I just bought a 4780S 800 dp holley and I noticed that holley offers an electric choke kit for it. Has anyone installed one of these and how well does it work? I've used manual chokes before but I don't won't the look of the cable in the car. What do you guys usually do with manual chokes on your double pumpers? I know a lot of you guys have race carbs that don't even have chokes. I could not find a carb with electric choke and mechanical secondaries.

TC,
By looking at your location, I doubt that it gets cold enough to even need a choke on a Holley carb. I have never had one with a choke (at least not one that wasn't locked open) They usually are rich enough at idle that all it takes is a little "playing" with the throttle for a minute or two and they run fine, even in the coldest weather.

Just my opinion,

Holley electric chokes are horrible. They start a cold engine fine but tend to come on when you don't need them and shut off too soon when you do. I couldn't switch mine to a manual fast enough. It's easy enough to hide the cable under the dash if you don't like the look.

Tom

TC,I have both a 750 and a 800 d.p. on my 2 bbc's cars w/ holley's elec.choke and they work fine for me.The key is knowing how to set them up.Once I install them,I loosen the three screws at the choke cap and turn the cap clockwise until the throttle blade just starts to open and retighten the screws.That way the elec. controlled coil spring inside the choke cap is not to tight and putting to much tention on the blade choking the motor out.I also put a on-off 12volt switch under the dash so I can control the duration of it's use (cold Temps)or no use at all (warm temps)where I live.This works great for me!

I just bought a 4780S 800 dp holley and I noticed that holley offers an electric choke kit for it. Has anyone installed one of these and how well does it work? I've used manual chokes before but I don't won't the look of the cable in the car. What do you guys usually do with manual chokes on your double pumpers? I know a lot of you guys have race carbs that don't even have chokes. I could not find a carb with electric choke and mechanical secondaries.

Barry Grant also offers an electric choke for its speed demon, road demon carbs. Not sure of the differences between that and a holley(as far as quality goes), but the demon carbs are based on a Holley platform....my 750 mechanical has an electric choke on it. Good idea to put a switch in for it, I think I'll use a relay though for switching.

Holley electric chokes are horrible. They start a cold engine fine but tend to come on when you don't need them and shut off too soon when you do. I couldn't switch mine to a manual fast enough. It's easy enough to hide the cable under the dash if you don't like the look.

Tom
Holley electric chokes work fine except I've never seen one where the pulloff piston was adjusted properly from the factory. AND--if you buy the choke conversion kit--Holley does NOT include instructions for adjusting the pulloff piston. There's only one thing worse...

Barry Grant also offers an electric choke for its speed demon, road demon carbs. Not sure of the differences between that and a holley(as far as quality goes), but the demon carbs are based on a Holley platform....my 750 mechanical has an electric choke on it. Good idea to put a switch in for it, I think I'll use a relay though for switching.
...and that'd be the Demon version, which DOES NOT HAVE A PULLOFF at all. What were they thinking? That a couple of slots cut in the choke blade is a suitable substitute for a pulloff?


The key is knowing how to set them up.
So, so true.

Once I install them,I loosen the three screws at the choke cap and turn the cap clockwise until the throttle blade just starts to open and retighten the screws.That way the elec. controlled coil spring inside the choke cap is not to tight and putting to much tention on the blade choking the motor out.I also put a on-off 12volt switch under the dash so I can control the duration of it's use (cold Temps)or no use at all (warm temps)where I live.This works great for me!
Well, it works for you, but only because you're willing to turn it into a manual choke that just happens to use electricity. It isn't right; and it's easily fixed to BE right.



Install the electric choke according to instructions packaged with it; use the kit for internal vacuum or external vacuum as needed. For example, a 3310 uses a vacuum port cast into the side of the carb right by where the choke housing goes, and sealed to the choke housing with the cheapest, silliest, tiniest square gasket imaginable. This gasket is EASILY lost or pushed out-of-position when installing the choke housing, by the way. (Internal vacuum--no vacuum hose); while my 850 uses a vacuum nipple on the front of the carb connected to a vacuum nipple on the choke housing with the silliest, big-on-one-end, small-on-the-other end vacuum hose. (External vacuum) The choke coil will be set at the Index mark to begin with--but don't install it until you've got the pulloff piston adjustment done. When you do install the coil, be sure you have a good ground connection.

