I have a 305 that has a pos failing holley carb. This car is not computer controlled anymore. I'm looking for road demon to stick on there but I can only find the ones with a electronic choke. I guess I just dont know what that electronic choke is tied into. Is it tied into a computer or does it run independent and just needs 12v? I would really like to get another carb ordered today cause this holly is spraying gas straight up, I dont care to fix it, I care to take a sledge hammer to it for the problems that its always giving me lol. Anyway... can someone help explain this electronic and manual choke thing?

Thanks

 

So, are you running a choke now? or is wired open? or manual?

An electric choke just needs a 12V while in "Run". It grounds to itself. There is a little bit of tuning involved with an electric choke, but its nothing serious - pretty simple.
To operate it you basicly just put the gas to the floor once, to close the choke and turn on the high idle. Mash the gas again to kick off the high idle and it does the rest. Pretty neat.

BTW, What type of holley do you have?

 

hmm.. so the throttle cable hooks to the electric choke on the side of the carb but when it pulls it back the electric choke module sences how much is being pulled back and then regulates the amount of fuel being released into the fuel bowls right? Whats the benifit? easier to push the gas pedal? More stable fuel flow and responce?

My carb? lol I dont even know. May have been a 650 something or another at one point but right now its got parts from a few different carbs. So many changes, parts, and hack jobs have been done to this carb. Has JB weld blocking some port lol I really couldnt tell you what it is anymore.

 

Well, no, not really... Let me see if I can explain this better:

Basicaly, you have a choke plate thats on top of your carb. When your choke is "on" or "closed" the plate closes(horizontaly) as to block off air (it stays a little open at all times however). When it does this your A/F ratio becomes VERY rich, which is needed to start a cold engine. As your engine warms up the ratio needs to be leaned out. So, the choke plate starts opening, as to allow more air into the carb.

This works this way because inside that black round housing (on the passenger side, your 12V and - hook up here too) there is a coil. Now, we know heat expands and cold contracts. When the engine is cold the coil wants to coil up more and become smaller, thats why when you push the gas pedal before you start the engine it snaps the plate closed (because of the tention of the coil)(the throttle cable and the choke are not directly connected, this works via some simple linkages). When the engine heats up the coil expands and starts pushing the choke plate open again (verticaly).

Now, that IS the basic version, it can get alittle more complicated, but thats how it works.
Got any pictures of this carb? Sounds interesting.

 

Its just a normal old style carb, I'm sure you have seen plenty. Though if it wasnt such a fire hazard I would try to get a vid clip of this thing spraying gas straight up. lol I think I've had enough of its curse.

 

If you'd like to donate your failing carb to the "get Adams car to the track" effort....

 

Haha nice try.

If you want to get rid of it real cheap, let me know? Me and Adam will duke it out then.

 

Haha, sucker... I said first, I got Dibs now!

 

Well, I'm confused reading through this, so I wouldn't be surprised if you're still confused.

The choke is "electric", not "electronic". As stated, you need to provide it 12 volts that is only on when the ignition is on. There is a thermostat coil in the "electric" choke that is heated by the electrical power to operate the choke in a consistent manner - trying to warm the thermostat with engine heat only is inconsistent and troublesome. Most aftermarket electric chokes have 2 terminals, one which gets the 12 volt power, and the other that needs to go to a ground. I believe the Demon chokes are that way as well, if it only has one terminal then all you need to do is hook up the ignition-switched 12 volts.