1990 Miata Build by switched

8 minute(s) of a 297 minute read

Well, good news and bad news. The bad news is there is still an oil leak- I'm going to yank the engine back out as I believe it's leaking either between the block and the pan, or the block and the oil pump. The other thing that happened was I blew out the diaphragm in the vacuum booster on the last pull we did. The car technically is drivable now, so once I fix the issues I'm going to put some time on the engine before I head back to finish the tuning.

On the last pull, the car made 256whp. I took some videos, I'll post them when I get the chance.

9/7/2010


Yanked the motor over the weekend to fix the leak I had between the pan and the oil pump (that damn rubber gasket). I ran out of steam yesterday, but I am about 90% done. Hoping to get it back in working order after work today.

9/12/2010

So new problem :vash:. I recently pulled the motor to fix a leaky oil pan gasket. I got everything back together, and when I started it up, the car is idling around 2000, fluctuating sometimes up to 2800 rpm. It's pulling ~17mmHG vacuum at idle (used to be over 20). So OK, must be a vac leak somewhere. I pressurized the system up to around 10-15psi and I am getting some air flowing out of the catch can. The catch can was also about 1/2 full of oil (not sure if this is normal or not). I'm running a PCV valve from a 323 to a catch can. I was able to blow through 1 side of the PCV valve, so I believe it is functioning properly. I also tried removing it from the system entirely, which didn't fix the idle issue.

Here's an old pic of the engine bay showing how I have my catch can routed for reference:


Any ideas? The car ran fine before.

I just did another boost leak test with the valve cover off, and it seems like one or more of the valve seals is leaking. When I pulled the spark plugs out, cylinders 2 and 3 had a little bit of oily residue on them. If it's not one thing it's another..... boy do I have good luck!

9/23/2010

No miata updates yet, but I do have news to report! I just picked this up on Tuesday to replace my jeep as a daily- 09 Mazdaspeed3 GT with 30k on the clock.



9/20/2010

Got the car back, they fixed the idle issue. There was a 2mm gap around the throttle body mounting holes and the holes in the flyin miata adapter- welded them shut, redrilled them a little lower and my idle issue is back to normal, so 1 problem down.

They didn't look into the oil consumption problem, but did note that it's not good . I'm going to run a compression and leakdown test and go from there. The catch can fills up with oil really quickly. It pulls 21mm of vac at idle, and is making full boost (14psi off the wastegate). It doesn't blow smoke at all. The car has had maybe 2 tanks of fuel run through it.

11/3/2010

update:

I did a compression test after letting the engine get up to operating temp. My results were 218-218-220-220. The plugs looked normal as well. I took the oil cap off while the engine was running and there was a steady stream of air and oil dropplets coming out. I don't have a leakdown tester, but that's next on the list of things to check once I can source one.

11/14/2010

I lowered the car on Friday and took some pics. I want to lower it more, but I need to trim the inner fender lips a bit more in order to do so.









12/6/2010

I've decided to put the car away for the winter, to resolve this oil issue and start on stage 2 of my build. In preparation for that, I have been getting the garage up to spec. I hung up some shop lights, got a new stereo, a kerosene heater, and hung an original Mazda dealer banner from 1990 when the miata was first debuted!



My lovely wife recently surprised me for my birthday with a new rolling workbench/tool chest. It's frigging sweet! Took about 3 hours to assembly and fill with my tools



I have a few more additions/changes planned for the garage, but it's essentially ready for work!

12/10/2010

About 2 weeks ago I went for a last ride of the season with a friend and his 99 2.5 RS. He took some really nice photos, thought I would share:






















12/15/2010

Took this shot last night of a few of the parts waiting to go on the car:

ATI Super Damper and an Aeromotive FPR:


12/17/2010

Got the car back to it's "normal" state today . Started with pulling the dash out (had to pull the front portion of the cage out in order to do so)...


and then I removed the front bumper, and front fenders


so that I could pull the entire wiring harness through the firewall to begin my "Proper" tuck...

drivers side:


Passenger side:


I still have to go through the harness and get rid of everything I don't need, along with tidying things up a bit. My goal is to hide absolutely everything. That's all for now!

12/19/2010

Just finished delooming the harness, and I am officially airbag free- I stripped out all the wiring associated with the airbag, as well as got rid of the air bag module, the air bag capacitor/backup battery thing, and the cruise control module. I brought a few relays inside the firewall too. I still have a little tidying up left to do, but the majority of the big ticket items are taken care of. No pics as it looks like a disaster area