Idle speed adjustment

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Jim Beam
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Idle speed adjustment

#1 Post by Jim Beam » Mon Jun 11, 2018 3:01 pm

1963 B normal running Weber 40s and 050 distributor.I would like to increase idle speed to around 700 rpm. Searched but can't find any articles/directions to accomplish idle speed adjustment. Help appreciated.

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David Jones
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Re: Idle speed adjustment

#2 Post by David Jones » Mon Jun 11, 2018 4:07 pm

Jim,ideally you should use a synchrometer when doing this adjustment because otherwise the carbs will not be balanced side to side. Get hold of one of these then with it installed in a velocity stack or across the inlet of one carb throat you can adjust the idle screw down at the throttle butterfly and synchronize the carbs to whatever idle speed you want.
https://www.amazon.com/Carburetor-Synch ... B00SLH03R4
See the attached link to find the idle screw, it is item # 26. also check Amazon for this book.
https://www.amazon.com/Weber-Carburetor ... C8AFXF3ZXW

http://www.carburetion.com/diags/40IDFDiaginfo.asp
If I had known I would live this long I would have pushed the envelope a little harder.
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Doug McDonnell
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Re: Idle speed adjustment

#3 Post by Doug McDonnell » Mon Jun 11, 2018 5:33 pm

While it doesn't specifically deal with Webers https://www.youtube.com/watch?v=Kkzn0ee ... hU&index=4
1965 356C There is never enough time to do it right, but always enough time to do it over.

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neilbardsley
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Re: Idle speed adjustment

#4 Post by neilbardsley » Tue Jun 12, 2018 8:33 am

http://www.356carburetorrescue.com/jackstaggs.html

Here is an article by Jack on tuning. The only thing I don't do is to take our the leads from the dizzy cap (I shocked myself). I prefer to set the flow using the meter David described. What the article doesn't cover is that you can adjust the flow in each barrel in your webers using the air bypass screw. I've found this useful for getting the carb balance before moving onto the mixture.

Additionally since the generator doesn't start working until 800rpm and then maybe not that well at 800rpm. You should consider 900/1000rpm idle. What way you are charging the battery at idle?

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