1. Adjust the pulloff using the "special tool" (a paper clip with the end folded over.) Proper adjustment will have the engine running smoothly when first started--not lean stalling, not gargling on gasoline.
2. Verify that the choke blade is syncronized to the fast idle cam--when the pulloff opens the choke, the fast idle cam should drop to the second highest step, no more no less. If you re-adjust the pulloff, you may have to re-adjust the choke-to-fast idle cam syncronization.
3. Route electrical power through an oil-pressure switch so that the choke coil doesn't heat if the engine stalls.
4. Adjust the choke coil so the choke OPENS at a rate suitable for your engine. The engine should run smoothly after the engine has warmed up "some" (i.e., don't screw with the choke coil because the engine runs bad when first started!) and be fully open at a reasonable temperature. DO NOT (!!!) try to adjust the choke coil so the choke CLOSES in a manner that makes you happy.
5. When the throttle is WFO, the choke blade should be popped open a little more than what the choke pulloff would open it. This is called the "Unloader" and it helps to clear a flooded engine.

Of course, you will want the curb idle and fast idle speeds to be reasonable; and the idle mixture screws must be properly adjusted also. No vacuum leaks--you get the idea--the engine should be in good running condition.

EVERYTHING that you guys are complaining about is FIXABLE by adjusting the RIGHT THING.

The most common mistake is dicking with the choke coil tension adjustment when you "should" be adjusting the PULLOFF PISTON linkage. The choke almost always gets adjusted too lean that way.

PROPERLY adjusted, the choke blade will SNAP SHUT LIKE AN ALLIGATOR MUNCHING FROZEN CHICKEN. But since the pulloff piston pops the blade open that little bit as soon as the engine starts--the engine doesn't gargle! There is NO need for under-dash manual-choke-cables or manually operated electrical switches.



IF (big IF) you still have problems, (you probably won't) there is a temp-sensitive voltage-regulating device that can be installed on the intake manifold:
http://store.summitracing.com/partdetail.asp?autofilter=1&part=HLY-45-267&N=700+0&autoview=sku

Oh, yeah. It is a FRIGGIN' NIGHTMARE trying to find the instructions to adjust the Holley pulloff piston. The instructions are cleverly hidden on the Holley web site; they are NOT supplied with an electric-choke carburetor or the electric choke conversion kits--which is about as stupid as it gets.

You're looking for Figure 15 on this .pdf document. It's on Page 4.
http://holley.com/data/Products/Technical/199R8339.pdf
Grab a paper clip, and adjust as needed to assure engine runs good--no lean stalling, no gargling--IMMEDIATELY after starting a cold engine. It'll likely be about 1/4 inch gap between top of choke blade and air horn--but--more or less is OK as long as the ENGINE RUNS RIGHT when FIRST STARTED. There are several spec sheets on the Holley web site; this one works for many "performance" carbs:
http://holley.com/data/Products/Technical/199R8179-1.pdf
As you can see, the pulloff piston can be adjusted from .080 to more than .400 depending on carb; but "about 1/4 inch" (.250) works pretty well as a baseline.

Once you get the pulloff adjusted, you MAY have to adjust (bend) the linkage from the choke blade to the fast idle cam to assure it drops to the second-highest step of the cam.

One of the hardest things to compensate for is the fact that the choke cools off much faster than the engine, so it may be closed sooner than needed.
Mopar has a similar temperature sensitive device that they use on their electric chokes, basically it's a ballast resistor and a temperature switch that closes about 170° and it's bolted to the intake. When the engine is cold, the current to the choke is limited by the ballast resistor and it opens more slowly, and if the engine temperature is above 170°, it opens much faster. Seeing that the Holley part costs $43, my little junkyard Mopar switches are looking real good.

