Webers Carbs... Do Webers fit directly onto the Zenith Manifolds?

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execmalibu

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I have extra Weber Carbs and they came in a box with Manifolds, Linkage and misc other parts. The manifolds look like standard BMW Zenith manifolds.

To swap from Zeniths to Webers what is involved? Do I need to swap manifolds, linkage etc?
 
If it matters to you you'll have to cut the stock air cleaner assembly to fit them, are the zeniths not running well?
 
I was able to fit the Webers without modification to the air cleaner assembly. I do know that some coupe owners have issues with the assembly being too high but mine fit, albeit very snug under the hood. in fact the under hood insulation had an imprint of the forward half of the air cleaner.

Thanks,
 
They should just bolt right up but ...

you should always check that the carb to manifold ports mate nicely. If not you should use a grinder or hand files match them. I needed to do this when I adapted a 32/36DVG to a 2002 manifold many years ago.
 
Carb to Air Cleaner adaptor

The JAM Engineering conversions allowed the use of the stock air cleaner. I've been told that this was the only conversion that CA air control folks would allow, so there may be some available if your carbs don't already have the JAM parts. They are easy to spot since "JAM" is cast into the AL adaptor that sits on top of the Weber carb.
 
Also, as I remember there was a thick bakelite block between the intake manifold and the carburetor on the stock Zeniths. The thickness was about 1/2" or so. Those need to be removed and thinner (about 1/8") spacers used to accommodate the air cleaner assembly in whole.

Thanks,
 
Yes, 32/36DVG downdraft webers will bolt to the stock intake manifold.

The JAM kit adapts the air stock cleaner to the Webers. It does position the air cleaner rearwards. On my car, shifting the cleaner back caused it to interfere with the lens of the underhood light.

The stock throttle linkage sort of works, but it can over-center with Webers. Retaining the thick insulator, to position the carbs as high as possible can help to minimize this. But be sure to check that the linkage doesn't jam in the fully open position!
 
This happened to me on the highway in my old coupe after I installed Webers - scared the $@!T out of me. Having had both Webers and Zeniths, I prefer properly rebuilt Zeniths. Disassemble them, hone the surfaces flat and true, rebuild with a quality kit, and adjust them. IMHO they got a bad rap back in the day because of the warping and we simply swapped them out for Webers. My rebuilt Zeniths are going on a year without being touched and they work great. Now triple Webers on the other hand...that might be fun.

jmackro said:
But be sure to check that the linkage doesn't jam in the fully open position!
Click to expand...
 
I have the JAM Engineering adaptors on my coupe. Easy to install but the holes in the stock air cleaner brackets have to be enlarged to accept the hardware. And yes, the entire air cleaner sits further back, making it impossible to secure the latch closest to the fire wall. The air cleaner also sits a bit high as mentioned, leaving a nasty impression in the hood insulation.
 
Stevehose said:
This happened to me on the highway in my old coupe after I installed Webers - scared the $@!T out of me. Having had both Webers and Zeniths, I prefer properly rebuilt Zeniths. Disassemble them, hone the surfaces flat and true, rebuild with a quality kit, and adjust them. IMHO they got a bad rap back in the day because of the warping and we simply swapped them out for Webers. My rebuilt Zeniths are going on a year without being touched and they work great. Now triple Webers on the other hand...that might be fun.
Click to expand...

+1 for zeniths
it took a while to understand, and synchronize, but, they work great !
tell me if i can help, i have really fresh knowledge to share !
 
Just to keep the debate going, I have to say that my Weber 32/36's work pretty well too. The "turning point" in my Weber experience was getting a pair of 32/36's with manual chokes from Pierce Manifold. See: http://www.piercemanifolds.com/product_p/22680.005.htm

22680.005-2.jpg

My biggest problem with both Zeniths and coolant-operated Webers was that the car was difficult to start, and ran terrible when cold. Going to a manual choke fixed this.

When Zenith offers a manually-operated choke, I'll switch back :mrgreen:
 
jmackro said:
Just to keep the debate going, My biggest problem with both Zeniths and coolant-operated Webers was that the car was difficult to start, and ran terrible when cold. Going to a manual choke fixed this.

When Zenith offers a manually-operated choke, I'll switch back :mrgreen:
Click to expand...

exactly for the same purpose: just sportive debate...;:-D

i understand the difficult to start, but in my case the rebuild, cleaning and substitution of several parts (using two carbs as donors), made the miracle, now the starting is great ! and so nice to see how the hot comming from the coolant operates and compensates the whole thing alone until the warm operating conditions came, is a work of engineering !

probably the problem is to find enough spares to do this, so i was lucky !

you know everyone is the sum of himself and his circumstances

regards
 
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