B35 Head Set-up for E-12?

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GripGreg
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B35 Head Set-up for E-12?

Post by GripGreg »

Hi Dudes.
I bought Bert's B-35 head and I need a cam & rocker arms to put it back together.
1) What size cam do I need to make it a lil hotter? Bert said maybe a 280 would be enough w/o going radical. I don't mind a lop though.
Also, what is the reliable name brand recommended? I know it was mentioned before.
2) Should I get a better set of rocker arms & where do I find them?
3) I'm guessing I need the gasket set for the B35, not for the 2.8, right?
4) And, with the updated head, should I get some hi-comp. pistons & how far should I go while maintaining my 2.8 engine?
5) I'm guessing you would recommend me boring out somethin' to match the head, right?
6) What about the intake said? Did I take on too much?? :roll:
Thanx in advance,,,,Greg
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Mike W.
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Post by Mike W. »

Uh, you're not planning on putting a B35 head on a 2.8 are you? It's got larger combustion chambers and you'll end up with something like 7.5:1 compression. Yeah, it flows better, but you need compression to flow.
Mike W.



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GripGreg
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Post by GripGreg »

Thanx for checkin' in, Mike.
Take a look at my #4 question.
Will you, please, answer all the questions?
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Falkenberg
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Post by Falkenberg »

Some euro 2.8 and 3.0 engines have a 272 degree cam :twisted:
So if you still have the old 2.8 head, you might want to to check the cam.
See faq: http://www.firstfives.org/faq/cylinder_ ... ad_faq.htm
1961 Simson AWO sport (Brasoveanca)
1968 BMW 114 2002
1976 BMW E12 528 (Malèna)
1987 Kawasaki GPz900r
1996 Moto Guzzi V75 PA NT
GripGreg
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Location: Long Beach, Cal.

Post by GripGreg »

I do, Falkenberg. In fact the factory motor is running nicely. I believe it's a US model because of the huge bumpers, though.
I just want to be ready for her when she goes away. Rosallina already has about 175,000 miles on her.
Maybe YOU can answer all my questions?
Thanx,,,,Greg
GripGreg
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Location: Long Beach, Cal.

Post by GripGreg »

I remember the cam is a Schrick! Thanx for all your help. :roll: :wink:
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Mike W.
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Post by Mike W. »

Sorry Greg, I did kind of just get focused on the title. :oops: I'll start, but it's gonna get complicated. A B35 head is less important on a 2.8 than a 3.5, it's got less air to try to push thru, so opening things up isn't going to make as much of a difference. Custom pistons, yeah, probably about 9.5:1 as plain old euros used 9.3:1 in E28 528i's. But that's 9.5 with the B35 head. Cam? I'd probably ping Paul Burke, you can find him occasionally on Mye28, he has a/some custom grinds and really seems to know his stuff. I have no shortage of confidence in my knowledge here and I think he forgets more in a day than I know. Short of that I'd go at least 280, at least if you don't need to smog it. :D You would need to port match the intake to the head, not easy as the shapes are different, not just larger.

At the end of the day, a plain old stock B35 3.5 is probably going to put out as much or more power as a 2.8 tweaked with a B35 head. With a lot less money involved.
Mike W.



02 525ita. Wife's, aka grocery getter
02 530i. New to the fleet, 3 pedals.
03 QX4, AKA the Datsun. Finally got the 4WD vacationmoble to stop smoking.
07 Xterra. Still on the DL, a purchase from hell.
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