Schurkey,

Again, excellent posts from you with valuable info. I for one appreciate it. I did not know about this adjustment. So, for me to get the choke worked out, I always just ended up adjusting the rod linkage to have the correct amount of opening, and it seems that I ended up with the screw on the second step. I adjusted the rpms to where I needed at, 1800 to start out. I actually did this to a spare 850vs that I am using before a new carb comes. It has worked, but obviously it was a crutch as compared to the right way.

Shurk,

I see some of the chokes have a small slotted screw that you can adjust...its at the bottom of the pull-off bore. Sometimes they are welched over. What's it do?

Schurkey,

Again, excellent posts from you with valuable info. I for one appreciate it. I did not know about this adjustment.
[Elvis Voice:] Thankyew, thankyew verra much...

Shurk,

I see some of the chokes have a small slotted screw that you can adjust...its at the bottom of the pull-off bore. Sometimes they are welched over. What's it do?
I don't know. Got a photo? Sounds interesting.

My guess is that this screw is an external adjustment for the piston pull off...adjusts the amount of vacuum???

http://i134.photobucket.com/albums/q116/VGIORDANO_2007/IMG_0741.jpg?t=1231120265 (javascript:void(0);)


http://i134.photobucket.com/albums/q116/VGIORDANO_2007/IMG_0738.jpg

One of the hardest things to compensate for is the fact that the choke cools off much faster than the engine, so it may be closed sooner than needed.


This is the biggest problem with the electric chokes. You can be out driving around and stop for a few minutes and the choke will cool off but not the engine. Then when you start it up you are on fast idle until the thing heats up again, a real PIA at cruises. The only solution is to keep adjusting the choke for the different seasons or switch to a manual choke. I chose the later.

Tom

I'm not sure,but looking at the 2nd pic it looks to ajust the depth the pulloff piston travels.The pic also does not show the bendable tang to ajust the throttle blade.I'm thinking this screw turned clockwise keeps the pulloff piston from traveling deeper keeping the blade from closing all the way.A good starting point is the throttle open 1/4"from completly closed before starting a cold engine.Cold starting idle at (around)1300-1400 RPM'S.After starting and engine idleing,tapping the throttle should step-down to the next level on the fast idle cam.

Curious why you think the slots aren't suitable instead of a pulloff Schurkey? Heat dissipation on the choke vs. constant airflow? Very interested in your thoughts. I didn't even know a Holley choke had a pulloff...never owned one.

This is the biggest problem with the electric chokes. You can be out driving around and stop for a few minutes and the choke will cool off but not the engine. Then when you start it up you are on fast idle until the thing heats up again, a real PIA at cruises. The only solution is to keep adjusting the choke for the different seasons or switch to a manual choke. I chose the later.

Tom

I have never had that problem. ??? If you have to adjust the choke, it is only 3 screws. ?? You can even mark where you set it for summer or winter if needed.

I'm not sure,but looking at the 2nd pic it looks to ajust the depth the pulloff piston travels.
Maybe. I'm just not sure. I need to look at one in my hands. I'm kind of thinking that's an access hole for drilling a vacuum passage between the cylinder the pulloff piston rides in, and the vacuum nipple that the hose attaches to. Perhaps the screw head that's visible is just a threaded vacuum plug and maybe doesn't "adjust" so much as it "seals".

The pic also does not show the bendable tang to ajust the throttle blade.
By "throttle blade" I'm sure you mean choke blade. And that's true, not all chokes are set up exactly like the one in the .pdf. I had to bend the linkage rod on mine rather than bending the arm inside the choke housing as shown in the illustration in the .pdf document I linked to.

Curious why you think the slots aren't suitable instead of a pulloff Schurkey? Heat dissipation on the choke vs. constant airflow? Very interested in your thoughts. I didn't even know a Holley choke had a pulloff...never owned one.
Not a matter of heat dissapation, rather a matter of vacuum.

