I commend you on your work benchmarking all the different variants of the manifolds. After doing a few benchmarking exercises at work on a world wide basis I know how much work they really are.

Now to throw a wrinkle in this, once the chart is fairly finalized to put it out one of the bigger UK forums for comments and more input. (sorry, I sound like I'm at work).  I know we have quite a few in the UK here on the board, but I wonder how much more info is out there that we're not tapping into.  dan

"I don't know much, but what I do know I know little of "

After several hours sorting all the info. submitted the chart has been updated, and the latest version is attached.  There is more to do and a few gaps to fill, see the notes at the end of the chart.  This really works better with the photos, and I'll try to repost tomorrow with the photos.  I'm a little bleary-eyed right now, and there may be a few typos in the chart too.

Given the interest and all of the excellent input I thought I'd post this part tonight.

Concerning the "Evolution" manifold, it appears that it could be #9 or #10 on the chart.  The picture in the homologation papers is kind of fuzzy and both of these manifolds have similarities to the picture.  More on that tomorrow.  Note that it's not really named the Evolution manifold.  That's the title of the page in the homologation papers, an evolution of the vehicle from the one originally homologated.  The papers for almost any car will contain evolution parts.

I hope this thing is legible!

Here are several of the photos of a 12G 2463 that Eduardo at CooperMk1works e-mailed directly to me.  Another example of the factory grinding off one number and stamping another one.

Eduardo, can you tell what the ground off number might have been?  I'm guessing AEG573.

MacDhaibhidh, 12G 586 is a new number in the mix.  Can you provide any details per the columns on the chart and possibly a photo?

I was most interested in Spitz's photo, as my 1275 S  has as its alternative manifold ( ie it came in a box of parts) an AEG 573, which does not figure in the table. is this the evolution manifold?

Chris

proof of changepoint

 Tulka

Eduardo, I will post your pictures later today.  These are the first shots of a 12G2463 that have been provided.  It has rectangular carb mounting faces and HS2 bolt pattern.  That must have become the fairly standard pattern towards the end of the S production.

Steve, The early and late 998 references in my chart are from the BMC factory parts manual.  There were change points based on engine number.  I'll post those numbers later today and will probably incorporate them into the chart.  Similar engine numbers are provided for the S models, at least the Mk. I versions that I have the parts books for.  If there is interest in having all of the change points for the various engines we can probably come up with most of them.

Have to hit the road now, will provide the above updates this afternoon.

slight hijack.. coopermk1works -eduardo, please see my thread on a sunroof. Are you aware of this product & availablity? (Made in Spain)

Now back to our our regular programming....

Make it idiot proof, and someone will make a better idiot....

 

Excellent topic! Congratulations!!! I have a 12G2463 manifold. It's original casting number was erased, but you still can see a 'P'. It is stamped 12G2463 upside down just below the original casting no. on the cylinder head side of the manifold. It has two vacuum ports, ring mounting, and the carb mount face is rectangular. S&M Minis, I have sent some photos directly to you. All the best from Portugal, Eduardo

Hi

I see that there is mention of early and late 998's using different manifolds. Can anyone tell me what early and late refer to. In the UK it would be across a large time frame but here in Oz we are looking at '64 - '65.

Cheers

Steve

I have a 12G 586 for whatever?

Speed's Expensive........How Fast can you afford to Go??   

S&M Minis - Yes, the P2 casting has the upside down MOWOG marking. Thanks for posting my photos.

BruceG

Here are the pictures that BruceG provided for the AEG 347 on the 12A661 P2 casting.

There are no visible differences between the P and P2 castings in a photo comparison.  The markings are cast differently on the P manifold, 12A 661 on a raised pad with the P below it.

Bruce, does your manifold have MOWOG or any other markings on it?  The P casting has MOWOG upside down on the back of the balance tube.

S&M Minis - thanks, have emailed photos to you.

BruceG

BruceG, No photos yet.  If you want to e-mail them to me I can post.

Here's what's come up on your manifold via this thread and direct e-mail I've received.  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, pictures are still coming in.  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).  All four variations have been identified and I think we have pictures of all four coming.  The 12A661 variations are: P 1004; P AEG347; P2 1004; P2 AEG347.  If anyone has both the P and P2 castings could you put them side by side and see if there are any obvious differences?

And not a pedantic response at all.  The chart will have some major changes made to it based on the impressive and helpful input I've received.  I have to get some real work done first, so please bear with me.

Trying to be helpful, not pedantic, but I have a manifold with 12A661 P2 casting marks, and AEG347 stamped, the only 12A661 P2 in the most excellent chart is stamped 1004. Both vacuum ports are drilled. I don't know the origin of this manifold. I will try to post a pic, but have had not been able to recently.

BruceG

<edit> Playing with photos

 

 

 

 

 

My RAC paper about the evolution manifold is dated 1st March 1968.I think this fits in with Spitz AEG 573 manifold.

Tulka

MOWOG marked.
AEG573   6" between studs

1130cc, 12g295, SW5 cam, LCB, Twin 1¼ SU's, CA spec.

I am making zero progress on a couple of reports that clients are expecting tomorrow, but the distraction has been terrific!

There's a post on the Vintage Mini Racing Board where the member describes the manifold xcc has posted a picture of (original number ground off and AEG 179 stamped in its place) and he further states that the manifold is original to his 1071 S (i.e., the first S model).

This is pure supposition, but I would propose that BMC modified the casting cores for the 12A309 manifold (997/998) to include a brake booster vacuum boss when the 1071 came out.  If the boss was drilled and tapped for a booster on an S installation (see xcc's picture) the casting number was changed.  If the boss wasn't drilled and tapped (for a 998 Cooper installation) the number stayed as-cast (see Tulka's picture).

Does anyone have a AEG 179 with the numbers cast in?  Or did it go from this grind and stamp approach straight to the 12A661 casting with two vacuum port bosses?

This is an original C-AEG489 from above, BA82357 might be the drawing or mould.

 Tulka

Somebody on the night shift forgot to change numbers?

 Tulka