Yup. I remember on my old 97' outback it was a ticking time bomb.

 

miata h4

 

After looking at the intake manifold again today, i'm almost 100% sure that is where the oil was pouring in through. My worst automotive fail to date, I think.

The port on the IM that I had the valve cover port hooked up to.


The inside of the IM, oil pooled under where that port is.


Heads both look like this:



Headgaskets looked fine:


Cylinders:





The carbon on the pistons seems to flake off in big chunks, I'm guessing that is new from the suck-by (reverse of blow-by).

Thinking I'll clean the tops of the pistons, clean out the intake manifold, get some new gaskets and go back together. Learn something new everyday.

 

That's a clean engine for sure. Yeah clean up your mess and reassemble and don't mess with it anymore.

 

D.I.Y. brz/frs! I came across this a few weeks ago:



I think i'm going to wire brush the pistons, clean the mating surfaces, and slap it back together with some felpro gaskets this weekend.

I've read tons of people liking the felpro stuff, and some people who only swear by OEM. I know the felpro is the "revised" style gasket, so i'm not too concerned.

Any tips on cleaning the head/block? I'm thinking razor blades very carefully, then maybe scotch bright pads and degreaser.

 

I used a stiff putty knife for the surface, then a scotch bright with some Brake parts cleaner. It ended up looking brand new. On the spot that had lots of carbon where the gasket gave out, i gently used steel wool, but it came clean as hell

 

Yeah that will work. Be careful with the wire brush not to touch the cyl walls. I used fel pro gaskets before on a legacy, didn't have any issues.

 

Soaking with Marvel Mystery Oil should soften the black stuff on top of the pistons. Liberal grease applied with a finger between the piston and cylinder will keep the clag out of the rings while you work.

 

or just gasoline...

 

Great ideas guys. Will keep all that in mind when I make it to the garage. Got a nasty illness of some kind and I've spent the weekend recovering. Fun stuff.

 

My entire family has the plague and I'm hoping that since I spent most my time in the garage I avoided it! Little kids are the bringer of all things sickness, drives me crazy. Every time I visit my siblings I get sick it seems. Get better man!

 

Haha, the plauge. That's what this felt like, but was pretty much a 24 hour sickness. I'm doing pretty well today, hoping to get things sorted out on the scoob this week.

Stay healthy! I want constant updates in your thread

 

^ lol @24 hour sickness, I felt better for one day and got a little done on the motor.. then was sick for over a week straight. It was seriously one of the most horrible experiences. Finally starting to feel okay now but I'm not pushing it.

Made 1 side of the motor look like this:


Soon enough I'll get back up to the shop and knock this scoob out, i'd like to work on my miata soon. Starting to get the itch.

 

Dang. Almost looks like Jeff has inspired you.

 

Damn, good work!

 

Looking clean, good job.

 

Thanks guys. Just thinking about boost and looking at these forged rods and the gt2860 sitting on my desk is getting me excited for spring. Tenative plan now is to knock out this scoob, which can hopefully become the DD (yay for mountain biking vehicles with roof racks), then I can get busy on my BP. Excited about it, i'm hankering for some boost. This time of the big boy variety.

 

TURBO MIATA related question:

I've noticed my IAT corrections are off, i know this is the issue. The car runs great at 70+ deg IAT temps, when i drive the car with 40* IAT it's lean in cruise, going into boost it still hits the targeted low 11 AF/R - but cruise gets so lean it stumbles, and part throttle is off too.

Anyways, what is the proper way to go about tuning this? Do i need to ensure my base VE map is tuned with these corrections off? IIRC the corrections come on at 80 deg or colder. So, do I tune my base VE table when the IATs are >80, then adjust the corrections so everything is right when it's colder than that?

 

Should be tuned with the corrections off, and the IAT that is was tuned at should be 0 in the correction table with the corrections going to either side of it.

 

Thanks man, that makes more sense. That means I can effectively tune it with any IAT I want, and adjust corrections accordingly.

I think I'll tune it with IAT's in the 80's, because 90% of the time (read: spring/summer) it will be in that area. Then I can adjust corrections accordingly.