Ideally, the choke blade is fully shut when starting "cold"; cranking vacuum pulls on the fuel passages and really richens the mixture. As soon as the engine starts the choke blade is opened enough to allow air in, reducing the choke effect.

With slots cut in the choke blade, you lose some of the vacuum pulling on the fuel; the cranking mixture won't be as rich. And unless you're willing to weld material to, or grind material from the choke blade--it's non-adjustable.

I have seen Holley carbs for truck use (they had governors on them) that have spring-loaded poppet valves in the choke blade; the blade fully shuts and the springs resist opening at low (cranking) vacuum; but as soon as the engine starts the springs allow the small valves to open and allow air entry. That was a lot of years ago; sorry, I don't have photos. I'm thinking they were set up for a cable-operated manual choke.

BACK FROM THE DEAD: Because sometimes a person just needs to say "THANK YOU!". And so, Hat's Off to 69-CHVL!

My guess is that this screw is an external adjustment for the piston pull off...adjusts the amount of vacuum???

http://i134.photobucket.com/albums/q116/VGIORDANO_2007/IMG_0741.jpg?t=1231120265 (javascript:void(0);)


http://i134.photobucket.com/albums/q116/VGIORDANO_2007/IMG_0738.jpg

Maybe. I'm just not sure. I need to look at one in my hands. I'm kind of thinking that's an access hole for drilling a vacuum passage between the cylinder the pulloff piston rides in, and the vacuum nipple that the hose attaches to. Perhaps the screw head that's visible is just a threaded vacuum plug and maybe doesn't "adjust" so much as it "seals".

I just got back from the garage; I pulled a choke housing off and apart; took photos. "8-by-10 color glossy prints with circles and arrows and a paragraph on the back of each one to be used as evidence..."

And YOU ARE CORRECT. The little screw IS an external adjustment for the choke pulloff piston. SOME Holley choke housings use the paper-clip-and-bend-the-internal-linkage method as detailed in that previous link.

Others (like the one you pictured) use a small screw having a tapered point on the end; which matches the bevel machined into the brass piston. As the screw is turned OUT, the piston goes deeper into the hole and the choke blade is pulled open farther. The screw does not adjust the amount of vacuum; it adjusts the maximum travel of the brass piston.

I have NEVER seen this published as a choke pulloff adjustment; no how--no where. I would not have thought of it if you hadn't posted the photos!

Thanks Shurkey. That adjustment feature would definietly help the choke tuning process. Too bad my new carb doesnt have a choke!

Schurkey,
On a slightly different, but related topic, I am going to be switching from an Edelbrock Performer carb to a Street Avenger 670 in the next week or two. It's my first experience with a Holley and I'd like to start off on the right foot. Will these tips and instructions apply to me? The links you posted are for a 4160 series (I think that refers to a carb with a secondary metering plate, right), and the original title of this thread is "Chokes on Holley Double Pumpers", which mine is not. Just trying to gather as much info as I can before I start fiddling with things I shouldn't!
TIA
Tom

Very likely the same thing on the Street Avenger series.

The choke housing I destroyed for photos was from the electric-choke version of the good ol' 3310. The list number escapes me at the moment but it might be 80808. Same as what's pictured above except it doesn't have the vacuum nipple--the SA and other VS carbs use the internal-vacuum version of the choke housing.

Very likely the same thing on the Street Avenger series.

The choke housing I destroyed for photos was from the electric-choke version of the good ol' 3310. The list number escapes me at the moment but it might be 80808. Same as what's pictured above except it doesn't have the vacuum nipple--the SA and other VS carbs use the internal-vacuum version of the choke housing.


The newer 870 Avenger and the ZZ502 850 vac sec carbs use the external vacuum source, see the vacuum nipple on the bottom of the choke housing? I suspect it works better with the bigger carbs maybe?

