Scrappy Jack

iTrader: (2)

Assume Marty McFly and Doc stopped by your place with a flux-capacitor equipped, stainless steel, four-wheeled time machine and gave you the option to go back to the beginning stages of your track-oriented Miata build and give yourself advice.

I'm specifically thinking of guys like Savington, Hustler, bbundy, thesnowboarder, Orion4096, et al that are running under SM lap records at the tracks they run.

For a car that was going to get driven to an event a few hours away towing a tire trailer, what would the major components consist of (assuming an NA chassis)? Priorities are, in this order: reliability, speed, cost.


I have read:

• The Turbo Reliability Thread
• The Epic Nuts/Studs Loosening Thread - I accidentally the whole thing
• Hustler's List of Regrets Thread

ZX-Tex

iTrader: (15)

Though this is totally against the vein of this site, I would add some requisite threads from here or elsewhere on racing a V8 swap Miata. It is an option worth considering.

hustler

iTrader: (6)

Copy my car, I'd do it all over again with the lessons I've learned to get the car in it's current state: V-band, inconel safetywire, heat shielding, new rubber and joints on the suspension, check the electrical harness and clean-up whatever you need. I'd like to emphasize the need for fresh suspension parts.

I spent tons of cash on making power (twice) and suspension, now I'm dealing with problems associated with 20-year oil joints in my car. I decided to freshen all joints with new rubber from the dealer or poly from 949 and new, expensive grease on the items I've refurbed and replaced. Going through the suspension is a life/safety recommendation.

hustler

iTrader: (6)

BTW, rolling in with the tire trailer, crushing, then pulling the trailer home is awesome. The experience of driving my car around the state and crushing at the track is pretty romantic.

rharris19

iTrader: (41)

Stay N/A. Especially if you are a first time track driver. You will learn so much more and then you can move up from there. Expect to spend $6-7K at least on a built motor and all your turbo parts if done correctly.

turotufas

iTrader: (7)

If you get hit don't worry about the body shop. Just get another shell and swap everything over. If you don't you'll regret it. Ask me how I know...

Scrappy Jack

iTrader: (2)

I have given it considerable thought and it was my original preference over turbocharging the BP. However, after more research and acknowledging my lack of mad fab skillz, yo, I decided it was probably not going to be cost effective.

Also, some guys enjoy the build aspect of project cars. Given the choice (and budget), I would rather drive and never turn another wrench.

How mission-critical would you consider the built engine, understanding that you give up some safety margin per power level and (in the case of higher static compression and/or higher displacement) some powerband improvements? In other words, all else being equal, would you think a conservatively tuned stock engine making less power could fit the bill?

Anything specific? I'm assuming you are referring to all of the bushings, primarily. ARBs, endlinks, adjustable coilovers, etc are already (relatively) new.

I consider myself a relative novice, but I'm not new to handling events. While I don't have a ton of seat time between now and then, I attended my first ProSolo National Tour event circa 1999 and have been on a couple of tracks in a couple of different vehicles.

That said, I do plan on continuing to get seat time with the car in its non-turbo state while I add the rest of the supporting platform. Next up is more safety equipment and then datalogging gear.

hustler

iTrader: (6)

This is also my goal, I like driving
I think you're fine on a stock motor but I'd stay well-under 250whp on a dynojet. I look at guys like Bob Bundy who's run lots more power without incident. I built the motor because I wanted to be sure I made it home and didn't have to pull the engine again.
Upper and lower ball joints, tie rod ends, inner tie rods, and a anything that looks sketchy that holds the wheels on the car.
I had a ton of track time in my car before the build. After the build it took me a year to learn to drive this car and there is much more to go. Do yourself a favor and budget for a set of Xidas before you budget for something related to power. The sum of a 250whp Miata and good suspension is greater than that of it's parts. I can't stress this enough.

rharris19

iTrader: (41)

Had the club sports been out when I was looking at suspension, that is the route I would have gone. I would also look at the rotrex supercharger system as an option.

Scrappy Jack

iTrader: (2)

Those are definitely on my radar. I went with a non-adjustable (so I couldn't mess it up) matched setup as an interim solution while I knocked the rust off my driving skills knowing I would replace it.


Thanks for bringing that up. After wandering from link to link and bouncing from M.net back here, I came across this gem.

