06-20-2023, 08:06 PM | #1 |
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How to adjust idle
I've driven my truck for about 10 minutes after having a crate engine put in. It's a blueprint 350 carbureted small block. Is near as I can tell I would simply loosen these 2 screws and slide the accelerator cable bracket forward correct?
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1971 C10 manual cab. 76 4x4 chassis. Cut short frame. Carbureted Blueprint 350, automatic 700r4. ~ James |
06-20-2023, 09:28 PM | #2 |
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Re: How to adjust idle
No, that's incorrect.. Leave the bracket alone.. The curb idle is adjusted by turning a screw on the carburetor.. Located on the driver side of the carburetor body, near where the throttle shaft passes through.. The screw is hidden from view of the camera in your pic...
Idle adjustment is made only after the engine is thoroughly warmed up and choke is fully open. Last "item" on the adjustment list.. (1) timing, (2) idle speed, (3) idle mixture, (4) final idle adjustment. |
06-20-2023, 11:31 PM | #3 | |
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Re: How to adjust idle
Quote:
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1971 C10 manual cab. 76 4x4 chassis. Cut short frame. Carbureted Blueprint 350, automatic 700r4. ~ James |
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06-20-2023, 11:34 PM | #4 |
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Re: How to adjust idle
Idle screw location
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06-20-2023, 11:54 PM | #5 |
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Re: How to adjust idle
Oh thanks. I really appreciate that. I'm going to go look up some videos on the steps mentioned also.
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1971 C10 manual cab. 76 4x4 chassis. Cut short frame. Carbureted Blueprint 350, automatic 700r4. ~ James |
06-26-2023, 02:12 PM | #6 |
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Re: How to adjust idle
What Rusty said...After you get the timing close, put a vacuum gauge on the manifold vacuum port. Some carbs have two mixture screws some have four, Count the turns in until lightly seated so you have a reference point. I have mine at one turn out on the Holley 4-corner, 2-1/2 turns out on one of the Quadrajets. Use that vacuum gauge to set your mixture screws, one at a time, making small adjustments on the mixture screw will raise or lower the vacuum. Adjust each screw to max vacuum, making small adjustments to the idle speed screw as you go to hold the recommended idle speed. Also making timing corrections as you go. Those Blueprint motors are broke in and ran before leaving the shop. They have perfected the art of what works and what don't. I havent read one bad review on their motors, they seem to hold together well. What I meant to say is, follow what Blueprint recommended for that motor. "Cheers!"
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Michael of the clan Hill, "Two Seventy Two's" 71 1-ton Dually 350 4-Speed 71 C/50 Grain Truck, 350 Split-Axle 4-Speed 02 3/4 ton Express 14 Indian Chief Vintage 1952 Ford 8N, "Only Ford Allowed On The Property" "Be American, Buy American" |
06-26-2023, 02:48 PM | #7 | |
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Re: How to adjust idle
Quote:
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1971 C10 manual cab. 76 4x4 chassis. Cut short frame. Carbureted Blueprint 350, automatic 700r4. ~ James |
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06-26-2023, 03:02 PM | #8 | |
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Re: How to adjust idle
Quote:
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1971 C10 manual cab. 76 4x4 chassis. Cut short frame. Carbureted Blueprint 350, automatic 700r4. ~ James |
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06-26-2023, 06:04 PM | #9 |
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Re: How to adjust idle
1000 rpm will be fine....just make sure your vac advance is disconnected and plugged when setting you mechanical total timing.
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06-26-2023, 06:37 PM | #10 |
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Re: How to adjust idle
Yup, absolutely, thanks!
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07-02-2023, 01:48 PM | #11 | |
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Re: How to adjust idle
Quote:
If you have an automatic choke, it should be temperature responsive.. When the engine is cold and not running, the choke should be completely closed. "Patting" the throttle pedal before starting allows the choke to close. Upon start up, the choke will open slightly -- 1/4" to 3/16".. As the engine temperature comes up, the choke will slowly move to the fully open position. Curb idle, engine fully warmed up, for a basically stock engine should be about 650 RPM - 750 RPM, depending on transmission type. That 35* timing setting recommended by Blue Print is total advancement. Connect a timing light and with engine running, slowly open the throttle until the timing stops advancing.. That's the rpm to use to set the timing at 35*. This is done with the vacuum advance hose disconnected and plugged. 1,000 rpm will not be fast enough to reach full advance.. |
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07-02-2023, 02:36 PM | #12 | |
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Re: How to adjust idle
Quote:
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1971 C10 manual cab. 76 4x4 chassis. Cut short frame. Carbureted Blueprint 350, automatic 700r4. ~ James Last edited by K10-Kansas; 07-09-2023 at 09:10 AM. Reason: Typo |
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07-02-2023, 02:38 PM | #13 | |
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Re: How to adjust idle
Quote:
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07-03-2023, 11:45 AM | #14 | |
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Re: How to adjust idle
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Typically, you want all the advance in around 2500 - 3,000 RPM.. If the advance is "brought in" too fast or too soon, pre-ignition can occur. |
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07-03-2023, 02:01 PM | #15 | |
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Re: How to adjust idle
Quote:
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1971 C10 manual cab. 76 4x4 chassis. Cut short frame. Carbureted Blueprint 350, automatic 700r4. ~ James |
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07-08-2023, 02:23 AM | #16 |
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Re: How to adjust idle
Im thinking 800 for a nominal pump gas build...And yes find out what their recommended idle rpm for that build is.
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Michael of the clan Hill, "Two Seventy Two's" 71 1-ton Dually 350 4-Speed 71 C/50 Grain Truck, 350 Split-Axle 4-Speed 02 3/4 ton Express 14 Indian Chief Vintage 1952 Ford 8N, "Only Ford Allowed On The Property" "Be American, Buy American" |
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