[gomowgto]

Can someone tell me what the fast idle setting for a 1967 gto with the 400 and manual transmission. I know it's set with the fast idle cam on the top step, but the book says 2,500 rpm if I'm reading it right, but that seems high to me. I am running a rochester carburetor with a manual choke. As always thanks for your help.

[wbnapier]

I set my fast idle cam to approximately 1500 RPM on a '65 tri-power. 2500 RPM is overkill IMO. The idea is to just warm up the engine and make sure it doesn't stall out on cold starts.

[leeklm]

Also keep in mind the factory had to consider cars being started in below zero weather conditions- something our old cars rarely experience today.

Back in the day, starting a carb engine at -25 would usually require some delicate foot work to keep the engine running for a minute to loosen things up and let the fast idle system take over and do it job!

Sent from my SM-G965U using Tapatalk

[padgett]

"usually require some delicate foot work ". Unless you had a Rochester FI, they started immediately.

[U47]

Originally Posted by padgett

"usually require some delicate foot work ". Unless you had a Rochester FI, they started immediately.

1967 GTO's didn't come with Rochester FI.

[Kenth]

1967 GTO uses a divorced choke from factory.
Set the 2500 rpm´s on high step of fast idle cam with hot engine. Tap the throttle and fast idle cam releases for normal idle rpm´s.
Next morning push the pedal once to set choke closed, start engine, choke pull-off will break choke-blade open aproximately 1/4" at lower edge, tap the pedal once and the fast idle cam will relocate to lower step with reduced rpm´s.
After this choke will gradually open as the engine warms up, and after a couple of minutes the choke will be full open.

My advice is to toss the modified "manual choke" and get the proper parts for a fully functional automatic choke.

FWIW

[TROYBOYONE]

How do you set the fast idle cam so that when it's on the top step it will idle at 1500, as opposed to maybe 2000 ?

[wbnapier]

You have two things.

1) Adjust choke so it is richer, which also moves the "tab" and where the fast idle cam sits.

2) Bend the fast idle cam tab with pliers. See photos.

Usually a combination of the two to get it where you want.

Play around with it while the engine is cold and you will learn how the system works.

[Kenth]

Originally Posted by TROYBOYONE

How do you set the fast idle cam so that when it's on the top step it will idle at 1500, as opposed to maybe 2000 ?

Use the fast idle adjustment screw.

[Kenth]

Originally Posted by wbnapier

You have two things.

1) Adjust choke so it is richer, which also moves the "tab" and where the fast idle cam sits.

2) Bend the fast idle cam tab with pliers. See photos.

Usually a combination of the two to get it where you want.

Play around with it while the engine is cold and you will learn how the system works.

That wont help a Quadrajet.

[TROYBOYONE]

To: wbnapier

See your reply dated 6-17-21

Do I bend the fast idle tab DOWN for a lower fast idle rpm (from 2000 to 1500)

[wbnapier]

Do you have a tri-power or a Q-jet?

If a tri-power, like mine, I believe bend up to lower fast idle, but I'd need to go out to the garage to check.

The other commenter, who said, "...that won't help with a Q-jet..." is right, as my comment was specific to a Rochester 2GC on a tri-power. I spoke up without knowing all the facts!

No worries, look at this video: https://www.youtube.com/watch?v=yX_hCujFQ_I

If your carb is a Q-jet and has that screw under the choke, adjust it cold.

Anyone else?

[TROYBOYONE]

It's a 1965 Tri-Power

[wbnapier]

OK, then yes, it is bend up I think. I am at work, so can't check. With the car cold, are you comfortable adjusting the choke? Identifying the fast idle cam? You can see how it works and bend that piece accordingly.