Miata Turbo Forum - Boost cars, acquire cats.

- Meet and Greet (https://www.miataturbo.net/meet-greet-40/)

- - Friendly Introduction. (https://www.miataturbo.net/meet-greet-40/friendly-introduction-87297/)

Friendly Introduction.

Hey everyone, My name is Hunter and I joined some time back in 2014 but ran into quite a bit of projects that took up my time. I have been reading throughout the forums during my ownership of my Miata(s) (now on my 2nd one since joining).

It's my first instinct to join a forum whenever I buy a car, whether it be Nissans or my experience in the Mazdaspeed Forums (some of you understand what a dark place that can be, and might even know me from the South Texas NATOR meets that happen, if not...no harm no foul)

Anyways, I joined this group a day after I purchased a 1990 Miata on Christmas of 2014. June of 2015 I was involved in a wreck with a Tacoma driving idiot on his cellphone and had my dreams of a Turbo Miata crushed. Up to that point, the car had the Mishimoto radiator, thermostat, a big brake kit with drilled and slotted rotors, and an aftermarket stereo. I also had a bigger battery installed with a battery box a friend welded up for me. A 2nd motor was purchased in College Station for 300 bucks (long block, complete engine). While in the process of deciding what parts to buy for the 1.8 engine I bought, the car was totaled as mentioned before. Because of that my presence on the forums has been nonexistent.

Luckily, the insurance companies gave me a few thousand dollars for the wreck and the trouble caused by the idiot texting and driving. I landed myself into a '04 Mazdaspeed Miata in June of 2015. I was absolutely in love with the car as soon as I saw the ad. Paid the guy before I even had to test drive it because I knew I wanted the car no matter what the issues might be. Luckily enough the impulse was met with good experiences and the only real problem I had with the car is typical Miata overheating issues that eventually led to this sitting in my driveway. The engine succumbed to a cracked oil line feeding from the turbo, which was an unfortunate event that could've been taken care of it my mechanical knowledge matched my suspicions the motor was damaged. When the crack in the oil line happened, I immediately pulled over and left the car in a parking lot to grab oil. Drove it to a nearby mechanic that my engine builder recommended and he fixed her right up.

However that incident did significant damage to my rod bearings that I definitely noticed through chattering sounds that I dismissed as heat shields and/or exhaust rattles. Drove the car for about a month and finally the #4 rod bearing took a massive dump and sent the engine temps to unmeasurable numbers and the car left me on the side of the road near Austin. This mishap occurred first in October of 2015, and the complete failure happened November 12th.

So, as of today I've just ordered everything I need for a complete valvetrain job. Pistons, rods, and the spare 1.8 block that was supposed go into the NA has been completely honed and the decked about 3 weeks ago. I have the Megasquirt Pro ready to be wired (still completely fresh in the box, untouched). I'm waiting on a usable crankshaft as the one in the MSM blued and has rod bearing pieces stuck to the bands. The crank from the 1.8 I bought is forged, but unfortunately the channel where the key would mate up is damaged as well. So once the valves and springs, crankshaft, and oil pump make their way to the shop that's helping me build the engine... my baby will be up and running soon.

Thanks for bearing with my super long intro post. I figure I would cover every base I could and will happily send pics of both cars (even the wreck!) for any that are interested. They're just saved to cloud services at the moment. Thanks for any suggestions you guys have in advance, I look forward to becoming a regular around here now that I've gotten passed the stress of losing two Miatas after 6 months of owning each hahaha.

Moar pictures! It's a shame about both cars, I'm glad this doesn't seem to be discouraging you from owning a miata. I see a lot of people leaving after incidents like this. I like your style so you should keep it up.

Welcome to the forum.

We have a lot in commmon :makeout:

My #4 bearing also bit the dust, just finished my rebuild.

Looks like you have a 9.5cr supertech piston?

Welcome, hraday93. Check out the Miata Gallery and post up some pics!

Why are you using 9.5:1 pistons with a turbocharger? I'd ask if your machinist has any experience with Miata engines, but I already know the answer to that. (that bluing is 100% normal and nobody with Miata experience sells a turbo customer a 9.5:1 piston)

BTW, Miatas do not have "typical overheating issues".

hmm. interesting to hear that. Mazda told me the MSM uses 9.5:1 pistons so that's what I bought to replace the ones in the car. I had quite a bit of trouble finding those answers on my own, so when Mazda told me to use those I figured I had found my answer. As for the overheating, both of my Miatas suffered from that and coolant reroutes solved the problem for the first Miata I owned. The MSM got hot many times, even after having Mazda replace a head gasket. Coolant re-route helped a little bit, but ultimately the turbo and manifold setup produced quite a bit of heat and whenever I go to a top mounted turbo setup I hope the cooling will improve. Along with better airflow through the engine bay once I figure out a productive means of venting all that air.

I too went with 9.5 but mostly due to BEGi's suggestion and current tuning setup. My car is now rebuilt, runs great but I don't expect to be running crazy amounts of boost anytime soon. 12-14psi at the most, maybe more with E85 later.

Where in TX do you live? I'm originally from the Corpus area.

9.5:1 on 93 does not work.
E85 on the other hand is another story.

I'm in San Antonio, @Girz0r

And while I'm a newbie to this whole boosted car thing, the person helping me rebuild this motor is not. And has been building turbo motors since his dad would let him touch anything in the shop. Perhaps it's just a bunch of opinions colliding together but I find it very hard to believe that 9.5:1 is a bad choice when the people who made the car, and all of the records for parts on the Mazdaspeed list the compression ratio as 9.5:1 as opposed to the other 1.8 cars.

Like I said, I'm new to this. But my car very much idled, ran, and made boost as a stock car without issues. I never checked the stock compression to confirm the information given to me, but this is the first I've heard of those pistons not working. I also spoke to Stephanie at BEGi (in person) for a few hours regarding the direction of my build.

That being said, I want all the insight I can have to avoid having her end up on the side of the road again!

Stephanie should be the last person you ask for technical advice.
Also, the MSM kinda sucks.

I played hell with getting my engine working well with that CR, until I went to E85.

I believe the head on the MSM is different. As for the sucking part, the only complaints I've heard about it are the timing retardation and the horrible gearing. Up until this point, it hasn't been a problem since I haven't done any dig races with anyone. It had decent power for the few months I was driving it. The person before me installed a bigger intercooler and a better flowing intake as well as the Koyorad radiator. I personally love this car although I loved the 1990 that I had prior.