Here is the video:

 

Difficult to tell for sure on the video but it appears that the valves do not have much margin, looks like they may have been ground to much.
At any rate you should pull the head to get it fixed.

 

Does anyone else get seasick watching that in full screen?

I was hoping to see the valve seats in clear detail. I guess the head will be coming off regardless of what you see at this point.

 

If I have to chuck all the Supertech valves, would it be stupid to install the stock valves back in the head?
They were OK when I pulled them to make room for the Supertechs.
(and, I would not just pop them in. The machine shop will go over them of course.)

Spending $300+ on valves - on top of all the other stuff - is a bit much at this time.

 

I am still not sure what exactly is going on here. If you've gotta fart around with the valves, might as well do it with the Supertech over the stock ones, right?

Is the general consensus just that the lash is all messed up? I'm confused as to why it would misfire when cold but disappear when warm.

Have you pulled the head yet?

 

You should be able to machine the Supertech valves back into tolerances unless things are bad wrong.

 

That's a valve relief!

 

Snowstorm's over, weather report says 50F and sunny for tomorrow, and I will be able to pull the head finally.
Working outside sucks sometimes.

I will post all dirty details here as soon as the head is out.
I just hope my valves are not "tulipped"...

 

Pulled the head, here are the pics:
Please comment...
(Also, see the two short videos in the next post)





























And, I checked the clearance on the offending valve one more time, just to be sure.
My thinnest feeler gauge is 0.05mm (0.001969"), and I cant even get that one in there:

 

I guess the guides are shot, as well:

(You might wanna turn the sound off, wind chime is way too obnoxious.)

 

Looks worse than I expected to see. It's difficult to tell with the carbon build up but those profile shots really show the condition of the back cut in the shadows they cast. Although .012" (at minimal) doesn't seem like much, it's evident that the valve and likely the seat are damaged.

 

I hated reading this thread.

Similar setup - wiseco's, eagles, arp, 99 head, +1mm supertechs. Cold miss. My brother rode with me and said it seemed down on power from the last time he rode with me (6+ months ago).

Ignored it while I got the car past (and passed) emissions. Car started puking oil out of the catch can and rear main a week later. Finally had a chance to poke it tonight.

Compression was 120, 150, 150, 150. Leakdown (via crappy HF gauge at 15psi) was 95%, 55%, 45%, 55%. Loosened the caps and retest - 25%, 26%, 24%, 27%. Well, at least it's not the rings.

Exhaust valve clearance is ***** on, .30mm all day long.

Intake - couldn't get the .04mm feeler between 6 buckets. The other two were .06 and .08. FML.

Looks like I need a new machine shop. Though I did promise myself if I ever had to pull this engine again, a V8 was going back in its place.

 

Why does it look like I'm not looking at the tip of the cam lobe? We should be at this angle.

 

The tip of the cam lobe is pointing (sort of) straight at the camera.

 

Gentlemen,

After buttoning the head up with my used original valves, I knew I would have to go in once again and make things right.
(I was really pressed for time then. I had to get the car back on the road ASAP)

Needless to say, I am not working with that machinist anymore.
(For the record, he cut the old valves razor thin - they are pretty much on borrowed time. And, I am seeing excessive EGT levels during fast cruise and under boost.)

I have put together a list of parts. I will take the head apart when I have everything in hand over here.

Please tell me what you think, it will be much appreciated.

• Supertech MAEVI-1206 - Exhaust valves Inconel (+1mm)
• Supertech MAIVN-1206- Intake valves (+1mm)
• Supertech SPR-2082-K - Inner valve spring kit (to move up to the "light double" setup)
• MiataRoadster MR-BVG-16 - Manganese-Bronze valve guides
• Fel-Pro HS 9717 PT-3 - Head Gasket Set
• Sealed Power 245-1250-56 - Exhaust Valve Seat Set
• Sealed Power 245-1437-74 - Intake Valve Seat Set

I'm really hoping this will take care of my problems once and for all.

 

For the record, Bryan at FAB9 has been tremendously helpful with everything, at every step of the way.
Thank you. (I know you post in this forum)

 

I feel for you. I really do. I changed machine shops too and the '99 head on the Red car (with OEM valves but good machining) has been solid since.

I've recently gotten the Silver car back on the road -- street driving only. The motor (including the head) was done by that first machine shop. I live in fear -- but hydraulic lifters are much more forgiving. So far so good (3K miles).

 

Your parts list looks great. I am happy I have the light doubles after I missed a shift this weekend at the track. Good insurance.

 

I would recommend changing valve seals as well unless they were done before. Fairly cheap (especially compared to the other stuff) and a known weak point.

 

That goes without saying.
Those seals come in the FelPro gasket kit.