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Discussion Starter · #1 ·
If I decided to switch from a Solex to a Weber Carb, is an adapter plate needed? And if so, where would I get it?
 

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32/36DGxV, 38DGxV or 40DFxV

Mogus said:
If I decided to switch from a Solex to a Weber Carb, is an adapter plate needed? And if so, where would I get it?
Not needed for the 32/36DGxV, 38DGxV or 40DFxV Weber carbs . . . bolt right on to stock manifold! :)

Do have to port manifold at carb mount to clear larger throttle plates though.
 

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I am doing the same thing. I have a weber 32/36. By porting you widening the holes on the stock intake manifold right. If so what would be a good method to port these intakes? ALso the throttle plates on a weber are underneath correct. With the existing manifold the ports would interfere with them opening and closing right.
 

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boomerang opeler
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opelagain said:
I am doing the same thing. I have a weber 32/36. By porting you widening the holes on the stock intake manifold right. If so what would be a good method to port these intakes? ALso the throttle plates on a weber are underneath correct. With the existing manifold the ports would interfere with them opening and closing right.
a dremmil with a small flap drum (a drum with flaps of caberundum paper bonded on ) will sort the manifold (do it off the car so you can clean it without any muck getting in the engine)
and yes about fowling the plates
 

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Opeler
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This thread has me curious. I replaced my solex with a 32/36 two winters ago and made no mods to thick and thin gaskets or the intake. At that time I hadn't read about porting the intake or opening up gaskets to match the webber throat.(Novice) I haven't noticed any problems with the butterflies hitting anything. I did have to do quite a bit of grinding to the webber air cleaner adapter after having it milled though. If I pull the carb to do some mods, can I reuse the gaskets?

Wayne

Mogus - What model Opel do you have and where abouts do you live in Iowa?
I have a 70 GT and live in the NE part of the State. Don't see to
many members from around these parts.
 

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boomerang opeler
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wayne if you keep the phenolic spacer from the weber it fits ok if you use the solex one or no spacer you have to port it or the spacer
its a must to use the spacer to stop the heat transfer boiling the carb dry unless you need the space under the hood
 

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Opeler
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Baz

I must of got the weber pheonlic spacer. This was the first I read about the problem. Thanks for the explanation.

Wayne
 

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Discussion Starter · #8 ·
Port

I am not a mechanical whiz but I take it that you mean that the Manifold will have to be enlarged? How is that usually accomplished. Will it have to be done by a vertical boring machine? Can it be accomplished by an amateur with a grinder. Help
 

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Discussion Starter · #9 ·
wayne70gt said:
This thread has me curious. I replaced my solex with a 32/36 two winters ago and made no mods to thick and thin gaskets or the intake. At that time I hadn't read about porting the intake or opening up gaskets to match the webber throat.(Novice) I haven't noticed any problems with the butterflies hitting anything. I did have to do quite a bit of grinding to the webber air cleaner adapter after having it milled though. If I pull the carb to do some mods, can I reuse the gaskets?

Wayne

Mogus - What model Opel do you have and where abouts do you live in Iowa?
I have a 70 GT and live in the NE part of the State. Don't see to
many members from around these parts.
Wayne,

I live in DeWitt, IA. I just bought a very nice 71 Opel 1900 sedan. I love the car but it runs like a sick dog!!! So I am trying to get the carb fixed and see if that solves my problem.

Where are you located?
 

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Discussion Starter · #10 ·
Let me see if I understand this correctly. If I use the phenolic spacer that comes with the Weber Carb then I will not have to port the manifold?
 

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Opel Adventure # 77 NC
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Mogus,
I am in the Quad Cities, PM me your phone #. I should be able to get your sick dog running a little better.
Kevin
 

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Moderator's Note: Two strikes on the niceness counter, both posts unceremoniously removed

From what I have seen, as long as you use the 32/36 Weber, and the matching spacer gasket, the butterflies will not hit the intake. But if you use the stock 32/32 Solex gasket, the smaller hole will both foul the secondary plate, and cause "reversion" (I think that is the term) by backing up flow from the second throat.

Now the 38 DGAS is another story...
 

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I have never had a phenolic spacer on my Weber 32/36. I have great torgue on the low end but my top end sucks. If I understand correctly from Ralley Bob's postings, by increasing the height of the Weber from the intake manifold with the phenolic spacer, I lose low end torgue but increase the top end. Is this the case? and if so- are there any limitations other than top of carb clearance on the height of the spacer? :cool:
 

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I have never had a phenolic spacer on my Weber 32/36. I have great torgue on the low end but my top end sucks. If I understand correctly from Ralley Bob's postings, by increasing the height of the Weber from the intake manifold with the phenolic spacer, I lose low end torgue but increase the top end. Is this the case? and if so- are there any limitations other than top of carb clearance on the height of the spacer? :cool:

I've done back-to-back testing and saw a significant difference from changing spacer heights. A 1/2" change in spacer height (reduction) lost me 9 mph of top speed in one of my cars, but the acceleration improved drastically in-town.

The real problem is that a GT chassis won't tolerate much of a spacer, and that also depends on the specific intake you have... they vary from the factory in height by almost 3/8" depending on the year.

A few things to consider are:
*Hood clearance
*Length of the intake manifold studs
*Throttle linkage alignment...very critical!


Bob
 

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I've done back-to-back testing and saw a significant difference from changing spacer heights. A 1/2" change in spacer height (reduction) lost me 9 mph of top speed in one of my cars, but the acceleration improved drastically in-town.

The real problem is that a GT chassis won't tolerate much of a spacer, and that also depends on the specific intake you have... they vary from the factory in height by almost 3/8" depending on the year.

A few things to consider are:
*Hood clearance
*Length of the intake manifold studs
*Throttle linkage alignment...very critical!


Bob
Oh boy is this a can of worms
Hood clearance is a Big problem repeat a big problem
I can't for now get enough air into the carb on the GT even after tring four different setups.
 

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Opeler
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you could make an air box that is shaped to the hood. Then make a tube, say 3" round opening and then put a cone filter on that.
Good idea. You could make a teardrop-shaped plate that screws to the top of the Weber, a little larger than the outline of the hood bubble. Some foam weather strip would seal it to the hood, and then it could be ducted to the stock air cleaner.

The only problems I can think of are that the float bowl might interfere with the duct location, and you would have to to make sure to get a good seal around the hood taking engine movement into account.
 

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Weber Carburetor Guru
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I didnt really mean to seal that against the hood. I think if you make something like the factory housing but make it fit the Weber, and then have a housing that sort of looks like this



and put a cone on the end. This might be too big for the Opel. But you get the idea
 
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