The plate was cut on a waterjet out of 1/8th" Aluminum then polished. The plate lies in the recess below the center three valve cover bolts to allow the COPs to drop as far into the head as possible. The “studs” are made from bolts that are held with a nut, lock washer and red Loctite. Once in place the head of the bolts are sanded flat.

 

Very, very nice. :-) Why bolts and not panheads? Guess it doens't matter, anyway.

 

Yeap, I just had the bolts in a bin at my shop.

 

Do you have one more pic, showing how the end of the plate clears the cam belt cover/bulge?

 

Sure.

 

Why is there no washer on the front bolt? Would you like to join my international brotherhood of morning for all the broken miata dipsticks in the world?

I need coffee... Anyway, thanks for the pic.

 

The images were taken during construction. I have all three washers in place now. That is my third and last dipstick!

 

I lived with a broken one forever, maybe two years. Finally, I bought one. Then two days later, a friend broke that one. I lived with that for another year or two.

Now I bought another one, and I only have it on when the turbo heat sheild is in place, and I swap it for a broken one any time I'm working in the engine bay.

A friend has a metal one which I'm quite a fan of.....
-Abe.

 

spestis,

Are those plates available for sale. I'm pretty sure I saw someone doing a kit but can't find it now...

Yep, I searched...

 

Ooops.. If, how much?

 

The plates are $25 shipped within the US. It will be raw: un-polished un-tapped. You can paint it, brush it with a scotchbite pad (for a brushed look), or polish it with Mothers Mag & Aluminum Polish.

 

Hey I'd like to make some of those from electro-deburred and electropolished stainless. It would be a mirror finish if someone wants to send over some plans. Maybe we can work together on it.

 

Here is an image in CAD.

 

What a tease!

Haha, I don't have the COP kit, so I don't know any of the diminsions. If you make them I'll polish them and then people can get something really sexy. 14 gauge stainless would probably work. I can electropolish aluminum too, but the chemicals are nastier.

Travis

 

My thoughts on the plate I got, pics to follow upon request

It doesn't seem to fit a 99 (technically, a 2000 LS) head real well. It fits nice against the cam and belt bumps, and centers on the cover bolts well - but on my spark plug holes it seems the spacing is off. It's at the extreme end of the holes on cyl 1 and 4.

I gave it a quick polish, and it would take more to get it looking nice. There was something rust-like on part.

Lastly, I found the plate bent pretty easy - I had to tweak it with my hands a fair amount to get it straight, and then when I tightened down my coils, the plate bent from that.

All that said, the coils are held well in place, with some work it would shine up well. With the coils over it,you probably wouldn't notice they are actually in the wrong place - and the few mm they are off will be made up for by tilt in the coil.

If it were me, I'd likely make it out of steel, or thicker still. The edges are quite thin where the holes are punched. Tapping it went well, alum is a joy to work with.

It seems from your pics (more top-down-no-coil pics would help!) that the plate fits better in your car, though the spark plugs should be in the same spot across the NA/NB?

I probably shouldn't have used bolts, but studs as you did, but I don't like having those sticking up.

All in all it's nice, and the water cutting leaves a neat, 'sand blasted' looking finish on the sides.

 

The spark plugs should be in the same spot across the NA/NB as I have a 99 head and 94 valve cover.

 

Yeah! That had me really confused.

Here's some pics:

THIS is why you water jet. Can you tell which one I hacked out?




Ok, my first inkling that things aren't lining up right. It's hard to tell since my holes are pretty random, but on the motor they work fine.

Also, my COP mount points are vertical, not offset, so there's an obvious difference there. This is with 3 minutes with a die grinder and a buffing wheel in it. I'm sure with steel wool it would clean up just fine.


Here you can see my head seems to have shrunk in the wash. With the plate centered, the outer holes aren't quite in the right spot. Not sure why!


Lastly, with the #1 hole lined up, you can see the offset increasing with each hole. I have no idea how this looks on other heads, only mine.


Right now I have it mounted, it works when you split the difference and center it. It might be standing up on the lips, but not too bad. The forward facing plugs looks good.

I like that I can retain the rubber bumpers under the COPs, though I can do it on my set up too. For reference, here's my rough one:







Maybe later, I'll try putting the "forward facing" COPs on there, just to see how it looks.

 

What gauge wire should I use? I'm redoing mine right now and need to know.

 

For the triggers and tach, pretty much anything is fine as they're pretty low-current circuits. I think I used 20ga, since I had some lying around at the time. For power and GND, the beefier the better. I'd advise at least 18ga, preferably 16.

 

Thanks. I had mine done in 20 and 18 for ground but I want to clean it up a bit so I figured I'd ask and while doing it, do it the right way.