The newer 870 Avenger and the ZZ502 850 vac sec carbs use the external vacuum source, see the vacuum nipple on the bottom of the choke housing? I suspect it works better with the bigger carbs maybe?
Again, correct. I should have said "some" VS carbs use internal vacuum.

I have the "crate engine" 850 VS on my boat; it does have the external vacuum.

Do the smaller SA carbs use internal vacuum? I was pretty sure they did...

Yeah the smaller ones are internal. The 870 used to be internal, till they changed to external. I could never get the 870 choke to work right, but that's before you posted all this info. The 850 80531 850 carb choke seemed to work better out of the box. Did you 850 choke work pretty good Shurkey?

No, not without adjusting it. Had the usual gargling-on-gasoline issues. I'll have to go back and re-do it now that I know the better way...

'Course, it's on a boat, so it never sees anything colder than about 60 degrees; and usually 80 or more.

Mostly I use it for the fast idle. I drain the engine water jackets after I put it back on the trailer. The boat has no thermostat (marine positive-displacement water pump) so I need to spin the water pump to get it to prime and then fill the engine water jackets; and the fast idle speeds up the warm-up as well since there's no heat riser valve.

Once I leave the dock, the choke's off and the idle speed is much reduced.

The 850/870 carbs have a different choke plate and different choke tower, wonder if the balance or whatever is off with these carbs, b/c all the otehr chokes worked great for me w/little to no tinkering.

I'm new to all of this - purchased a 1971 chevelle heavy chevy and had someone take off the manual choke and install an electric choke. Problem is, he never finished the job and the lead is hanging. I've never worked on a car before, so was wondering if someone could walk me through hooking up the lead - not sure if I should tap into the ignition wiring? Greatly appreciate someone's help.

Erica

There is a good spot on the wiper motor harness.

FWIW, best to start your own thread on this type of stuff in the electrical forum rather than piggybacking someone else's thread.

..............BACK FROM THE DEAD: ........"8-by-10 color glossy prints with circles and arrows and a paragraph on the back of each one to be used as evidence..."




Alice's Restaurant, 30 years later, Arlo Guthrie. Just listened to it a month or 2 ago or I'd have missed that.


hmmmm, Seasonally Frozen Wastelands......


Singing "You Can Get Anything You Want At Alice's Restaurant" didn't work for you Shurkey? :) JK

Alice's Restaurant, 30 years later, Arlo Guthrie. Just listened to it a month or 2 ago or I'd have missed that.


hmmmm, Seasonally Frozen Wastelands......


Singing "You Can Get Anything You Want At Alice's Restaurant" didn't work for you Shurkey? :) JK
I'm just sittin' here on the Group W bench...


Actually, I like The Motorcycle Song (Story of the Pickle) even more; but "Alice's Restaurant" got all the air time and the movie publicity.

THANK YOU for noticing. I had given up on anyone understanding that joke.

I'm new to all of this - purchased a 1971 chevelle heavy chevy and had someone take off the manual choke and install an electric choke. Problem is, he never finished the job and the lead is hanging. I've never worked on a car before, so was wondering if someone could walk me through hooking up the lead - not sure if I should tap into the ignition wiring? Greatly appreciate someone's help.

Erica

Erica,
Here's where to start...
Do you have a 12-volt test light? That's the easiest way to identify the wire you want to tap into. Connect the ground lead on the test light to a nearby ground (header bolt worked for me) and touch it to the terminals of the wiper motor wires one by one. When you find one that has 12-volts while the car is running, tag it with a piece of tape. Get yourself a package of 3M T-Tap connectors as well as the end terminal that needs to be crimped onto the lead you're talking about. Install the T-Tap onto the wire you identified, plug in the lead, and you're done. Best of all, the lead can be unplugged from the splice connector any time you wish, and the T-Tap can be removed if necessary without damaging the original wire.
http://solutions.3m.com/wps/portal/3M/en_US/Marine/Home/Products/Catalog/?PC_7_RJH9U5230GE3E02LECIE20S4K7_nid=GS3MTHGQSCbeV B2NDGZBTHgl
Hope this helps!
Tom

I'm just sittin' here on the Group W bench...


