Pics of subframe crack. Other side was not nearly as bad, but it was cracked too. I fixed both sides.

It cracked on this part, which is where the LCA puts it in tension when you accelerate. Probably cracked from wheel hoping drag radials on a prepped track, and power.

 

lol wow

 

Umm, yeah, wow.

 

I wonder if anyone from Hiroshima is following this thread. I think they would be both shocked and kind of proud.

 

DAAAAAAAAAMN!

 

Got the sound deadening in the tunnels/trunk floor back in. Fixed bleed hole in boost controller for rear turbo, few other little things. Car is crazy quiet now, quieter than stock by a lot. Quieter exhaust, quieter road noise. And no more stinky exhaust with the cat hooked up. Street car life so nice.

Still working on getting the boost up, made a few pulls earlier and got it to 28, then gave it two more turns but not sure what that is yet, will find out tomorrow. SHOULD be able to go a lot higher on the boost than before I think with the smaller bleed hole in the gate. If for some reason it still maxes out at 32, I'll be putting a lot more spring in the rear gate. But I expect to be able to get a lot more than 32 out of the rear gate now. Will find out tomorrow.

 

I don't know what's worse for your drag competitors. Getting beat by a Miata, or getting beat by a car without appreciable exhaust noise. Cats!

 

or getting beat by a Miata with ebay parts

 

Last time I was there I beat 3 out of 4 drag cars. The first two both put them on the trailer and didn't race again! Both of them beat me out of the hole, and I FLEW by them on the big end.

 

What's funny is pretty much every person that looks under the hood sees the tiny turbo and thinks that's it. Probably 98% of people I told it was a compound turbo setup didn't know there was another, bigger turbo on the car even after looking at the engine bay.

 

So awesome. What a sleeper.

 

Miata, 500hp, reliable in the same sentence- That's cool.

 

And one of the next steps is to make it pass emissions just like it sits.

 

You had any offers from FM, 949, etc?......Yet

 

It's been 2 weeks. Of drag passes. That's not reliable...yet

 

lol...it blew a axle destroyed a subframe and wastegate of all things fell apart.
Very far from reliable. But here is alot of kinks to work out before any highly modified car is reliable.

 

It has 650 or so miles on it so far. Here's what's failed/changed so far.

The rear turbo oiled on shutdown by my original design. I ended up chainging the drain and adding a time delay to the scavenger pump to fix that.

Rear wastegate fell apart (3 bolts vibrated loose due to bad assembly from factory). I reassembled it and made sure those fasteners will never come out again.

Axle broke racing on a prepped track. In their defense they've seen A LOT of hell before this compound setup was built. I race this car every weekend and those axles have been in the car for a WHILE....

Subframe cracked. It was cracked before the compound setup was built, I just recently fixed it. I'm sure hard launches and wheel hop did it in.

In summary, the rear turbo oiling was my ignorance, having never designed a rear mount turbo I did not setup the drain correctly. The wastegate failure was a cheap part problem, and the axle/subframe are failures from racing the car every weekend for years. If I drove it on the street on street tires and never raced it, those would never have broken, but what's the point of building a fast car and not enjoying it?

Considering I designed/fabbed probably 100 different things on this compound turbo setup, and I've only had one failure directly related to my design/fabrication skills after 650 street miles and tracking it twice, I'm happy with that. The fact that everything else is working as designed without problems is awesome, that means I got most of it right from the beginning.

Also added a shift light and some warning lights, will try to take pics of those next time I have the laptop hooked up to the car. Also going to order a MBC for the rear turbo to help it spool better, just realized I never put a MBC on the rear gate....

 

Reliable 500hp Miata was the goal stated at the beginning of this thread. That's cool.
I've got confidence. Probably going to break some more **** before he gets it just right. Take Pat's car to the street as a DD/ fun car and I bet he's damn near there. Use it the toughest way possible like it's being used and it's already ******* amazing. And some things go from "breaking" to consumables.

 

Yeah it runs well, but I want it to be very reliable, not just fast. Reliable first, then fast. I'm working on making it pass emissions with the turbo setup right now.

 

Car now has a blow through miata MAF sensor between the intercooler and the throttle body. That sucked but it's done. Just tested and it works.

Gotta make a new EGR pipe still, and a fancy controller for fuel injectors to be controlled by stock ecu when not in boost.