Questions about my "new" Weber...

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petroscf
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Questions about my "new" Weber...

Post by petroscf »

Now that I have started enjoying my new driving experiences, some "technical" questions arose...:

1)The weber I fitted is the 28/36. My old solex was a 32/32. So, in theory, I should be able to achieve better economy when the first choke(??) works and less economy but more power when the second opens, is this right?

1a) So that means that on top-end of the rev range the 2 carbs are similar (power+economy) as 28+36=32+32=64???
(If I am saying completely nonsence, OK, I allow you to laugh, but please correct me...)

2) With the solex, if I am not completely mistaken, the second choke (??I don't know if this is the right term, forgive me for my technical ignorance) was "opening" at about 3750-4000 rpm (until the top end of the range). So, knowing that, I knew how to drive my car economically : simply by not letting it pass 4000 rpm. Now with the weber, I am searching to understand when the 2nd (and less economical) choke opens ...I think now things are different, and it is not a matter of revs: When I press the accelerator a bit deeper than just "caressing" it (about the 25% of the pedal's route) I feel the pedal getting harder on my foot and the car accelerating faster and stronger... So I assume that the 2nd (36mm) choke of the weber opens at a point of the pedal pressing no matter the engine's revs, is that right??
If yes, then I could set this situation to the more sportier or economical by adjusting the accelerator wire 's length??

Ok, sorry for so much writing here, but someone with technical expertise please help with these questions...


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PeteK
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Re: Questions about my "new" Weber...

Post by PeteK »

The weber is a mechanical secondary, so it will always open up at the same throttle position. The solex is vacuum, so it was engine dependent.

The sum of the diameters is the same, but not the area. The weber should flow more.

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petroscf
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Re: Questions about my "new" Weber...

Post by petroscf »

Yes, you're right, I just did the maths: But still, the difference (if you sum the circle areas) is very small (the weber a bit larger than the solex)
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Re: Questions about my "new" Weber...

Post by petroscf »

ok, after "learning" a bit (and getting used to the car's new power-yes, I am now starting to want some more....) the new weber, here I come again with a technical question:
As I am some weeks before the MOT test, and having not had any service after fitting the weber, I noticed that whenever I press the accelerator pedal a bit harder(so that the 2nd choke opens), the revs don't return to the idling level of ~950rpm as when the car starts, but stay at about 1200 rpm. If I turn the car of and turn it on again, then it idles again fine. No matter for how long do I drive the car, if I don't let the 2nd choke open, then idling stays at it's set by the mechanic (a bit less than 1000rpm). When the 2nd choke opens, ~1200 again...And so on...

Is it a matter of lubricating some part of the carb again?

I have to mention that when I first drove the car, the accelerator wire was sticking most of the times, and when I lubricated the carb at the point where the wire mounts (choke puller?) The sticking problem stopped...
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