Throttle Dampening

[gofast]

Hi all,

I have an 1HZ motor and was wheeling recently. In low range, I found the throttle over responsive. In other words, just the bumps caused by the terrain, and the shifting vehicle caused my foot to move on the pedal. My 3B handled this well, but the 1HZ is instantly responsive with torque and a harmonic was hard to avoid.

The truck jumped, and jumped until I took my foot on the pedal. It made it difficult to apply any boot when I needed it. I've talked to the local guru and he says this is common on the 12HT, and the turbo version of the 1HZ.

My question: Has anyone experienced this and if so, how did they overcome it? I'm wondering if a spring swap on the throttle might be in order, or is there an adjustment somewhere?

Thanks,

John

 

[Downey]

John, I've never owned a 1HZ, but my experience with Holley and Weber installation kits (particularly linkage arms) has taught us that the longer the arm, the less sensitive the throttle. Is there a location further out on your linkage arm to attach the cable???

 

[roscoFJ73]

You could try fitting some more springs fore and aft on the injector pump or using the hand throttle over the rough bits

 

[Garry]

You could try fitting some more springs fore and aft on the injector pump or using the hand throttle over the rough bits

X2. Worked for me

 

[Dougal]

I've had this on several different vehicles.
For me foot position was the key to beating it.

 

[Tapage]

I've had this on several different vehicles.
For me foot position was the key to beating it.

was my solution for my Tencha ... and actually I like the soft and sensible pedal.

 

[gofast]

So I like the idea of the springs. One of the things I keep forgeting is that my 3B gained accelration by introducing more air -- therefore more mushy.

The 1HZ is different and gains acceleration by adding more fuel. It looks like I'll have to try to find heavier springs for the pump and pedal. Anyone know of a source. I'm also going try ordering new springs from Toyota. I only have 128 on the clock so I doubt they've lost their temper, but you never know and I'll have a spare to take to a spring maker.

Cheers,

John

 

[roscoFJ73]

You can buy new springs for the pedal cheap from Toyota.
My parts shop has a tray kit with various sized small springs and Ive also seen smaller kits of springs for sale in packets.
I wouldnt get springs that are stiffer,rather add some that are pulling the throttle back and some slightly weaker ones pulling the throttle forward and experiment a bit.

 

[sandcruiser]

I don't know, but you might be able to find something interesting at a bike shop... I'm thinking some sort of suspension components designed for mtn bikes. Not so much a full shock, but maybe some sort of little poly donut that will squish a little when you blip the accel pedal. Maybe.

Or maybe springs are an easier/better idea!

 

[Dougal]

I don't know, but you might be able to find something interesting at a bike shop... I'm thinking some sort of suspension components designed for mtn bikes. Not so much a full shock, but maybe some sort of little poly donut that will squish a little when you blip the accel pedal. Maybe.

Or maybe springs are an easier/better idea!

Elastomers (urethane) springs used to be common place on mountainbikes. But they're hard to find now, steel coils and air springs have taken over.
But many bike shops have a small graveyard of old suspension parts, ask for old elastomers and see what you get.

 

[Chrishdj80]

Check out the throttle dampening system on the older Merc G diesel trucks.

They use a small "shock" absorber in the linkage system.

When you plant your foot down, the damper absorbs the punch and delivers a smooth acelerating vehicle.
Also dampens offroad pedal wobble.

 

[whirleybird]

I made a couple of brackets with a small soft damper off a tool box lid. Works a treat off-road. My 12ht 60 (originally 2h) was almost in drivable on bumps before. I removed the pedal spring and it feels about the same