Engine rebuild. Or not. But i'm hopeful.

U

underwaterthoughts

New Member
Messages
4
Reaction score
3
Location
Dubai, UAE
Hi Guys,

Wonder if i can pick your brains...

I'm in the process of rebuilding my 2800cs, but engine parts are an absolute nightmare to find. My head, camshaft, and pistons were done for so replacements needed to be found.

With no 2800cs heads availible anywhere i've bought a 1977 3.0 head (cast #1250199) with 46mm intake valves and 38mm exhaust valves - cam and rocker arms included.

It's looking more and more likely i'm going to have to get custom pistons made, I'd prefer to keep the car as original as possible, so 2.8 pistons. I'd guess reboring the 2800cs block from 86mm to 89mm to fit the correct geometry for the 3.0 head is more hassle than it's worth.

I wondered if anyone has any advice on the above? My garage is good but it's the first time they've worked on an E9 so i'm having to do a lot of the heavy lifting myself...

Thanks in advance!!!
 
Last edited:
underwaterthoughts said:
Hi Guys,

Wonder if i can pick your brains...

I'm in the process of rebuilding my 2800cs, but engine parts are an absolute nightmare to find. My head, camshaft, and pistons were done for so replacements needed to be found.

With no 2800cs heads availible anywhere i've bought a 1977 3.0 head (cast #1250199) with 46mm intake valves and 38mm exhaust valves - cam and rocker arms included.

It's looking more and more likely i'm going to have to get custom pistons made, I'd prefer to keep the car as original as possible, so 2.8 pistons. I'd guess reboring the 2800cs block from 86mm to 89mm to fit the correct geometry for the 3.0 head is more hassle than it's worth.

I wondered if anyone has any advice on the above? My garage is good but it's the first time they've worked on an E9 so i'm having to do a lot of the heavy lifting myself...

Thanks in advance!!!
Click to expand...
I have a complete USA 3.0 engine ready to ship..
 
highly recommend @sfdon's engine work, actually all of his work, but you won't find many more capable hands than his. finding one 'ready-to-go' is kind of rare ... beats the hell out of waiting a few months.
 
Hmm, custom pistons are not inexpensive and unless your car is low miles and in great shape otherwise, few people if, anyone will care if you've swapped your tired engine out for a larger, newer one. Our cars aren't like Porsches where adherence to originality is highly sought after.
The early heads have large coolant passages that are subject to cracking into the valve seat. There are two newer improved versions made after the first ones.
From the head FAQ on firstfives.org: "The approximate casting dates are, thru 78 will be the early head, 79-80 the intermediate one, and 81 and later the late one."
So the 1977 head you have may, or may not be of the newer, intermediate type. It's easy to tell, just look at the photos in the FAQ link below.

I picked up a 1983 head off of ebay just in case my 2800cs head is found to be cracked with I get into the engine. That was a decade ago, I don't know how the supply is these days. One drawback of the newer head is that it does't have the fitting for the mechanical fuel pump but I've already added an electric one to improve starting after long periods of storage.

I agree, with labor costs what they are and scarcity of parts making the search more time consuming and expensive, going with installing a known good engine would certainly be a tempting solution.
 
I don't know where you are located and how much of a rush you are in. At some point in the next 6 months I am pulling my 1973 3.0 CS with new Weber downdrafts. It will be looking for a good home. I am in Delaware. It was rebuilt 7000 miles ago by the BMW that sold the car new. The original owner was the owners family in CT. Will be a very good offer. Rather it went to a good home.
 
Rudy3.0CS said:
I don't know where you are located and how much of a rush you are in. At some point in the next 6 months I am pulling my 1973 3.0 CS with new Weber downdrafts. It will be looking for a good home. I am in Delaware. It was rebuilt 7000 miles ago by the BMW that sold the car new. The original owner was the owners family in CT. Will be a very good offer. Rather it went to a good home.
Click to expand...
Shipping to Dubai is likely to cost more than the engine!!
 
Thanks all - really good mix of advice. I’d prefer to keep the 2.8 if I can.

And yes, shipping to dubai if f’ing expensive!!!!

Has anyone had success mating the 3.0 head to the 2.8 block? I’ve heard it should be fine as the geometry is the same but I’ve just had a nightmare with some pistons I bought being too tall so slightly worried now…

From my (somewhat limited) research it shouldn’t be too much of an issue?
 
You must log in or register to reply here.
Back
Top