http://www.precisionshims.com.au/

Don't buy them out of 5.56 shims cause I need some! I'll actually have a whole stack left over from my head build.

Yup, thats what i found. I'll shoot them an email.

I called them earlier this morning... They have 5.6mm shims in stock and can ship them next day (plus overnight to me). I assume they'll ship to the US. If not you can use me as a freight forwarder.

I'll be ordering mine early next week after I have mounted all the valves and measured clearances.

Cool. I'll see what they can do, and maybe have you forward. Thanks for the help.

FYI I'm pretty sure Nial has the middle option. Don't be stupid, if your shims are on a lathe you're doing something wrong.

Lifters would be on the lathe :)

odd. Does that mean he has the 5.5mm shims?

I've got the packages from his shims at work, I'll double check tomorrow. I have 1 left from his build, since I measured 15/16 correct, and I have a bunch of unlabeled ones from Eddie's car and a few from an Elise, but I don't know what diameter they are.

Cool thanks. I can always just buy one for testing.

What I meant by this was that a "5.5mm" lifter stem that measure 5.56mm will almost certainly accept a "5.5mm" lash cap. These aren't so esoteric that someone makes a 5.5 and someone else makes a 5.6. On all the SUB setups I've done I've always set them up using Supertech LC55 caps (5.5mm). I'm sure you can find reference to someone running Mazdacomp lifters and LC55 Supertech shims. Ordering 5.6mm shims from overseas is silly IMO.

Alternatively, "search noob":

https://www.miataturbo.net/engine-pe...60/#post667694

Supertech 5.5mm shim does not fit on the lifter stem. So if anyone needs a single .8 5.5mm shim let me know :)

6mm shims on the valve for me it is.

The 5.6mm ahims fit nice. Precision Shims can suply up to 5mm shim height too which means I only need to run one shim rather than the two previously.

$9AUS per shim. - GST and USD conversion would place them around $6US each plus shipping.

Quote from precision was ~140 shipped. I'll stick with the supertech 6mm. They should fit on my stock valves just fine.

Color me surprised.

It was very close. And I didn't test all the shims. But it just kind of rolled around like it was about to fit on, but wouldn't slip on.

0.06mm won't slip fit regardless of how much persuasion is used! It's amazing that after 25 years of miata / mx5 development and use in motorsport these issues aren't widely known.

Eh, it kinda was a known issue. The reason I only bought a single shim was because I thought it might not fit.

I looked at the stock valves that I'm using and the 6.0mm shims should work just fine on top of the valve. If I need to change things down the road so be it. I can always toss the lifters in the lathe, but thats not needed right now.

I can't run 6mm shims on my RB26 intakes valves because they sit so close to the top of the retainer. That's what you get for running oddball stuff I suppose. The previous valves had been machined to fit the Mazda valve cotters but because I bought nitrided Supertechs my lathe cutters just bounce off them. This means I have to run the Nissan valve cotters which have the 'D' locator a few mm higher on the cotter.

Anyway, bigger 5.6mm shims work better anyway. I now have 10 days to get this head back together before my next event.

Is that the difference between the Supertech SUB Lifters (5.5 lash caps used on lifter bucket) and the MMD SUB Solid lifters (6mm caps on valve)?


I was curious why there where $100 price differences floating around.

One is built by supertech the other by Maruhahaha.