Actually, I like The Motorcycle Song (Story of the Pickle) even more; but "Alice's Restaurant" got all the air time and the movie publicity.

THANK YOU for noticing. I had given up on anyone understanding that joke.

Group W bench, lmfao

my fave of Arlo's is The Train They Call The City of New Orleans. But in all actuality Willie has a better rendition.

The Motorcycle Song was my buddies and mine's fave for a stint in High School, probably during Sophomorehood when all you want to do is **** up. We just loved the "cle".

Bringing this back from the dead...as now, I'm using a carb with a choke again.

Shurkey, I was playing with this set screw for the choke pull-off. What it appears to do is limit how far the coke will open. To me, this doesnt make sense, b/c if the screw contacts the piston at all, the choke flap will be somewhat closed when it should be completely "open". Seems to be that this is backwards...why would I want the choke flap not pulled all the way open? Unless I'm missing a part from that choke housing???


BACK FROM THE DEAD: Because sometimes a person just needs to say "THANK YOU!". And so, Hat's Off to 69-CHVL!





I just got back from the garage; I pulled a choke housing off and apart; took photos. "8-by-10 color glossy prints with circles and arrows and a paragraph on the back of each one to be used as evidence..."

And YOU ARE CORRECT. The little screw IS an external adjustment for the choke pulloff piston. SOME Holley choke housings use the paper-clip-and-bend-the-internal-linkage method as detailed in that previous link.

Others (like the one you pictured) use a small screw having a tapered point on the end; which matches the bevel machined into the brass piston. As the screw is turned OUT, the piston goes deeper into the hole and the choke blade is pulled open farther. The screw does not adjust the amount of vacuum; it adjusts the maximum travel of the brass piston.

I have NEVER seen this published as a choke pulloff adjustment; no how--no where. I would not have thought of it if you hadn't posted the photos!

Bringing this back from the dead...as now, I'm using a carb with a choke again.

Shurkey, I was playing with this set screw for the choke pull-off. What it appears to do is limit how far the coke will open. To me, this doesnt make sense, b/c if the screw contacts the piston at all, the choke flap will be somewhat closed when it should be completely "open". Seems to be that this is backwards...why would I want the choke flap not pulled all the way open? Unless I'm missing a part from that choke housing???
The set screw adjusts how far the choke opens when powered by the vacuum supplied to the pulloff piston.

It should NOT have anything to do with how far it opens based on the choke coil.

More reading; and some photos:
http://www.chevelles.com/techref/Adjusting_Automatic_Chokes.htm

Not a matter of heat dissapation, rather a matter of vacuum.

Ideally, the choke blade is fully shut when starting "cold"; cranking vacuum pulls on the fuel passages and really richens the mixture. As soon as the engine starts the choke blade is opened enough to allow air in, reducing the choke effect.

With slots cut in the choke blade, you lose some of the vacuum pulling on the fuel; the cranking mixture won't be as rich. And unless you're willing to weld material to, or grind material from the choke blade--it's non-adjustable.

I have seen Holley carbs for truck use (they had governors on them) that have spring-loaded poppet valves in the choke blade; the blade fully shuts and the springs resist opening at low (cranking) vacuum; but as soon as the engine starts the springs allow the small valves to open and allow air entry. That was a lot of years ago; sorry, I don't have photos. I'm thinking they were set up for a cable-operated manual choke.

Sorry I'm quite late getting back to your response, I checked it once or twice after I posted but had forgotten about it since until this thread popped back up. Thanks for the detailed explanation, totally clear now.

As for my Demon 750 mechanical with electric choke, I've had no problems with my choke or starting it with the choke on in spring or summer weather. Winter temps/humidity however has not been tested....soon though. I will let you know how well it works here in WA state on the west side of the mountains(the east side is another story).