muffmods

Hi Miata Turbo! Long time lurker, first time poster. My build is well on its way and I figured I share my journey, discuss some serious pain points, reflect on some of my stupidity and most importantly - have something to capture all the long nights reading, the dollars spent and everything in between. It'd be cool to see the progress of the MX5! (what we call them down here in Aus) I'll start off with when I first bought my NB8A. (note, some of my posts might be long winded, but i think that is part of the story-telling experience IMO. If you aint about that life, scroll down to the cool pics).

Throwback to 2016....I got made redundant and I was quite young at the time. There was an option for re-deployment into the organisation, but the redundancy package was a HUGE amount for a an early 20 year old. I basically took the money and ran. A few weeks later (December 12th, 2016), I was the proud owner of a silver 1999 NB8A!! It was kind of almost an impulse decision, lol. I didn't even really look at any other MX5s. This one drove fine so I bought it a few days later (probably not a good idea). In hindsight, if I was to go back with the knowledge I have now, I probably would have either been patient and looked for an NA8 or perhaps the NB8B

Short sharp points for wanting to get an MX5 are:
1) I needed another track warrior. My Mazda 6mps (US ppl call em Mazdaspeed 6s) was too boat-y around the track (stock suspension)
2) Repairs on the MPS were expensive. My rear right caliper on the MPS seized at the track - had to drive about 2-300km home with a sized caliper. It ate through a DBA t3 rotor...lol
3) It runs wayyy too hot and if the thing went ZZB (zoom zoom boom), I'd cry...It's also my more 'comfy' daily driver, so I cant have this thing blowing up haha

Enter in the MX5. Slow as ****, but actually a very fun car to drive. The track we go to is called Winton raceway and it suits the MX5 perfectly with a few long sweeping turns (high speed corners). I also have a few mates who own a few already (albeit NAs) and their guidance/peer pressure was certainly a factor.

In Aus, December is summertime and this was my first drop top car. I loveeeeed it! The car was basically stock except for the yellowspeeds it had. It's an "okay`ish" coilover. TBH, I've never owned a car with coilovers so the difference between the mx5 and the mps was night and day.

This is where the story gets funny, lol.... I will never forget these events. The boys were doing an engine transplant on a silver NA at one of their houses. I came by to hang and help. On my drive up (mind you, i'm about 1 week into ownership of the car) i'm hearing this weird ticking noise from the engine. I ask one of my more 'knowledgeable' mx5 mates...
Me: "Hey bro, what is this sound on rev?" *revs engine*
Friend 1: "Ohh, it sounds like heat shield rattle"
Me: "Oh, cool - i probably will take a look later"
Fiend 2: "Uhhhhhhh, I don't think that is heat shield rattle"
*forgot how the convo went after this*

We decided to jump in all of our cars (MX5s) - time warped to Mexico and did stupid, irresponsible things. We're at about 60km, rolling start and on the 3rd beep the foot is flat on the 1.8. As my foot is hammered down..I slowly see the taillights of the 1.6 NAs.. "wtf?!" All whilst the knocking in the engine gets louder and louder.....then......the car dies. Less than 2 weeks into ownership. I haven't even done the paperwork to transfer ownership...We leave the car on the side of the road and make our way down to a friends place to swap out his MX5 for his Dad's 4WD.

Thankfully I was able to get towed home! Given it was xmas eve, we all split after I was able to push up the car into Mum's driveway safely. That night, I asked Santa for a new block for my MX5. I must've been a naughty boy because when I woke up the next morning, there was no engine under the tree. I had family gatherings and functions to attend during Christmas day, so I just left the car in the garage.

The 26th rolls around and we start working on getting the old block out.


Here's what a rod/piston looked like once we got it open:


Heat shield rattle, huh? . Ahh well, you live and you learn. I must've bought a lemon.....Anyways, the next step was to source a new block. I was an impatient noob back then, so I opted for the easiest swap possible. a direct drop in NB8A. Looking back, I probably should have done the VVT swap. Oh wells. I also managed to take the good old 'you in your engine bay' pic:


I think this was a blessing in disguise.. the failure of the stock (probably poorly maintained) engine forced me to really learn about MX5s. And quickly too! Although, the pace of the new engine drop in was going slow given it was the holiday season and all wreckers/part stores were closed

