cylinder head swap

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Sharky1980
Posts: 10
Joined: Thu Mar 28, 2019 1:46 pm
Location: Seattle, WA

cylinder head swap

Post by Sharky1980 » Sun Jul 14, 2019 11:00 am

Hello. I'm new to the forum, but have had my 1980 528i for a few years now, and spent a lot of time revisiting the FAQ section. i was my daily driver, until it blew a head gasket. Now I'm currently in the middle of a head swap, from the early casting [1 250 019] to a later casting, from a '86 635CSi [1 277 358]. Preparing for re-assembly, I'm comparing the two heads and head gaskets, and noticed a difference that I'm concerned may be an issue. The 3.5L head [and blocks] have a small water jacket passage way, approximately 6mm in diameter, tucked up between the cylinders on the exhaust side. There is also a corresponding space in head gasket, however, the 2.8L block is solid. I'm concerned this will cause problems if I don't block it off in some way. Have any of you seen / addressed this?
See attached pics, and thanks!
IMG_0304_m.jpg
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IMG_0305_m.jpg
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IMG_0307_m.jpg
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- 1980 528i
- 1983 944

Sharky1980
Posts: 10
Joined: Thu Mar 28, 2019 1:46 pm
Location: Seattle, WA

Re: cylinder head swap

Post by Sharky1980 » Sun Jul 14, 2019 11:01 am

...and here is a pic of the block
IMG_0308_m.jpg
IMG_0308_m.jpg (99.38 KiB) Viewed 509 times
- 1980 528i
- 1983 944

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Mike W.
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Re: cylinder head swap

Post by Mike W. » Sun Jul 14, 2019 1:15 pm

Not to worry, just bolt it on up.

You do have the right cam in there or adapter nut, correct?
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter

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maybeillbuyit
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Location: Vancouver BC

Re: cylinder head swap

Post by maybeillbuyit » Sun Jul 14, 2019 1:30 pm

I notice piano head pistons, so thats a euro dirty engine? :shock:
1977 530i another project
1979 635csi Euro "project"
1987 635csi

Sharky1980
Posts: 10
Joined: Thu Mar 28, 2019 1:46 pm
Location: Seattle, WA

Re: cylinder head swap

Post by Sharky1980 » Sun Jul 14, 2019 3:09 pm

Thanks Mike W. I had the machine shop swap cams, so yes, I have the correct distributor drive / cam.
- 1980 528i
- 1983 944

Sharky1980
Posts: 10
Joined: Thu Mar 28, 2019 1:46 pm
Location: Seattle, WA

Re: cylinder head swap

Post by Sharky1980 » Sun Jul 14, 2019 3:23 pm

maybeillbuyit - um, I dunno. This is my first BMW [car], so I still have a lot to learn.. Are piano tops only euro / high-compression? I know it's not the original engine, but haven't dug in deeper that that yet.
- 1980 528i
- 1983 944

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maybeillbuyit
Posts: 185
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Location: Vancouver BC

Re: cylinder head swap

Post by maybeillbuyit » Sun Jul 14, 2019 5:59 pm

I'm not positive myself. I've always heard about piano top pistons in the high comp euro engines. No first hand experience myself. I didn't know they came in NA engines. Worth looking into.
1977 530i another project
1979 635csi Euro "project"
1987 635csi

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maybeillbuyit
Posts: 185
Joined: Mon Feb 17, 2014 12:26 am
Location: Vancouver BC

Re: cylinder head swap

Post by maybeillbuyit » Sun Jul 14, 2019 6:17 pm

OK so I was curious about those pistons and asked my BMW guru buddy and he said all b28s had those pistons so its nothing special. Sorry I got over excited. Another guy I know found a 528i in a yard a while back with the head off and asked me the same thing.
I'll be doing the same thing later on my car. I think the guides are worn and need replacement. Instead of redoing the old existing head I've got a head from an 81. Did you replace the valve guides?
1977 530i another project
1979 635csi Euro "project"
1987 635csi

