dedicate to the car. However as soon as my classes end (next week) I'll be trying to do a lot more. 

First order of business is stripping it down and removing anything I don't need. After that it will be making it run right (it burns a good bit of oil on cold start) and putting some performance parts on it. 

Thanks, and I'll try to post frequently 

Edit: 

I didn't have time to mention what my overall goal is with this car when I was originally writing. But I'll explain that now:

My overall goal with the car is to run autocross for the remainder of this season to help get comfortable with the car and see what I need to do in order to make it handle to its best ability. After this season is over, I'm planning to make any changes and safety modifications for it to be able to run EMRA ST8 (I believe) next season at Limerock, as well as doing a few test and tune days. 

The end goal (which is definitely subject to change) is to put an Ls3 block and 4.8 cam setup into it. That would be around 600hp at 8krpm. But that is proper rocketship territory and best suited to a time when I have more racing experience then I do now. Learn on the 1.6, maybe boost it til it rod knocks, then swap the V8 into it. Or that's my plan for now. After driving the miata as it is I'll probably abandon the idea and just build out a less powerful engine. But the idea is neat and I'd like to see it. 

Neat. Outgrow the 1.6 before you go nuts with it. Speeduino pnp for the 1.6 is an extremely cheap way to get aftermarket engine tuning for forced induction. 

I've done the thin lexan and marine glue truck for a rear window. Mine was ugly but mainly because I just needed something to keep water out until I got a hardtop. 

Little work has got done, as finals week and work has kept me pretty crammed. 

However I did get the inner fender lining and other "rub-able" jut outs and other areas removed or otherwise relocated. I need to extend and relocate some wires that normally run behind the inner fender to a different place before hard driving, but I think that I can get away with a drive or two on the road with them where they are. 

Got a better look at the spacers on the wheels - I'm not surprised three of my wheel bearings are cooked. 

Yikes. Though I'm glad it worked out like this because it forces me to do the boring but important stuff I would otherwise overlook. Nothing quite ruins a trip to the autocross like forgetting routine maintenance and needing to deal with hellish noises from your bearings the entire ride home. 

Tonight's plan is to do some more gutting work, as well as to adjust the E-brake which barely holds the car in place. 

Sunday I am picking up a racing beat sway bar, and possibly a kirkey seat. 

Fun times. 

So I got a little bit done, albeit less than I would have hoped for. But this is due to getting smacked with bills, not from lack of motivation - progress of a kind! 

I'm working on the PCV Valve setup now. Originally when the car came to me, it essentially had a piece of tubing that was kinked in the middle that ran from the pcv to the intake manifold, just as a quick fix, I ran a catch can between both ends to try and stop any excess oil burn - didn't work. I think valve stem seals are the culprit for that. 

However, with the tinkering I did, the silicone calk (yeah, you read that right) started to crack and create some vacuum issues. 

Another short term fix: 

I bought a PCV off Amazon for $6, and I used a combination of silicone and epoxy to hold it in place. I wanted to seal it so my idle would stay consistent, but I wanted to drive it a bit before I get a new valve cover which will have a threaded AN fitting going to the can then to the intake manifold. This is what I got so far:

This is the gunk filled previous attempt. But since I'm going with a new valve cover relatively soon, I'm not too worried about making it look pretty - it just needs to work. 

I used a good bit of silicone to make it get a good seal.

Then epoxy as a top layer to hold it all in. 

I will say it's not how it should be done, nor how I will do it when the motor build is finalized. However for something that will let me rip the car through some curvy roads, I'll trust this for a bit. 

The sway bar unfortunately didn't happen last weekend as the guy had something come up. Though I'm not really in a position to go splurging on a ton of stuff yet. So I'll probably end up getting the bar then go on a small hiatus from doing anything besides for driving it. 

This post will be slow going but I'll try to keep everyone updated. A lot more will happen this winter, too. Thanks for reading this far, you trooper. 

Welcome!  I have an NB1 and have only had it for almost a year.  I also know what budget limits are like.  2 questions:

What are you doing with your current seat when you replace it and what wing/spoiler thing is that on your trunk?

In reply to Justjim75 :

- I'll probably either swap the seat into the passenger side or sell it. It's only holding on by 2 bolts right now because the PO got a bit shifty in the mounting. 

-I'm not sure about the exact type of spoiler it is as it was on the car when I got it, but I'm really falling in love with it. Especially with the rear bash bar being exposed now:

Update:

So parts have started to arrive, along with more problems! I took it out for one of the first times after getting the pcv working. Here are the problems I noticed:

- the worst thing: on gear shifts it started to buck and jut even when the foot is fully off the clutch. 

-when I am fully off the gas, the car has a horrendous vibration and slapping noise from the rear of the car. I think it has something to do with the driveshaft? Or the diff is just toasted and the car will be parked for a while until I can sell the turbo kit and swipe a diff. 

- Lastly, the suspension is way too low in the front, to the point that I'm scrapping the front driver side on the ground around corners with two people in the car. 

A lot of stuff to fix, but hopefully my motivation won't fade. 

I also put a lexan sheet into the back using marine sealant as a user on here reccomended previously. Seems water tight, but not too pretty. It'll get the job done though.