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> Looking for info on effectiveness, dual carbs on 1.7
nditiz1
post May 30 2023, 06:17 AM
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Possibly acquiring a 1.7 engine and putting dual carbs on it for a friend. Would love to have the FI, but time and parts are against me. Who is effectively running dual 40 webers on a stock 1.7? Not debating which is better to run. If you say runs the same as a stock 2.0 with FI cam then I got my answer. Thanks all!
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Superhawk996
post May 30 2023, 07:00 AM
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Ran 40 IDF’s on my first 1.7L in 87’ with stock cam before rebuild to 1911cc.

Wasn’t terrible with 28mm venturis. Overall, I probably could have went with 26mm vents as it was still mildly over carbureted with 28s. Was much better after the rebuild that included a cam.
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r_towle
post May 30 2023, 08:56 AM
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I would suggest 36 mmcarbs.

It does work, but 40mm are a bit large
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nditiz1
post May 30 2023, 10:27 AM
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Thanks, I should be good to go then.
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63ratster
post May 30 2023, 11:03 AM
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I'm currently running Spanish Weber 40's on my 1.7L with the stock heat exchangers and a Bursch exhaust. We are at the same elevation so I listed my setup below. The Spanish Webers wouldn't pull enough vacuum, so my 1.7 D-jet distributor wasn't happy and it didn't run well. I switched to a 1.8 L-jet distributor because it has a better curve(when not running vacuum) but it's still not perfect. I recommend a 123 Distributor or even the CB Black Box, which I am going to try in July. I hope this helps.

Venturi- 28mm
Main Jet- 115
Main Air Correction - 200
Emulsion Tube - F11
Idle Jet- 50
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nditiz1
post May 30 2023, 12:20 PM
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Thanks @63ratster , looks like the base setup for shipped webers. I'll start there.

I plan to run a pertronix svda if I have a spare or pull it off my beetle.
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r_towle
post May 30 2023, 12:55 PM
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They don’t pull enough vacuum because they are too large.
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63ratster
post May 30 2023, 01:41 PM
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Yes, I agree that they are a bit big for the 1.7L, but I already had this set, so I just wanted to get on the road. I will be bumping it up to a 1911cc with a carb cam in the near future.
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r_towle
post May 30 2023, 02:19 PM
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QUOTE(63ratster @ May 30 2023, 03:41 PM) *

Yes, I agree that they are a bit big for the 1.7L, but I already had this set, so I just wanted to get on the road. I will be bumping it up to a 1911cc with a carb cam in the near future.

Get a t-fitting and pull vacuum from both carbs.
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BK911
post May 30 2023, 03:10 PM
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Empi 40s on a stock 1.7 with 009 dizzy.
No issues and ran awesome.
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nditiz1
post May 30 2023, 03:54 PM
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(IMG:style_emoticons/default/beerchug.gif) this is what I like to hear
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cgnj
post May 30 2023, 04:32 PM
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Empi is making a series D carb Dellortto clone (40 & 45). It has received good reviews on stf. I think DRLA 36 is the ticket depending on price.
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63ratster
post May 30 2023, 09:10 PM
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QUOTE(r_towle @ May 30 2023, 02:19 PM) *

QUOTE(63ratster @ May 30 2023, 03:41 PM) *

Yes, I agree that they are a bit big for the 1.7L, but I already had this set, so I just wanted to get on the road. I will be bumping it up to a 1911cc with a carb cam in the near future.

Get a t-fitting and pull vacuum from both carbs.



I tried the T and the Anti-pulse Valve from Air-cooled.net and the it made no difference. The Spanish Webers will simply not pull enough vacuum. That doesn't mean that the Italian Webers or Empi's will not. I have no experience with those.
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r_towle
post May 30 2023, 09:28 PM
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QUOTE(63ratster @ May 30 2023, 11:10 PM) *

QUOTE(r_towle @ May 30 2023, 02:19 PM) *

QUOTE(63ratster @ May 30 2023, 03:41 PM) *

Yes, I agree that they are a bit big for the 1.7L, but I already had this set, so I just wanted to get on the road. I will be bumping it up to a 1911cc with a carb cam in the near future.

Get a t-fitting and pull vacuum from both carbs.



I tried the T and the Anti-pulse Valve from Air-cooled.net and the it made no difference. The Spanish Webers will simply not pull enough vacuum. That doesn't mean that the Italian Webers or Empi's will not. I have no experience with those.

Start another thread.
Please post a picture of where you are hooking up the vacuum on the carbs.

Rich
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