Question 12A661 inlet manifold

[UHR850]

As far as I know my inlet manifold 12A661 is Cooper 1000 but what does the P means and 1004

Kees.

[UHR850]

Here's what's come up what I found my self. There were two different 12A661 castings, a "P" and a "P2". At this point it's not clear what is different about the castings other than the P/P2 designation, From each of those castings there were two different manifolds made; the ones stamped 1004 which had only the PCV valve boss drilled and tapped (for 998 Coopers), and the ones stamped AEG347 which had both the bosses drilled and tapped (for Cooper S). The 12A661 variations are: P 1004; P AEG347; P2 1004; P2 AEG347.



viewtopic.php?f=3&t=24915

[Blacktulip]

Nice info. Thanks for sharing. I have the 998cc version

[dodge44]

Have an idea the early 'P' type manifolds suffered with fracturing on the clamp flanges and certainly the 'P' example I have has been welded. Picture attached of my P2 1004 manifold for comparison.

[jay weinstein]

They don't break on their own. When I was a dumb ass kid I was installing H4s on GOY764D and I
didn't align things correctly,tightened the manifold up and cracked it. Pretty sure I'm not the only one.
Cost me a six pack of beer to get it welded. 50 years ago!