 Carb Bellcrank Equation |
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| damnfiknow |
 Dec 28 2010, 09:12 PM
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#1
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Member  Group: Members Posts: 77 Joined: 25-October 09 From: Texas Member No.: 10,980 Region Association: None  |
Someone, please, the equation for determining the diameter of a bellcrank to be used on a Weber 40 setup. Standard 914 accelerator cable length/throw (full close/full open) and standard Weber 40 butterfly. Also, anyone know of a source for such a bellcrank? Hope not to have to farbricate one myself. No lathe so will have to be with an electric drill for turning power. Extremely primitive.
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| Cevan |
Dec 29 2010, 03:03 PM
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Senior Member Group: Members Posts: 1,079 Joined: 11-December 06 From: Western Massachusetts Member No.: 7,351 |
Let me see if I can remember how I did mine. If I recall, the sweep of the IDF's butterfly is 78 degrees. I measured mine. Then I measured the amount of cable taken up by the gas pedal (with the adjuster at about the mid-way point). The circumference of a pulley needed to pull the right amount of cable is the length of the cable throw divided by (78/360). The radius of the bellcrank or in my case, the pulley is the circumference divided by 2*pi.
So if the gas pedal took up 2 inches of cable, then the circumference is 2/(78/360)=9.2 inches. The radius of the pulley=9.2/2*pi=1.47 inches. So the diameter would be 2.94 inches.  |
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Posts in this topic
damnfiknow Carb Bellcrank Equation Dec 28 2010, 09:12 PM
McMark The absolute best bellcrank I've seen is this ... Dec 28 2010, 09:17 PM
mrbubblehead
The absolute best bellcrank I've seen is this... Dec 28 2010, 11:15 PM ConeDodger
The absolute best bellcrank I've seen is this... Dec 29 2010, 02:34 PM
anderssj
The absolute best bellcrank I've seen is this... Dec 29 2010, 02:43 PM biosurfer1 I have the one Mark pointed out and I like it. It... Dec 28 2010, 10:01 PM McMark I sure do! Dec 29 2010, 01:10 PM jeffdon
I sure do!
So in this setup, it appears tha... Dec 29 2010, 01:15 PM mrbubblehead
[quote name='McMark' post='1411156' date='Dec 29 ... Dec 29 2010, 02:23 PM SirAndy My carbs are absolutly identical, which means the ... Dec 29 2010, 02:24 PM mrbubblehead
[quote name='McMark' post='1411156' date='Dec 29 ... Dec 29 2010, 02:39 PM mrbubblehead
I sure do!
do you think this is a better se... Dec 29 2010, 01:32 PM kg6dxn
I sure do!
do you think this is a better s... Dec 29 2010, 02:16 PM porschetub
I sure do!
do you think this is a better s... Sep 13 2019, 01:22 AM McMark
I have a hunch that it does not pull equally on b... Dec 29 2010, 03:49 PM azbill Take a look at the Sidewinder bell crank designed ... Dec 29 2010, 05:57 PM 914werke @mcmark In the example pic you provided it appear... Sep 12 2019, 05:21 PM johnhora Source for the CSP Mark mentioned...
https://www2... Sep 12 2019, 09:53 PM porschetub
Source for the CSP Mark mentioned...
https://www... Sep 13 2019, 01:29 AM Tbrown4x4
[quote name='johnhora' post='2746671' date='Sep 1... Sep 13 2019, 03:02 AM Chi-town Type 4 with pancake fan I believe is the applicati... Sep 13 2019, 09:20 AM 914werke I bought Mark's bracket and took the cable up... Sep 13 2019, 09:52 AM euro911 Wow, old thread.
I used the CSP bell crank linkag... Sep 13 2019, 10:54 AM Tbrown4x4
I bought Mark's bracket and took the cable u... Sep 13 2019, 05:28 PM bbrock
@[url=http://www.914world.com/bbs2/index.php?sh... Sep 13 2019, 06:15 PM Tbrown4x4 Yes, 4 inches overall. That left a nice radius fol... Sep 13 2019, 07:53 PM porschetub Currently out of necessity building one from a chi... Sep 13 2019, 11:24 PM porschetub Speedworks (?) have one but its a front mount that... Sep 14 2019, 11:26 PM |
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