PDA

View Full Version : Electric or manual choke



john w
01-01-05, 06:33 PM
Hi Lads

What is the usual Edlebrock carb to fit to a 350 the electric or manual choke type, & would a 750CFM work ok with a usual upgrade, preforma heads & inlet.

Cheers
John

adricar2
01-01-05, 06:46 PM
what engine is the carb on, if it was a 351c then 750 would be fine , a 350 chevy with a performer rpm then that would also be ok,

john w
01-01-05, 06:59 PM
Cheers Ad

I am looking to buy a new 750 electric choke unit, & its for a 350 chevy, it should save having a choke cable, is this the norm.

Regards
John

callum
01-01-05, 07:10 PM
It matters not which way you go. You barely need the choke anyway. The manual is marginally cheaper and inherently more reliable but you pays your money.............

gd02 cob
01-01-05, 08:00 PM
Never had trouble starting mine without a choke. It would be interesting to discover just how many are operated with or without chokes fitted/operating.

Nick

wilf
01-01-05, 10:30 PM
John - with the accelerator pumps on these carbs, a choke is rarely needed, and the choke's working gubbins only impede airflow when it is not needed.

I have never been unable to start my engine even in subzero temps, and I stripped all traces of the choke assembly off the carb a long time ago.

If you really have to , get the manual choke version, then you too can strip it off once you get used to your engine and how it starts in the cold. Or of course, you can leave it on!

Your choice of course.

plod
01-01-05, 10:36 PM
Mine has a manual but pls dont ask what set up it is with as far as anything els is concerned.
makes my life a lot easier. I think it would still work without one but it would be an effort.


Paul

David Large
02-01-05, 06:47 AM
I have just started running my new carb (Weber 500) with no choke. Starting the engine is fine, it is keeping it running while I reverse out of the drive etc that is the irritation. I was thinking of putting a manual choke on it to prevent the engine cutting out in a potentially dangerous situation.

David Large

osgood
03-01-05, 04:46 PM
John, you don't need either really but as someone has already said it does help when cold to have a method of increasing the idle speed until the engine warms up :) Osgood

wilf
03-01-05, 08:29 PM
David - nothing to stop you using a choke cable to activate the fast idle cam without the mixture enrichening parts on the carb.

boyze
03-01-05, 11:09 PM
David , I can give you fast idle without the fuel if thats wot you wan't.

David Large
04-01-05, 07:58 AM
Thanks Dennis, sounds good, shall I see you in the Bell at 7/30 on Thursday evening?
David

osgood
04-01-05, 07:13 PM
David if it makes life easier you can still use the en-richening devise on a Manuel choke: IE the butterfly, but punch three holes in it and the engine wont flood Osgood. ;)

wilf
04-01-05, 07:55 PM
David - just had another thought. If you just need to up the idle rpms temporarily whilst the engine warms a bit, you could do this electrically, using what is known as an "idle-up" kit.

This is available from Edlebrock as a kit, for use on vehicles with air con, that need the idle speed to step up when the air con compressor kicks in. It just uses a small electric solenoid to alter the idle speed (via the mechanical linkage).

Even more trick would be to feed the idle-up solenoid through a normally-closed thermostat - voila! automatic higher-speed idling during warm-up.

Miket
04-01-05, 08:09 PM
Can't see what the problem is, why can't you just put your foot down on the go pedal while it warms up, mine takes about 1 minute till its ready to rock and roll.

mylesdw
04-01-05, 11:18 PM
Mine has a special pedal near the brakes that allows the tickover to be set at any level without even getting out of the car.

I heard one story about Ferraris (the Dino I think it was), that the importers used to disconnect the choke cable as a part of the pre-delivery work because it was far more trouble than it was worth.

snakebite
08-01-05, 11:13 AM
Hi All

On my chevy I run the 770 holly street avenger with the electric choke kit.

I use this without the choke plate to just have the fast idle at cold. When first started this gives me a smooth idle at 1200 revs. :p This allows me to reverse out of my garage and carry out a three point turn straight away, get out of the car to shut and lock the garage door without having to wait or constantly feather the trottle all the time.:thumb: I believe also, due to the the higher revs at start up aids in getting the oil pressure up quicker whilst under no load and also increasing the oil splash up onto the cam.

Certainly works for me :thumb:

Regards

Steve

p.s Happy New Year to all:angel:

osgood
08-01-05, 03:28 PM
[quote:2ff926c26c="snakebite"]Hi All

On my chevy I run the 770 holly street avenger with the electric choke kit.

I use this without the choke plate to just have the fast idle at cold. When first started this gives me a smooth idle at 1200 revs. :p This allows me to reverse out of my garage and carry out a three point turn straight away, get out of the car to shut and lock the garage door without having to wait or constantly feather the trottle all the time.:thumb: I believe also, due to the the higher revs at start up aids in getting the oil pressure up quicker whilst under no load and also increasing the oil splash up onto the cam.

