BMW M30 M90 Engine Heads Library

Krzysztof said:
This is the reason I have started that topic. The pain is most of the info from Experts like @sfdon, @Markos and Others (sorry for those I missed here) is hidden in many threads and it is extremely difficult to find it in a single place (FAQ section). Don't know how to tidy that up as it would require some effort and time from All.
My knowledge is poor but that motivated me to open that topic.
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Just keep dumping the data here. Even if nobody has time to curate a FAQ, at least the info is consolidated. FWIW - you don’t need to be an admin or moderator to put together a FAQ.

Lastly, I’m not an expert on this stuff. All of my info is recycled forum knowledge or phone calls with @sfdon. He and others that actually build these motors are the real experts. I can just as easily recycle bad info but try my best not to.
 
Markos said:
Just keep dumping the data here. Even if nobody has time to curate a FAQ, at least the info is consolidated. FWIW - you don’t need to be an admin or moderator to put together a FAQ.

Lastly, I’m not an expert on this stuff. All of my info is recycled forum knowledge or phone calls with @sfdon. He and others that actually build these motors are the real experts. I can just as easily recycle bad info but try my best not to.
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I agree on collecting the data but I think members should ask if a FAQ is warranted or we could be inundated with minor items, just my 2 cents.
 
Thank you @sfdon for your time and involvement in this thread.

I'm far for pushing this to be FAQ. I wrote a question to You All.

For me even this one is enough and valuable to many.

It is great we have person who has practical experience and are open to share it in some extent. I'm grateful anyone.

Someone like me might never witness most of the heads or camshafts.

It is difficult to list each and every part of engine as we somehow know (or at least) feel not only heads were changing, but also tiny parts still important.

The "nuts and bolts" stuff is expected to be - due to cross reference - easier to be clarified with parts catalog while heads and blocks casting numbers are quite often not possible to be identified with BMW Books.

Thanks once again. Let's wait if this thread will grow enough to be reedited into nice and comprehensive form. If that will not be the case it will just stay as it is but still very valuable for some of us.
 
I agree! What a wealth of information has been compiled in a short time period for this post.

SFDON as usual thanks for taking the time to post the pictures and explanations. You helped me properly identify the extra head and cam that has been sitting in my garage just waiting for the day I will need it. Thanks everyone for their contributions to this post. It was an awesome idea.
 
HB Chris said:
It needs to be organized a little better, right now it is Don’s stream of consciousness approach!
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Sure. As each thread need some time and interest of the others.

To All Interested...

What form do you think it should take?

A table?

Which information?
1. Pictures
2. Part Number / casting text
3. Models used/market
4. Years?
5. Possible application to E9 mods?
6. Problems
7. others?
 
Hi all,

I have a couple of heads to my disposal:

81 - 1 262 243 - E3/2 - height: 129mm - cil volume measured: 61.2cc (i suspect a bad measurement, will redo at some point)
IMG_20241106_132624.jpg

IMG_20241106_132632.jpg

IMG_20241106_132714.jpg

IMG_20241106_132735.jpg

IMG_20241106_132755.jpg
 
On my numbers matching 81 Euro it has an M90 in it with 175K miles on it. Everything was good as far as cracks go.. It is ported,cammed and new pistons about 10:1 or a bit more It goes like a bitch in heat but I am now wondering if I should have used a B35 head. I only have about 300 miles on it. The ports were opened but as far as I know, the engine builder used the M90 size valves. I am now switching ECUs I haven't opened them up yet but they are supposed to have been chipped The ECUs I bought are 008s( 2 of them) the reason being some of the later ones have a replaceable chip. I have Motronic 1.0 and these ECUS are plug and play . I will see what this does and if I am not happy with it I will go 1.3
 
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Bert, i'm not sure that you would benefit from it. my memory is that you will lose overall compression as there is more volume in head. sure, there are better springs, etc. ... but you can fix that in a rebuild of any head. our resident expert @sfdon can probably shed a little light on this subject as he has built a ton of m90, m30 engines of all varieties.
 
Agreed. The pistons are piano top, made by Diamond Racing Pistons. So I think on my M90 except for stroking,it's got what it can handle comfortably. I probably could have used a hairier cam but I felt a 284 was enough. Was impressed with Diamond. They may br a subsidiary of JE, I think. The difference is instead of waiting months I had them in less than 3 weeks. They were so pretty I just wanted to put them on the shelf and look at them
 
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Hi everyone,

I was not really sure where to post this but as it is related to cylinder head, I believe this tread is the most appropriate. Feel free to move it if needs be.

I am current restoring a M30B30 engine. The cylinder head is a 1 277 358 from 1984.

Interestingly, the valve stem seal is not the same as the one supposedly used on the original cylinder head (1 250 017). See below pictures:
- On the left, the valve stem seal recover completely the valve guide, but does not firmly hold onto it.
- On the right, the valve stem seal butt against the valve guide shoulder and firmly holds onto it.

IMG_6768.JPG IMG_7096.JPG

Also, the rocket arm axle is not fitted with the center plug (item 8 of the 11/23 in the part manual).
- On the right, the original rocket arm axle, fitted with plugs (external plug is screwed, center plug is press fitted)
- On the left, the 1985 rocket arm axle, fitted only with the screwed external plug)

IMG_7105.JPG


By the way, the reference inside the cylinder head is 13/1 M30:

IMG_7107.JPG
 
there is the “old” type stem seal which covers the complete guide. See also this picture of a 1977 type.
And there is the improved version which covers only a little bit. Those are the best and are a easier to install. You’re lucky if you have this type stem guide.

So it depends on which type stem guide is mounted and which type seal you have to order.

PS be aware not to damage the new seals when you slide them over the grooves!! There are very sharp and your seal will damage. Oil consumption!
I use a tape around the valve stem grove before putting the new seal over it.
 

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