BMW M30 M90 Engine Heads Library

[Krzysztof]

Topic about the engine heads is very vital and it is repeating from time to time here.

I was considering if maybe it would be good idea to sum up all the M30/M90 heads with some comments from You, experts.
Sooner or later every user of old version will be forced to consider changing it or the whole engine to newer type.
The know how of the compatibility or required changes is limited.

What do You think?

Here are two examples, well pictured:

1. BMW # 1708497









2. BMW # 1277358

 

[Krzysztof]

3. BMW # 1708843

 

[Arde]

Wow, that library is heads and shoulders above what we had .

Here is the head I got from SFDon for my E24, and is a DOT-R head.

New item by Ariel

photos.app.goo.gl

New item by Ariel

photos.app.goo.gl

The E9 head is a also a DOT-R head the PO got as a new short block, but I have no good picture to share.

 

[HB Chris]

This is heady stuff after all.

 

[eriknetherlands]

Great idea!

For instance, I'd use it to determine what's in my car, as I think it has been replaced, but I have no knowledge.
With a bunch of pics, and desriptions, I could use it to identify what's i stalled in my car.

Secondly, I think it might be a good location to also consolidate some notes on things to consider when looking for a new head, and how to assess the state (health if you will) of a head. @sfdon already generously shared many pics and explanations in various threads, so some can be harvested from there.

P.s. In these woke times, I feel must denounce cannibalism, but I do understand that others collect heads as a hobby.

 

[Ohmess]

Kris - great idea, but I have a suggestion. It would be helpful if you were to provide an overview of some kind, and to characterize the heads you have pictured in accordance with your overview. For example, I know there are early m30 heads with slots for coolant passages that were not the best, which were often replaced if the owner had overheating problems with later heads. And in addition to the heads found on later M30 engines, there are Spanish made replacement heads. I also know that the b35 heads have a different combustion chamber and larger intake valves. So, with my limited knowledge, I can get to four groups or categories. I'm sure there are more.

 

[Markos]

Keep going with this thread and we can consolidate the findings in a FAQ.

Also there is this on firstfives.org

M30 Cylinder Head FAQ

 

[Krzysztof]

Great idea!

For instance, I'd use it to determine what's in my car, as I think it has been replaced, but I have no knowledge.
With a bunch of pics, and desriptions, I could use it to identify what's i stalled in my car.

Secondly, I think it might be a good location to also consolidate some notes on things to consider when looking for a new head, and how to assess the state (health if you will) of a head. @sfdon already generously shared many pics and explanations in various threads, so some can be harvested from there.

P.s. In these woke times, I feel must denounce cannibalism, but I do understand that others collect heads as a hobby.

I'm happy you find it useful.

I'm on the same page with my doubts which head is which are what to look for and which is to be avoided.

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.

It is more and more difficult to find any M30 parts for resonable money. And once they are appear it is good to know if it worth to buy for our project or no.

How to follow up Guys?

 

[Krzysztof]

Kris - great idea, but I have a suggestion. It would be helpful if you were to provide an overview of some kind, and to characterize the heads you have pictured in accordance with your overview. For example, I know there are early m30 heads with slots for coolant passages that were not the best, which were often replaced if the owner had overheating problems with later heads. And in addition to the heads found on later M30 engines, there are Spanish made replacement heads. I also know that the b35 heads have a different combustion chamber and larger intake valves. So, with my limited knowledge, I can get to four groups or categories. I'm sure there are more.

This is exactly the reason I have initiated that topic.

It was also a discussion about FAQ about the engines or blocks.

The problem is BMW part numbers are difficult for finding. Most of them are not in the part catalog (internal or overdue numbers).

I think this is the right time to list them all and make some expert-based judgement or at least to find what we know about the numbers based on historical discussions on this but also other forums.

How to make it efficiently and can We count on some professional comments about at least some of the heads? I'm open to look for some info but in the end I'm not and expert about that topics unfortunately.

 

[sfdon]

Let me state very clearly- I make mistakes… I can be wrong all day long.
Any comments, corrections and additions are great!



There are 3 different intake ports on our big six heads.
Early, middle and late. Here is a pic of a b35 head with all 3 gaskets.

 

[sfdon]

Heads have identifying castings. Some examples…the turbo head has “turbo” cast on intake side at rear. The DOT replacement head had a yellow sticker at the top on the intake side- it was a result of DOT anti theft regulations.

m30
m90
b35
turbo

 

[sfdon]

M90 heads have twin cooling passages between the cylinders.

 

[sfdon]

There were early water jackets that cracked and later that didn’t.

 

[sfdon]

There were no dimples in the beginning, small dimples next and finally- big dimples.
Dimples showed casting thickness without needing to measure.

 

[sfdon]

Heads have casting dates. You can have an 1983 carbureted engine head on a 1973 engine. And a FI head head on a 1973.
Check the date in circle between #1 and #2

BMW made replacement heads continuously.

 

[sfdon]

Anybody want a cam picture book?

 

[sfdon]

Cams….

3 different cam end pieces.

Early forked cam

One year “H” cam

Motronic style cam

View attachment 155703

 

[sfdon]

Schrick makes sport cams for all three versions

 

[sfdon]

There are many different factory grinds.

3
7
8
K
H
M
B

M is USA early Motronic - 260 duration
K is 80’s euro and late USA - 264 duration
H is 1982? One year only in USA?
3, 7, 8, B are 272 duration

 

[sfdon]

Anyone want tranny picture book?