Certainly works for me :thumb:

Regards

Steve Steve you have just given me an idea I have just purchased a 465 Holley four barrel from Real Steel with a divorsed choke (no I diod not know what it was either!). It lookes exactley like the electric unit but works on hot air and before anybody says "much like me really!!" I ripped the lot off and attempted to mind mould my manual choke onto it from a 2300 2 barrell Holley but as usual dont quite hackle so I could put the unit back on without butterfly flap and employ the same method, top man Osgood :angel: :thumb: This site has just told me my message is to short?????! increase it by 10 caractures :confused:

snakebite
09-01-05, 10:23 AM
An added thought!

If you do employ the electric choke for a faster cold tickover without the choke butterfly a point to watch is that on the holly you can do without both the choke butterfly and the cross bar that holds it. Do not! remove the cross bar that operates the cam if you are using a Speed Demon carb! as you can easily have a wide open throttle jam situation. ask me how I know :thumb:. In fact when I was using the holley I removed both and it worked fine, used a Speed Demon and had this problem, went back to the holly and decided that the as the cross bar would not make alot of difference to the air flow, decided to retain it.

Regards

Steve

osgood
09-01-05, 04:41 PM
Steve the speed demon carb is a copy of the Holley, I don't quite get your drift there is no way you can end up with a full throttle situation with the choke idle adjustment on a Holley carb I have just spent the last three months messing about with three different Holley carburetors on my engine I know them arse back-wards :confused: Osgood

Nobby
10-01-05, 12:29 PM
I had the same problem with the Speed Demon. Luckily I noticed that it was possible for the primary to stick open at half throttle if the entire butterfly/crossbar and linkages were removed BEFORE I started the engine.

The fast idle cam has nothing to hold it up if the link wire is removed (the link prevents the cam dropping down too far as it sits beneath it) and it then catches and holds the throttle open. I intend to leave the crossbar linkage in to prevent this happening. Would have bought a Holley if I'd known this!

Nick

snakebite
10-01-05, 08:18 PM
Hi Nick & Osgood

Yes Nick you have hit it spot on!, there is nothing to hold the fast cam in place with the Speed Demon and if you accelerate sharply using a heavy right boot this can happen. I pulled onto a dual carriageway from Mike T's place and had to turn the ignition off under full throttle :mad: . Then crawl home very carefully on no more than 1/8 throttle.

As stated, even though you don't need the crossbar on the holly I have left it on this time. What I also did was to tap a M4 hole into the throttle side of the cross bar and fitted a thread locked bolt and washer to stop any sideway movement of the bar, probably not required but you never know :-( .

If you are using the electic choke type, what you will end up with is a faster tickover especially this time of year when you slow down to a stop after going at some speed, this is because of the cold air passing through the bonnet over the choke bringing it on. To get over this, I made a stanless steel protector mounted off the front carb/maniflod bolt bent and shaped to cover the choke. I do not now have a problem no matter how low the temperature is with bringing on the choke when up to temperature. I will try and upload a photo of this tomorrow.

Cheers

Steve :thumb:

osgood
11-01-05, 07:34 AM
The best action then guys to be on the safe side is to remove the flap only leaving the rod and linkage in place with a lock type star washer on the inside of the trumpet so that the rod cant move out? Eric :)

snakebite
16-01-05, 01:20 PM
Pictures as promised showing electric choke wind shield.

osgood
16-01-05, 02:14 PM
Pictures as promised showing electric choke wind shield.Steve first question what is the purpose of the wind shield, does this make the bio-metal strip act more positively with-in the choke unit?

Having fitted my 465 Holley with divorced choke (hot air) I have removed the butterfly flap only leaving the shaft in place and drilled a hole in end of shaft with clip to keep it in place with all the linkage in place but sadly as I don't have the hot air pipe attached over headers the choke system only half comes off choke, so I have had to remove the throttle adjustment screw (stop) that side as its nearly falling out with tick over @1500 rpm may try and cut the un-threaded part of the stop screw off and see if that helps just to get a high tick over when cold.

Osgood:angel: :rolleyes: :thumb:

snakebite
16-01-05, 04:05 PM
Hi Osgood

As stated previously, when its quite cold, just after I am stonking along the motorway and I pull off and slow down to a standstill i.e roundabout or traffic lights, because you have had a lot of cold air through the bonnet scoop blasting onto the choke housing cooling down the bi-metallic spring, this is partially bringing the choke on. This in turn obviously raises the tickover, in my case because the engine is warm upto 1100 - 1200 revs. This only lasts for a couple of minutes until the bi-mettalic spring warms up again but I found it bloody annoying :angry: . Also, when I first fitted it I left the choke plate on, this in turn richened the carburation. I found that this plate does the trick nicely. I have had no problems since.

In stocks cars of course with no bonnet scoop you would not get this problem.

snakebite
16-01-05, 04:17 PM
Just a quick point with regard to the holly.

If you want to remove the choke horn for better air flow, where the linkage wire is attached to the bi-metalic link. You can hold the plastic cam "up" by fitting a 1BA bolt through this hole. The bolt needs to be long enough approx 1/2 inch