User avatar
Mike W.
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Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Re: cylinder head swap

Post by Mike W. » Mon Jul 15, 2019 11:17 am

US spec E12 2.8's had a small raised piano top crown, 2MM IIRC. Early US 2.8s, such as 69-71 E3s and E12 euro had higher compression, 9:1 pistons with a larger crown, ~6MM or so. The pic looks like more than 2MM but I can't tell for sure.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter

Sharky1980
Posts: 10
Joined: Thu Mar 28, 2019 1:46 pm
Location: Seattle, WA

Re: cylinder head swap

Post by Sharky1980 » Tue Jul 16, 2019 12:29 am

Measured my pianos: 6mm tall. Looks like I lucked into higher compression. Sweet!
EA38B08F-2F27-426F-BB39-5574EA738F7A.jpeg
EA38B08F-2F27-426F-BB39-5574EA738F7A.jpeg (129.36 KiB) Viewed 485 times
- 1980 528i
- 1983 944

Sharky1980
Posts: 10
Joined: Thu Mar 28, 2019 1:46 pm
Location: Seattle, WA

Re: cylinder head swap

Post by Sharky1980 » Tue Jul 16, 2019 9:32 am

maybeillbuyit wrote:
Sun Jul 14, 2019 6:17 pm
OK so I was curious about those pistons and asked my BMW guru buddy and he said all b28s had those pistons so its nothing special. Sorry I got over excited. Another guy I know found a 528i in a yard a while back with the head off and asked me the same thing.
I'll be doing the same thing later on my car. I think the guides are worn and need replacement. Instead of redoing the old existing head I've got a head from an 81. Did you replace the valve guides?
According to the machine shop, my new-old head was is pretty good condition already, so no valve guide replacement.
- 1980 528i
- 1983 944

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maybeillbuyit
Posts: 185
Joined: Mon Feb 17, 2014 12:26 am
Location: Vancouver BC

Re: cylinder head swap

Post by maybeillbuyit » Tue Jul 16, 2019 11:58 am

OK, lucky you. Saved some expense there. I had the same on a previous head redo
1977 530i another project
1979 635csi Euro "project"
1987 635csi

User avatar
maybeillbuyit
Posts: 185
Joined: Mon Feb 17, 2014 12:26 am
Location: Vancouver BC

Re: cylinder head swap

Post by maybeillbuyit » Tue Jul 16, 2019 11:59 am

Sharky1980 wrote:
Tue Jul 16, 2019 12:29 am
Measured my pianos: 6mm tall. Looks like I lucked into higher compression. Sweet!
EA38B08F-2F27-426F-BB39-5574EA738F7A.jpeg
OH wow, thats awesome, Mike whats the HP difference in those engines?
1977 530i another project
1979 635csi Euro "project"
1987 635csi

User avatar
Mike W.
Posts: 2447
Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Re: cylinder head swap

Post by Mike W. » Tue Jul 16, 2019 11:53 pm

maybeillbuyit wrote:
Tue Jul 16, 2019 11:59 am
Sharky1980 wrote:
Tue Jul 16, 2019 12:29 am
Measured my pianos: 6mm tall. Looks like I lucked into higher compression. Sweet!
EA38B08F-2F27-426F-BB39-5574EA738F7A.jpeg
OH wow, thats awesome, Mike whats the HP difference in those engines?
Not a ton, euro 528i was 177HP, US 169HP. Still a little more fun.

On valve guides, in my experience the seals are more important than the guides, so I assume you are using new seals?
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter

Sharky1980
Posts: 10
Joined: Thu Mar 28, 2019 1:46 pm
Location: Seattle, WA

Re: cylinder head swap

Post by Sharky1980 » Wed Jul 17, 2019 12:34 am

Thanks for the info Mike!

Yes, the shop installed new valve seals. Good to go.
- 1980 528i
- 1983 944

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