I have two 2004 MSM heads. Different
 

One hads casting number "B P 1" other is "B P 2"?
What's ddifferen?

the casting

I see. Anything in the shape of the casting other than the numbers ans letters?

Are you typing on your phone? My spelling Nazi senses are tingling.

...Dimensionally and functionally same

Yes and thanks.

Likely functionally the same but I would guess you'd have a bimodal distribution of points if you measured the critical dimensions of a population of heads. Not that they'd be way out, but you can't just assume they're the same.

(for all intents and purposes they're probably the same.. maybe some Spec Miata folks actually care about the head castings)

Before or after they over-machine them and are disqualified?

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Way to go, resurrect a six year old thread, AND with a totally irrelevant post.:td:

He was posting a few comments in a row today in another thread here https://www.miataturbo.net/build-thr...04-msm-106032/
I'd say he's accidentally fallen for the old "Related Thread" when scrolling to the quick reply section at the bottom of the thread he was replying to. Has nearly caught me a few times before

*Edit: hehe yea, When I go to his build thread that he was posting in today, the Related Thread at the bottom is this thread.

Good pickup! I have never had that, as I am usually on a big screen, and never post on my phone, I can see that happening though

If he doesn't use 'new posts', he will be wondering where his post got to!!

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