Weber linkage

[mrmustang]

Originally Posted by bobcowan

Why did you use 2 bell cranks? One double arm, and one triple arm? Couldn't you accomplish the same thing with 1 triple?

Bob,

Gary already answered it, as did Jim just above this response. In order to get everything to work properly, sometimes you have to think out of the box.


Bill S.

[Earl J]

Hello,

I haven’t posted on this forum in a long while, as I do another forum (saac forum). I’ve been lurking in the back ground though. I couldn’t help but to respond to this post. I totally agree with Jim Inglese. Simplicity is best. I went through 3 different linkage set-ups which was costly until I finally settled on what I’ll call version III.

Version I was comprised of a mix of Enderle and Inglese’ bell-crank (see photo) with out-board bell crank over the valve cover. I struggled a bit with the carburetor arms. Each carb had individual adjustments. On top of that the bell crank being over the valve cover. My thoughts were: adjust the valves means to remove the bell crank and re-adjust the carb linkage every time. (uh… no thanks). Butterfly angle in relation to range of motion of the arms seemed to be an issue so…

Version II utilizes the original FIA 289 Cobra/GT-40 center pivot with the so-called corrected butterfly angulations from idle to WOT. Which needed to be mounted on a “turkey pan”/heat shield on bearing bosses, but mine was mounted on heim joints on the existing bosses on the manifold. Mounting on the bosses was a feat all its own which required sectioning and “keying” the center shaft between 2 fixed positions in between the 2 heim joints. But again, utilizing the out-board bell crank and the individual adjustments to each carb, a very complex arrangement. By the way this center bar linkage was sourced from Jay Cushman of Cushman Competition who duplicated this from original GT40 blueprints is what I was told.

Side Note: there are at least 3 different Weber manifolds for the small block Ford. The Cobra FIA, the E&F manifold, the Offenhouser castings, Fords C6FE and C6AE. Then there are the ones from Inglese and Blue Thunder as well as the Chinese junk. Okay more than 3.

Version III is of my own doing, well actually I copied a friend’s 1966 GT350. I saw he ran his linkage up the middle as well as having the bell crank on one of the cast in bosses.
I built mine based on his concept. The bell crank is a universal “Mr Gasket” kit cut down to a 2:1 ratio mounted on an adjustable chunk of steel, keyed onto the front boss. I even stamped a “V” pointer on the adjuster then scribed a line on the #2 runner and marked it with red paint (you can see it in the photo) so IF my adjuster block moved out of position due to vibration I could tell.
The arms on the carbs are from Comp Cams/Inglese. The ganging hardware from front carb to back carb are from Comp Cams/Inglese as well. Heims and little adjuster shafts are previously mentioned Enderle pieces.
The only true custom piece on the set-up other than the adjuster block for the bell crank is the arm on the carb for cylinder #1/2. That arm is comprised of an arm from Comp cams/Inglese tig welded to an off-set arm from Cushman. The Center bell crank pushes this arm and the upper half actuates the cross bar to the other bank (5,6,7 &8) bank. Front to rear are ganged so the throttle shafts are on the same plane. Best of all. It has only 1 master idle screw on the #1/2 carb. All other carbs do not have an idle screw. The main throttle shaft runs up the middle. I just re-bent the accelerator pedal arm to align to the throttle shaft (Mustang/Shelby GT350 applications).

No issues removing valve covers. The system is clean and very simple. I removed the #7/8 carb so you can see the linkage.

I was actually on this forum reading Weber jetting posts

Cheers,
~Earl J

[Earl J]

I wasn’t sure if the previous post would accommodate all the photos so here are the others.

Cheers,
~Earl J

[Earl J]

post deleted..redundant info