Fast Idle Speed Target

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gzig5

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What's a good target rpm for fast idle? New AVS2 with electric choke just installed. Old carb didn't idle well and had manual choke. Pretty much stock 340 with automatic. It fired up at 2000rpm and I backed it down to 1500 but that still seems high. Will set the hot idle around 750/800 but have to fix a fuel line leak first.
 
Depends what step yur on.
And how much timing yur running.
And standard or automatic trans.
and even ambient temp/elevation.
Some cars, like mine, don't even need a choke.

On second highest step, with stock distributor and timing, Ima thinking 1200 is lots.
With a proper timing curve,and the transfer slot set right, you might be able to run as little as 1000. Really it's your call. If you drive it away right after start up, and you have a 340 TC which are ~2400stall, it won't much matter. But if you let idle for 3 minutes, chances are the idle will have climbed a couple of hundred rpm.And the electric choke heater will have opened the choke valve all the way. You will tap the pedal, and the idle will drop down.
This is the critical moment; will it stay running when you put it into gear?
If it does, great drive away..... if it takes throttle. If it doesn't, this is no longer a choke issue.
If it doesn't stay running, this is no longer a choke issue.
 
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What's a good target rpm for fast idle? New AVS2 with electric choke just installed. Old carb didn't idle well and had manual choke. Pretty much stock 340 with automatic. It fired up at 2000rpm and I backed it down to 1500 but that still seems high. Will set the hot idle around 750/800 but have to fix a fuel line leak first.
1500 is a plenty. set it back to 1200 and see if you like it. I let mine warm up a few min. in the summer..... In the winter I keep it on fast idle longer and it really doesn't need to run 1500 rpm for 15 min anyway.
 
1500 is a plenty. set it back to 1200 and see if you like it. I let mine warm up a few min. in the summer..... In the winter I keep it on fast idle longer and it really doesn't need to run 1500 rpm for 15 min anyway.

That's where I was leaning. It's been so long since I've driven a carburated vehicle I couldn't remember. Just needed that sanity check.
 
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