Throttle return and kickdown springs

Hi everyone

225 1920 Holley 1-barrel carb.

What's the deal with these springs ? I need both circled in blue below (both are missing) but I can't find any info on specs or actually anyone selling them (Mancini/ebay etc) - no-one seems to care about the /6 when it comes to return springs.

So, some peeps have simply applied whatever springs are lying around or what they can find in Home Depot so I'm wondering if this is the go here or if I need to be a little more scientific.

I can go and check out my Home Depot equivalent plus other retailers down here in Aussie of course and/or I can get the springs made but for this I need the build specs.

Does anyone know where I can find these springs for sale or can gather some measurements for me on oem springs from your springs ?

Thanks in advance everyone.

Maybe in the correct church
Slant Six Forum - Index page

Thanks @A56 - Figured I'd try here first and if nothing jump over.

One spring is a basic throttle return spring. You can buy these at any auto parts store.
The other is a spring on the trans kickdown linkage. It pulls that slotted link back after you engage the kickdown.

There was also something along the way where they (govt) said that there had to be redundant (dual) return springs.

Thanks for the replies here. I imagine there was/is a spec for these springs (wire gauge, number of loops, spring length etc) but I cannot find one anywhere so can only imagine it's not a big deal as long as the tension is not stupid enough to but strain on any pivots. My 1920 must be a '74 or later as it has the internal throttle return spring and I have read that the external return spring acts as a secondry as @volaredon rightly suggests.

I shall therefore wander down to my auto part store/ebay and see what I can find.

Thanks everyone.

Check the Help bubble packs at your auto parts. I have at least one with assorted "throttle return springs". The transmission kickdown slot spring serves double-duty as backup to the throttle return spring, so since you have another one on the carburetor itself, you are triple-redundant. But that doesn't insure your throttle won't stick open due to a sticky cable. Back in the day, drivers knew how to handle that. If you didn't "floor it" often, the accelerator pedal could stick. I had to sometimes kick it to get it to return in my 1969 Dart and fixed it by cleaning the cable end, fixing the broken plastic dust shield at the end, and a little non-gunk lube (perhaps silicone today). Worst-case, you can always turn off the engine and be ready to muscle the heavy steering wheel as you slow if power steering.

But, today we have people like the CHP employee in San Diego who sped around with a stuck Toyota pedal talking to 911 for 2 minutes before crashing and killing most of the family. Even worse with battery-cars which accelerate surprisingly fast from a stop. Today's accelerator pedals are just a "user request" like a PC mouse, in both battery and gas cars, so not sure that is any safer than a mechanical linkage which can stick, as they can become as erratic as your mouse. Re your "correct spring", good luck finding specs or a PN. Even if you do, are you sure what Chrysler spec'ed is the safest choice? At least your slant won't be throwing you thru any storefronts before you can blink, like the many Tesla cars you can find on the web.

Glad I stumbled upon this thread. Is there suppose to be a significant response between the spring and transmission linkage? My stock spring is a bit worn out I think. To describe it, my automatic transmission (‘74 225 with the 1920) is shifting hard from 1 to 2 at nearly 30mph, revving serious RPMs, then from 2 to 3 at nearly 50mph with the same response. Once I hit 3rd, it immediately wants to hop back to 2nd at nearly 50. Surely my spring isn’t the main cause? Perhaps a linkage issue?

Doubt it's a "spring issue".
Probably a linkage adjustment issue or else something is going on within the trans.
How's the fluid, level and color?

volaredon said:

Doubt it's a "spring issue".
Probably a linkage adjustment issue or else something is going on within the trans.
How's the fluid, level and color?

Click to expand...

Fluid is looking good. I was going to give it a little longer before routine change. Transmission stuff is new territory for me.