Author Topic: Throttle Linkage/Cable Help...Ideas??  (Read 515 times)

Offline Countn Carbs

  • Jr. Member
  • **
  • Posts: 80
    • View Profile
  • Your Track: Bandimere Mo-Kan
  • Your Vehicle: 1931 Chevy Roadster
Throttle Linkage/Cable Help...Ideas??
« on: November 19, 2018, 01:03:37 PM »
I'm kinda scratching my head on this and looking for input/ideas on what to do for a throttle pedal and linkage or cable setup.  The 5 carbs will all be tied together (non-progressive) and can open by pulling or pushing depending on setup.  These pictures are the best that I have now and I still don't have my tranny shields and locking dipstick on so it will get tighter.
Plan A:
Mount a pedal on a pedestal off the frame then run a cable by going forward off the pedal, through the mid-plate, around the front of the engine and back around to "push" them open.  Seems like a long way around the barn (literally) and I will need to route the cable around the magneto and various other stuff to get there.
Plan B:
Mount a pedal on a pedestal off the frame then build some type of Z bar across the back of the mid-plate to get to the left side of the mid-plate, go through the mid-plate with a cable to "pull" them open.  I'm not really sure if there will be enough room to do this and honestly have not given this approach much thought.
I'm curious what others have done and would like to have your input on what you would do here.
« Last Edit: November 19, 2018, 01:11:55 PM by Countn Carbs »

Offline Countn Carbs

  • Jr. Member
  • **
  • Posts: 80
    • View Profile
  • Your Track: Bandimere Mo-Kan
  • Your Vehicle: 1931 Chevy Roadster
Re: Throttle Linkage/Cable Help...Ideas??
« Reply #1 on: November 19, 2018, 01:09:20 PM »
One side....

Offline Countn Carbs

  • Jr. Member
  • **
  • Posts: 80
    • View Profile
  • Your Track: Bandimere Mo-Kan
  • Your Vehicle: 1931 Chevy Roadster
Re: Throttle Linkage/Cable Help...Ideas??
« Reply #2 on: November 19, 2018, 01:10:19 PM »
The other side...

Offline fuel749

  • Full Member
  • ***
  • Posts: 128
    • View Profile
    • Dragster Supply
  • Your Track: New England Dragway
  • Your Vehicle: FED/Altered
Re: Throttle Linkage/Cable Help...Ideas??
« Reply #3 on: November 19, 2018, 01:19:55 PM »
I use a pedal with the pivot about a third of the way up the pedal from the bottom and use a Morse cable to pull from the bottom of the pedal.  May need to add a short extension to get the ratio right.

Offline rooman

  • Hero Member
  • *****
  • Posts: 536
    • View Profile
  • Your Best Time: 6.200/222.05 (1/4 mile--NT/F)
Re: Throttle Linkage/Cable Help...Ideas??
« Reply #4 on: November 20, 2018, 04:24:11 AM »
First thing if you go the cable route---don't use an actual "Morse" cable. They are way too stiff and are hard to route for that reason. Get one of the spiral bound units from Control Cables (or the same thing from Good Vibrations who have them in stock).
 As you have plenty of room above the bell housing I would think about a cross shaft deal. Hang the shaft from the top frame rails or on stands off the mid plate and put it far enough back that you can drop an arm on the pedal side and still have room for it to swing forward. You may need to put a bellcrank on the back of the inlet (or somewhere in that general location) to get the linkage high enough to get the pull angle correct for the carbs. This is basically what the blown cars did in the front engine era although they did not have the complication of getting the action to the left side of the motor. Don Long had one bellcrank on the mid plate to get the action vertical and another on the back of the blower to send it forward to the front of the injector. Long also used the small rectangular Moon pedal which has a tab on the back to attach the link that goes forward to the bellcrank on the mid plate.
 One more thing---- looking at your steering box mount I would add some more bracing/gussets somewhere. With the bracket being so long and the rod end support on the sector shaft so close to the box itself there is a chance that under load the box may deflect. I would put a mount on the outside of the top frame tube and drop a 1/4" aluminum plate to run the shaft through. The closer that you can get the support to the pitman arm, the better.

Roo
« Last Edit: November 20, 2018, 04:31:02 AM by rooman »
Yeah, I am from the south--any further south and I would have been a bloody penguin.

Offline THE FRENCHTOWN FLYER

  • Full Member
  • ***
  • Posts: 173
    • View Profile
  • Your Best Time: 8.28@168 door; 9.00@147 6-cyl alt; 8.53@160 RED
  • Your Engine: 300 Ford six NA w/ crossflow and prod. heads
  • Your Track: Milan, Thompson
  • Your Vehicle: Advanced Chassis altered , The Last Logghe altered, '30 RPU
  • General Location: North Coast
Re: Throttle Linkage/Cable Help...Ideas??
« Reply #5 on: November 20, 2018, 08:14:52 AM »
Countin Carbs,
I faced a nearly identical situatrion when restoring my Logghe car (except, being a Ford everything is symmetrically opposite on the engine) and I chose your PLAN B.

I'm sorry I do not have a better pic.
Gas pedal on the right, barely visible behind the red shield mounted off the lower frame rail. You see the mandated throttle return toe loop on the pedal.
Then through a couple of bellhousing mounted bell cranks with Heim jointed links to a short (yellow) cable out the top of the body work just behind the block plate. The yellow cable is actually just a piece of nylon air line with a piece of stainless steel welding wire inside it, threaded on each end for small heim ends. I carry a  spare stainless wire with me but it has never broken. Then to a common intermediate shaft with additional adjustable Heim jointed links for each carb which in my case are sideways mounted.

Whew. When I was done I counted 138 separate pieces needed to make up the linkage. But it works well. Good luck with your project.

« Last Edit: November 20, 2018, 08:16:25 AM by THE FRENCHTOWN FLYER »

Offline Countn Carbs

  • Jr. Member
  • **
  • Posts: 80
    • View Profile
  • Your Track: Bandimere Mo-Kan
  • Your Vehicle: 1931 Chevy Roadster
Re: Throttle Linkage/Cable Help...Ideas??
« Reply #6 on: November 21, 2018, 07:05:20 AM »
Thank You Guys!!  I appreciate the help/ideas and input.  I'll see what i can come up with on getting to the left side of the car before I go through the mid-plate and rethink my steering box setup.

Offline jeff/21

  • Full Member
  • ***
  • Posts: 156
    • View Profile
  • Your Best Time: 8.24
  • Your Track: any with-in a 6hr radius
  • Your Vehicle: fed
Re: Throttle Linkage/Cable Help...Ideas??
« Reply #7 on: November 21, 2018, 04:37:01 PM »
The steering I would add a gusset and move the pitman shaft bearing closer to the arm I used a nylon block on top of the frame but you would have to mount it under or to the outside using something like a pillow block from a go-kart. as for the throttle  I have used cable from a mountain bike they have threaded ends so you can use female rod ends and are very flexible