End of Jan/early Feb, I finally found an engine (80,000km), dropped it in, started and worked! Then got her sent over for a RWC (road worthy certificate). She passed with coilovers in! Woohoo! After the RWC was issued, I then finally got the car transferred into my name. It was finally back on the road! The funny thing is, it was finally registered under my name but I had a holiday planned the following day. So I basically worked my *** off to get it back on the road, only to hop on a plain after I got it transferred. Note - the stock daisys that came with the car were not really legal, so I had to borrow some buddyclubs of a mate, lol. (these arent my rims, but they look sick!). I ended up getting RPF1s in black


First mod was to install the rollbar. This took AGES. But at this time, I really feel my mechanical prowess really growing. Lots of swearing, didn't drill straight so the chassis kinda looks like swiss cheese, snapped a few drill bits but it is all part of the learning experience. Most importantly I can say..."i did this myself" which is kind of cool feeling.


Few track days took place, the car feels good, I became a better driver by going around the Winton racetrack wayyy faster than I ever did in my MPS (which had about 3x the power of the mx5). Really enjoying the car....BUT I just wish it had more power.......

I did some basic bolt ons for the MPS and boy oh boy, it is a fun daily driver. Taking that learning experience, I wanted to apply it to the MX5. I hit a limiting factor in the MPS at about 300bhp (we use kW here in Aus, so ~250kw) and they were the rods. I never opened up the block on the MPS which I low-key regret. I wasn't going to make the same regret here with the MX5. I have a very dear friend of mine who owns a workshop and coincidentally, the turbo on his Holden Astra blew. We talked turbos and then talked engines, one thing led to another and before you know it, we're deciding to forge our engines together...lol wtf.

1st regret - didnt get a VVT engine. Guess what I did? I bought a VVT with a blown head gasket:


Must've been sitting there for a while, the rust build up was crazy...it didn't even crank lol. I got a little worried..."is this block still usable?" "what if there is too much damage on the cylinder wall?!"


The block was vetted by the engine builder, the green light was given and we started the cleaning, boring process.

2) 2nd regret - didn't forge my MPS internally...not this time! I got a mad part list (actually got delivered yesterday, at the time of writing this post =D) Here's a snippet of the parts list.


I am aiming for 350-400BHP. I have an E85 pump about 3 min drive from my house (yay), so I am sure this is a very achievable target.

You're probably thinking hmmm, 400ish BHP hey? What turbo? Let me show you:


Left is my turbo. It's an EFR6758. The MPS has a GTX28 in there. The irony of running a bigger turbo on a smaller car lol? what the.... The right turbo (friend who i am forging engine with together) is a K04/K06 hybrid rebuilt. He isn't 100% sure if he is going to run this turbo though...

The tubular manifold is ceramic coated and so is the rear housing on the turbo. I picked this up 2nd hand. Apparently only 10,000kms on this set up. The dude I bought this off was just hoarding parts but he decided not to go turbo. He bought an Evo 7 so wanted to sell off these parts he collected over time and put money into that. Here's the list of things I got off him:


Now...ya'll probably be like...what diff and what gbox? I thought about this long and hard...lol. The 5 speed and open diff is not going to last, so I sourced a 6peed and a torsen (4.1 ratio)


I think I might just be rightttt on the limit here. But I figured i'd give the 6 speed and the torsen a shot. If it breaks, i'm already mentally prepared. If it lasts, NICE. I found a 3.6 open diff, so we're currently swapping out the gearing from the open diff into the LSD to have that very desirable 3.6 gearing (unlucky for you, USA). The 6 speed has a short shifter in it and I told the previous owner to leave the aluminium diff bushings in there for race car effects, lol. Hopefully it isnt too noisy/loud/aggressive.

So here we are, the 11th of August. I've dropped off the internal engine components to the builder to have him install and balance. the ETA is that I'll get this back in 1-2 weeks.

In the meantime, we are starting to do the diff conversion and the gbox has been installed (i know, i'll have to take it out again when the new engine gets dropped in...).

Once the block is built and returned to me, I'll put the block on a stand and install the rest of the components in my garage! I'll continue to update the thread as the build progresses!

Thanks for reading,
#muffmods

raynez

iTrader: (1)

Looks fun! I used to have a Mazdaspeed3 and know what its like. The 6 is even more expensive to track. Really envious of turbo setup here but looks like its going to be a riot.

muffmods

long time no update.

Here is where I am at, I had to hack up the windage tray to clear ARP studs, that was fun.

Just awaiting the fueling parts (rail, regulator, damper) to arrive then I am ready to do the swap.

p.s can a mod move this to the build thread section? thanks in advance.