Holley 4160 Return Spring

[kramttocs]

The 4160 (a Quickfuel variant) on my 460 isn't returning to the correct idle by itself.
When I first start it up it's usually ok but after warming up, it requires me to either quickly hit and release the pedal (doesn't always work) or put my foot under the pedal and pull up a bit.

Normally I wouldn't overthink this and just throw a spring in a hole on the bottom of the throttle lever (since the linkage connects at the top) hook back to the throttle/cruise control bracket but I was reading something about having two springs - 1 push/1 pull - causing uneven wear.
The return spring hole here is what I am talking about:


I see there is also a bracket/arm that comes out towards the front and appears to bolt onto the throttle lever with the throttle ball.


Or I could add a spacer in the throttle cable spring?

Thoughts?

[85lebaront2]

Most likely the problem is the replacement carburetor throttle levers are French (Chevrolet) style and the ball sits further forward than a Ford throttle ball. This means the return spring on the cable is pretty much at full extension to reach idle. Since Ford does not provide a cable adjustment, there are two main options, modify the bracket to sit in a more forward position or add a spring to the throttle lever. You need to be sure you are getting full travel as the Chevy throttle arm is longer than Ford's so the cable has to move further for full opening.

This is why I hate "universal" carburetors, they are made for Chevy linkage and anyone else is SOL sometimes to get things to work right. Just be glad it's not a Mopar with a throttle rod to the Torqueflite.

[kramttocs]

Thanks Bill. I'd prefer to add the spring over modifying the bracket although slotting it wouldn't be too bad. Wouldn't moving the bracket help the return to idle but harm the wide open position though?

Going the spring route, what are your thoughts on which direction? Pull the bottom toward cab (so attach the spring in a hole opposite the pivot from the throttle cable attach point) or pull the top toward the radiator (spring in same location as the cable attach point)?

[ArdWrknTrk]

A) having the cable attach ball too far from the pivot means you're all the way to the floor, and maybe then some.
This is going to be easier to modulate, but won't feel very precise or 'crisp'

B) I have my spring going forward. Not any fancy chrome bracket, but you can see it in my photo, in the air cleaner thread.
I think I'm attached to the back of my coil bracket.
I drilled a tiny hole in that kicker stop ear at the top front.

[85lebaront2]

On your throttle lever, there are 5 holes in the upper portion, one big one, two small, one real small and a little bit bigger one. If you can use the lowest hole in the throttle lever, that should be about the correct radial distance out for the Ford cable, problem is the too far forward (Ford's throttle lever sits at almost 90° degrees at closed throttle). I would do as Jim suggested and run the spring forward from the lever.

If you take a small piece of flat bar and use it as an extension on the bottom of the cable bracket to move it forward enough to get things in the correct orientation.

[kramttocs]

Thanks guys!
Will rig up something for the forward pull spring.

Bill - so I need to move my ball connector down and to the right?

[Rembrant]

kramttocs wrote

I see there is also a bracket/arm that comes out towards the front and appears to bolt onto the throttle lever with the throttle ball.

I have one of these kits installed on my 4160. It came with 2 springs, but I only installed one.

[Rembrant]

I was trying to find a better picture of where I have it attached...had to zoom in here...in case it is any help.

[kramttocs]

Great photos and a really nice bay!
Just ordered one of them. Hoping it won't hit the coil but for $10 worth a shot.
Also moved the ball down. Even that seemed to add a bit more snap.

Any reason for just using the one spring?

[85lebaront2]

Yes, I can't swear it will completely solve the issue, but it should help.

[Rembrant]

kramttocs wrote

Great photos and a really nice bay!
Just ordered one of them. Hoping it won't hit the coil but for $10 worth a shot.
Also moved the ball down. Even that seemed to add a bit more snap.

Any reason for just using the one spring?

That was when I was installing the engine...it's not quite that clean anymore, but it still looks OK from a few feet back...lol.

One spring seemed like it was more than enough pull for me, so I just didn't bother with the second.

[ArdWrknTrk]

I don't like a heavy pedal

[Rembrant]

ArdWrknTrk wrote

I don't like a heavy pedal

Ya, and I thought mine was heavy enough with the one spring.

[85lebaront2]

Heavy spring, a friend found out the hard way that these needed a heavy spring. With both secondaries open, let off the gas and count 1  2  3 and then it would close. The Holley vacuum secondaries had enough strength at WOT to over power the normal Mustang return spring through the mechanical closing links. Once I installed a stronger spring there was no more problem. FYI, that is two Holley 4160 series 465 cfm carbs for a total of 930 cfm on a .030 over Cobra 289 engine. Picture courtesy of the current owner.

[ArdWrknTrk]

I love that air cleaner, Bill!

Holman-Moody make an attractive repo in a few configurations

[Gary Lewis]

You love that black/aluminum look.  

But you are right, it is a good look.

[kramttocs]

I've only  driven it once but I thinking moving it solved the issue. Thanks!
The return spring kit came in but will hold off to see if something changes and it is needed.

[85lebaront2]

Sounds great! I always made sure when I or any of my mechanics installed an aftermarket carburetor to make sure it got full throttle and would return to idle with no problems.