• Tapatalk is being removed immediately. There are security issues and there is no justification for having it anymore. I apolgize to those die-hard Tapatalk users but you'll need to start using the forums mobile version instead.

Intake Modification for the B34?

ClayW

Member
Messages
53
Reaction score
8
Location
Silver Spring, MD
I’m swapping an E28 M30B34 into my E3. Does anyone know if I’ll need to modify the intake to clear the brake booster?

I’ve seen B35 I takes that needed modification, but the only B34 picture I’ve found (below) doesn’t seem to have been modified. Is there a size difference between the B34 (marked “3,2/3,5”) and the B35 intake manifolds?

 

ClayW

Member
Messages
53
Reaction score
8
Location
Silver Spring, MD
Pretty sure you'll need a Tii booster. Maybe the early thin type works too???
I think I have the early style booster. Eyeball measurements suggest that it will work in my favor.

Now I’m wondering if other, smaller boosters will work. I have a 2002 booster in my garage I assume less braking assistance, but that might be okay.
 

Attachments

ClayW

Member
Messages
53
Reaction score
8
Location
Silver Spring, MD
@ClayW,

Have you considered using the earlier intake manifold from a d-jet / l-jet motor? Clearance aside, the manifold looks period correct.
Yes, I have an L-jet manifold. I’m awaiting some machine work to be able to use EV1 style injectors, so I’m thinking about just using the E28 intake manifold to get the motor and transmission in the car as soon as possible. The long term plan is to use the L-jet intake, but I still have to solve a few details (fuel rail, intake boot, etc)
 

chope97

Member
Messages
125
Reaction score
22
Location
Silver Spring, MD
Hey Clay my 71 2.8 Bavaria has the smaller booster, it currently has a 3.3 from a 533i and a 5 speed it brakes just as good as my 73 3.0 auto which has the bigger booster
 

Bearmw

Member
Messages
43
Reaction score
10
Location
Western, MA
When speaking of the smaller booster are you referring to diameter or depth or both? Also, when did use of the "smaller" end?
 

ClayW

Member
Messages
53
Reaction score
8
Location
Silver Spring, MD
When speaking of the smaller booster are you referring to diameter or depth or both? Also, when did use of the "smaller" end?
I’m not sure when the smaller booster was replaced by the larger, but I imagine that it was somewhere in the 71 year model. Just a guess. My car is a 1970 2500, if that helps.

I was referring to the diameter. The E28 B34 intake didn’t clear the smaller booster anyway, but I found a Volvo P1800 booster, which is very similar to a 2002tii booster, and modified its linkage to fit.
 

HB Chris

Moderator
Site Donor $$
Messages
13,002
Reaction score
2,753
Location
Huntington Beach, CA
I think the e3 changed when the e9 did. The 2.8 motors had the thinner pancake style booster and the 3.0 motors got the much thicker booster.
 
Top