ZX-Tex

iTrader: (15)

I have not driven a centrifugal supercharged Miata, but I am really enjoying the Vortech installed on my M3.

scottyd

I wouldn't


That's old. Issues have been fixed for sure. Sav's car is so reliable now that I've seen him wander out to the garage and break **** on purpose just to have something to do.

jacob300zx

I would have the 949racing rental car. Xida shocks, 9" 6UL's, 245 stickies, JDM VVT, light aero small splitter, spats, diffuser, tire trailer, go pro, traqmate

rharris19

iTrader: (41)

Explain

spoolin2bars

iTrader: (1)

He asked what would you have done differently on your car.
I wouldn't have done anything different. I bought a turbocharged car with a built motor and after all the suspension, brake, and tire wheel upgrades, have about 7k into it. (Includes buying the car!) Best you can do is allow someone else to spends thousands on the car. Then when he starts a familyy and realizes that he needs to sell it, you swoop in and steal it, spend minimal dollars to finish it or do a track suspension on it and win. I already did the whole build deal on another car, and after $20k its sitting in my garage untouched since I bought the Miata. Even though I have pauter rods and wiseco pistons, they aren't necessary since I never run more than 10 psi (215whp) and still haven't maxed it out at that power level. I too know what it feels like to drive to the track, pwn on Porsche's, vette's, etc... then drive home. Although half the time, I had three tires stacked where the passenger seat used to be and one in the trunk with a bungee cord holding it down. I skipped the tire trailer and jumped to a tow vehicle with a dolly a few months ago.

JayL

iTrader: (12)

If I had never built a fast Miata, I never would have realized that I wanted a slow one.

Savington

iTrader: (31)

I regret very little about my build as it sits today, and even over the course of the build I don't have a lot of regrets.

-Spend time with the car N/A. Do all of your safety upgrades, suspension, wheels, tires, etc. with a stock motor. Learn to drive. A competent driver on 225/45 NT-01s should be within a second of the SM record at virtually any track in the country - if you're still 5-6 seconds off a turbo isn't going to help you go any faster. It is just as much fun (IMO) to go fast in a slow car as it is going fast in a fast car - I jump between my 350whp car and the 120whp rental at the track all the time, and I love driving both for different reasons.

-Once you are ready for power, it's advisable to spend a lot of money very quickly - it's always more expensive to do things slowly/twice. If you expect to track the car hard at 230whp+, build the motor - they aren't expensive motors to build and you don't need to go hog wild with crank work or head work, but get a good set of rods and forged pistons into the short block before you're stuck at the track (or on the way to the track) with a ventilated 3-cylinder waiting for AAA. You can always make a powerful car less powerful, either with intake restrictors or pulleys or softer wastegate springs, but don't piece together your own turbo setup and then replace every component piece by piece as it fails, as several of us here have done. Even if you do the labor yourself, expect a 250/300whp-capable track build to come with a ~$10k price tag.

-Be reasonable with your power expectations. A 200whp Miata will outrun a Subaru STI in a straight line. A 250whp Miata will outrun a C6 Corvette in a straight line. A 350whp Miata will drag away from turbocharged Porsches and get from a dead stop to 150mph in ~30 seconds. You're also going to be stuffing that power through a 225mm-wide tire, unless you defecate gold bullion and can afford to keep the car shod with 275mm-wide Hoosier autocross tires.

Scrappy Jack

iTrader: (2)

I guess I am asking less about regrets and "how would you build it today, knowing what you do now?"

Roger that.

10-4. That's why I listed my priorities as "reliability, speed, cost." I am prepared to spend more up front and give up some ultimate speed in order to maintain reliability. I understand that one of the risks associated with a "cheap, DIY" setup built for street pulls is the opportunity cost of missing a weekend of track time because of a preventable failure in the first session.

I am pretty disciplined with my power expectations. I am very confident that I could be perfectly content with a sub-250whp car, especially if the difference between 200 and 250 reliable whp meant pulling, "building," and reinstalling the engine.

See my next post.

Scrappy Jack

iTrader: (2)

Assuming:

• a willingness to spend money to "do it right the first time"
• an understanding that what is reliable for street pulls at .4 gees is not the same as reliable at 1+ gees on NT01s
• a willingness to sacrifice power in order to not have to build the engine
• a preference to drive the car to and from track days

What specific components should I be looking at? Complete v-band ABSURDFlow manifold and downpipe set up with a TiAl v-band GT25 turbine housing?

Or have the inconel stud kits + inconel safety wire proven durable enough that something like an ARFab manifold and downpipe with a standard turbine housing should prove reliable for the goals outlined in this thread?

GT2560R with .64 A/R turbine?

Can a low mileage 5-speed in good condition reliably handle the 200 - 225 whp power levels being discussed?

Faeflora

iTrader: (2)

I can answer the 5 speed question:

No, it can't, it will break. 6 speed is recommended and if you can get your hands on one, the mazdaspeed 6 speed shifts much more nicely and supposedly has stronger gears.