Throttle too sensitive

[brengl1942]

Hey, I'm looking for ideas/experience with custom throttle setups specifically for off-road use. The Ford 2.3 in my jeep has a very short throw throttle. I use a factory style cable going to a simple Lokar "Lakester" pedal, and due to the short distance between closed and WOT on the throttle body linkage itself, the pedal is very sensitive with short travel. When I'm bouncing over rocks or rough terrain, the slightest movement of my foot will result in a stab of the throttle and the jeep lurching. It is very difficult to keep it steady or to ease into it. This was particularly evident when I took it to UWE for the first time yesterday. The flattie is not exactly a smooth ride over the rocks out there.

I'm looking for a way to basically dampen the throttle response and lengthen the pedal travel so that it is less sensitive to small movements, and make it easier to drive in general but especially around obstacles or rough terrain. Anyone have experience building custom linkages, or know of a good aftermarket solution?

 

[OnlyOneDR]

Would help to post up a picture of the linkage on the throttle body. If it is a lever-type you could extend it somewhat to make the travel longer for the same axial rotation or if it is a cam-type you could possibly swap it out for a larger diameter to get the same effect.

This is one of the reasons why folks will install a hand throttle in the vehicle on the shifter stalk. My Nissan is not especially "touchy" for the throttle but when you get bouncing the same thing happens. I need to do a hand throttle one of these days.

 

[getstucksome]

Is there a way to cut down the top portion of the pedal assembly and attach the throttle cable to the another hole (maybe with a small sleeve or something?) I think that should reduce the cable travel at the top and make it less responsive.

 

[brengl1942]

Is there a way to cut down the top portion of the pedal assembly and attach the throttle cable to the another hole (maybe with a small sleeve or something?) I think that should reduce the cable travel at the top and make it less responsive.

View attachment 400047

That may be an option, but I think I'd also need to get an aftermarket cable of some sort as I do not think the factory cable would have enough length to compensate for the additional travel.

 

[brengl1942]

@OnlyOneDR photos for reference. I think any modification to the pedal and/or linkage will require a custom cable setup. The factory cable only attaches in one way and has no extra length to play with.

 

[getstucksome]

Could you lengthen the lower portion of the pedal assembly? No need to change the throttle cable that way, just a matter of if you have room.

 

[brengl1942]

Could you lengthen the lower portion of the pedal assembly? No need to change the throttle cable that way, just a matter of if you have room.

Not really, my feet can barely fit between the seat and the pedals as it is, not much leg room in a flat fender and I'm 6'4"

 

[paradisePWoffrd]

@OnlyOneDR photos for reference. I think any modification to the pedal and/or linkage will require a custom cable setup. The factory cable only attaches in one way and has no extra length to play with.

Moving the cable down on the pedal stalk doesnt change the cable travel, but it does change the pedal travel, and ratio. You would have to redrill the hole in the firewall lower, and mount it to a lower hole. Or move the pedal up higher on the firewall, to use a lower hole.

Does the pedal run out of travel at WOT?
Have you tried putting a larger spring on the throttle/pedal? It doesnt help with ratio, but a stiffer spring will make the throttle harder to push, and therefore maybe less twitchy.

 

[Ron]

Moving the cable down on the pedal stalk doesnt change the cable travel, but it does change the pedal travel, and ratio. You would have to redrill the hole in the firewall lower, and mount it to a lower hole. Or move the pedal up higher on the firewall, to use a lower hole.

Does the pedal run out of travel at WOT?
Have you tried putting a larger spring on the throttle/pedal? It doesnt help with ratio, but a stiffer spring will make the throttle harder to push, and therefore maybe less twitchy.

A lot of the lokar hot rod pedals have an adjustable center pivot that would allow him to dial in the swing length. Not sure on his specific one. Cant see enough of it to tell

 

[brengl1942]

The pedal can be 'clocked' with teeth inside the center pivot point to adjust the actual pedal position in relation the floorboard. That doesn't change the travel but does adjust the pedal height. As it stands it reaches WOT just before the pedal hits the floor.

Based on the feedback I'm thinking about 2 modifications:
1) move the cable attachment point lower on the pedal stalk to lengthen the pedal travel (may have to relocate the cable hole in the firewall).
2) fabricate a longer pivot arm on the throttle body itself, which should lengthen the travel distance over the TB's range of motion. I may be able to remove it, cut it off, and weld a longer piece of metal. Then I think I'd just need to drill a hole for the little ball joint where the cable attaches.
My only concern with this is that the cable could end up being too short, but hopefully not.

 

[brengl1942]

FWIW, I would have preferred to keep the original jeep pedal, which attaches to the floorboard, but I couldn't figure a practical way to make it work and fit with the 2.3 engine swap. I figured trying to maintain as close to the original Ford 2.3 setup as possible would make it easier. I've never seen the pedals in a 2.3 Ranger or Mustang that would have had this engine from the factory, but I suspect it must have been set up to allow a longer travel than what I have here.

 

[paradisePWoffrd]

Lengthening the arm, at the TB, will change the throw, and the cable might not have enough travel. Changing the position at the pedal, will not change the amount of cable travel needed, since that is determined by the TB.

 

[brengl1942]

So I did some work on it today and changed the throttle cable connection point. I marked some radiuses at different points and decided to go on the conservative side. I also did not yet cut off the top, in case I wanted to change it back.
It added probably a good inch to the pedal travel and makes a noticeable improvement although I wouldn't say the problem is entirely solved. I may also be able to lengthen the cable travel on the throttle linkage itself, but that will be a slightly more difficult task as it would require modifying the cable's attachment bracket on the engine as well as the linkage arm on the throttle body.

Here is the "before":

During: (ignore Raptor liner overspray)

After: (Don't worry, it's welded from the back too, not just the spot on top)