dual four throttle linkage issue

[Howard H.]

Bought a reproduction throttle linkage for a 58 270 horse a couple years ago and finally getting around to installing it today. It seems like the rod bolt to the front carb is too short. Can't adjust it enough to allow the rear carb throttle to open much before the front starts to open. I have roughly one half inch or less between bolt head and u shape bracket to front carburetor when closed. Rough measurement is a little under 9 inch total length including the swivel/bracket with almost all threads exposed. does any one know the correct length of the front bolt/rod without the swivel/bracket? Any help greatly appreciated.

[Carl R.]

Re: dual dour throttle linkage issue

Hello Mr. Hiller, I do not have a two dour set up on my car, but I have a picture of one that I took at Carlisle a few years ago. It might show you what you are looking for

[Jim D.]

Re: dual dour throttle linkage issue

Is the linkage bracket for the front carb. installed in the lower hole of the lever like posted above? If it's in the upper hole you'll experience the issue that you are having.

[Howard H.]

Re: dual dour throttle linkage issue

Thanks Carl and Jim; was using the Judging Manual's pics for reference when installing it and I still put in the top hole. Wasn't paying close enough attention I guess. Thanks again; Howard

[Joseph L.]

Re: dual dour throttle linkage issue

Hi Howard
Once you have the front carburetor in the bottom hole, you will set the throttle rod bolt to the front carb so that it it is at wide open throttle when the rear carb is also at wide open throttle. I do not feel the front carb begin to open until I am at 75 mph on the freeway. Most of the time the engine runs only from the rear carb unless you want more. I got 18.5 mpg on a 900 mile drive with 3.36 rear.
Staging the front and rear together is great for racing, but not so good on the street. Do you have any of the early WCFB manuals on setting the linkage?
Joe

[Howard H.]

Re: dual dour throttle linkage issue

Joe; thanks for your info. I don't have those manuals but I should be able to make the adjustments from your directions.
Howard

[Howard H.]

Re: dual dour throttle linkage issue

Thought I would update what I found when I moved the arm to the lower hole. When I tried to adjust linkage as Joe suggested the rod was too short to achieve wide open throttle on the front carb when the rear was wide open. I have an older linkage on another engine so I took the front rod apart on the old and new linkage and measured them. The new rod by itself is 7 and one half inches and the old rod is a bit over 8 inches. put the old rod with the new linkage and everything is good. I am going to look for my receipt but I think it has been two years of so since I bought it from CC. Talked to them earlier about this and they replied with pic that the rod in the kit now is 8 inches. I asked if I could get just the rod but haven't heard back yet.