Holley Idle Stop solenoid.(question)

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72HCODE

"My World is Fire and Blood"
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71 Mach 1.
Does holley make a Idle stop solenoid and or mounting bracket for the solenoid for a 4150 or 4160 type carb?

 
You will likely need holley part numbers: Bracket 20-9, Solenoid 46-74, retaining nut 26-57. Let me know if it works out.

Chuck

 
thanks, i used the holley part numbers and found more i ordered one for a universal and a 4160, i'll see which works better.

 
thanks, i used the holley part numbers and found more i ordered one for a universal and a 4160, i'll see which works better.
Glad I was of some help. Let me know what ends up working the best for your application. As it happens, I spent most of the day calibrating a holley 750 for the new engine. The cam is a bit aggressive so I may need the same parts to get the engine to shut down without "run on". Clean idle doesn't happen until 1200 RPM (ok, the cam is more than a bit aggressive).

Good Luck, Chuck

 
thanks, i used the holley part numbers and found more i ordered one for a universal and a 4160, i'll see which works better.
Glad I was of some help. Let me know what ends up working the best for your application. As it happens, I spent most of the day calibrating a holley 750 for the new engine. The cam is a bit aggressive so I may need the same parts to get the engine to shut down without "run on". Clean idle doesn't happen until 1200 RPM (ok, the cam is more than a bit aggressive).

Good Luck, Chuck
Cam specs?

 
thanks, i used the holley part numbers and found more i ordered one for a universal and a 4160, i'll see which works better.
Glad I was of some help. Let me know what ends up working the best for your application. As it happens, I spent most of the day calibrating a holley 750 for the new engine. The cam is a bit aggressive so I may need the same parts to get the engine to shut down without "run on". Clean idle doesn't happen until 1200 RPM (ok, the cam is more than a bit aggressive).

Good Luck, Chuck
Don't want to hijack the thread but would love to know what cam you are running I have a comp cams XE284h

Here are the specs for my cam I also have to get a high idle. In drive below 800 rpm's it is on the edge of dying out.

Basic Operating RPM Range 2,300-6,500

Intake Duration at 050 inch Lift 240

Exhaust Duration at 050 inch Lift 246

Duration at 050 inch Lift 240 int./246 exh.

Advertised Intake Duration 284

Advertised Exhaust Duration 296

Advertised Duration 284 int./296 exh.

Intake Valve Lift with Factory Rocker Arm Ratio 0.584 in.

Exhaust Valve Lift with Factory Rocker Arm Ratio 0.588 in.

Valve Lift with Factory Rocker Arm Ratio 0.584 int./0.588 exh.

Lobe Separation (degrees) 110

 
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Just to get back on topic:

I'm finding that the Idle stop Solenoid may not work the way i think it does on the early pre 1980s cars.

if somebody knows the proper way this solenoid works let me know.

I'm finding the connection is energized 12 volts all the time, i found a description that states the solenoid was just to prevent coming off of WOT to Idle fast and prevent a stall out. it would ease the throttle back down into idle for the last few millimeters of travel. It does not state that the solenoid was used to increase the Idle RPMS 100-200 when the A/C was turned out. I went through the wire diagrams for the 1972 cars with A/C and neither system is tied together(the idle stop solenoid nor the A/C system) i found a reference in one book stating the idle solenoid was tied into the temperature control sensor, but the 71-73 cars only have one that is part of the A/C system to prevent the compressor from icing up the system.

since the original 71-73 carbs used a heat riser for the choke it seems weird that ford would install an electric solenoid just to ease the throttle down, why didn't they use the mechanical kind like on the early cars called a Dashpot and simply save the money in the manufacture of the engine harness? i just don't get the logic.

from what I've read the Holley Solenoid is not a good solution, apparently the holley version is a true Idle up solenoid that will lock into a higher position when 12 volts is applied.

if that is the case then restoring the original function of the idle stop solenoid is a bad idea and i would be better off installing a Dashpot, and using the original connection for my electric choke. obviously this is a waste of time also since i have a Automatic transmission and Dashpots were only needed on manual cars.

I'm hoping somebody can answer if the original idle stop solenoid was electrically on all the time regardless of A/C compressor status.

The ford manuals are no help at all only the engine manual briefly talks about them and how to adjust them, but not anything about the function or testing them. The electrical manual doesn't even cover them at all they are never mentioned in the A/C section.

Based on my reading i conclude the original 71-73 cars never had an Idle up system for A/C cars, i hope somebody can chime in about it.

I believe i will put everything back the way i had it which was working and i'll just bump up my idle rpms a little for some security.

 
Here is what I know for sure. The 1969 Boss 302s had the solenoid to obtain the higher idle speed (required by the heads and cam duration) and allow the engine to shut down without run on. The solenoid was energized when the ignition was ON and de-energized when ignition was OFF. The 1971 manual, page 24-21-11, lists two 4300 carbs with a solenoid (D1OF-EA AND D1OF-AAA tag numbers). According to www.mustangtek.com these carbs were for 1971 351C 4v, auto and manual trans. One picture there shows what seems to be the remnants of a bracket to mount the solenoid. On page 24-23-11 it lists a solenoid used on 429 SCJ with automatic. The adjustment procedure is on page 24-23-03. Here what I think I know. The solenoid had nothing to do with the AC being on or off. It was to ensure a clean shut down with no run on. I hope this helps some.

Chuck

 
I've read about similar function in a few books as well. that would mean the solenoid was energized at all times while the engine was running, and when ignition turned off the solenoid de-energized and the idle was allowed to go down further to prevent dieseling.

If this is the case for the 71-73 then it makes sense as well. it would also not be needed when replacing the original carb with an aftermarket in most cases.

I have read about people splicing the connector for the A/C clutch and using the clutch signal to use a true idle up solenoid, I'm not willing to do this. the first problem with this method is the clutch will cycle on and off and throw the idle up and down. It would be better to splice into the switch that is part of the climate control system inside the car, which would bypass the temperature sensor and keep the idle up solenoid energized only when the A/C system was turned on. that way the idle up remains on at all times while the a/c is working regardless of compressor cycle. this method is how modern cars use the system.

i've read about people rigging up the idle stop solenoid to produce a higher idle at the flick of a switch for racing. using that in conjunction with a Line lock on the brake system for a off the line punch.

neither of these is what i want. I'm just going to go back at this point put everything as it was and double check the idle rpms with the compressor on and maybe raise it a little to compensate for compressor load on the engine.

i do not having a stalling issue but when coming to a stop and accelerating from a dead stop with the a/c running you can feel a load on the engine and some noise until the RPMS pick up a little then the slight vibration and noise and load on the engine goes away.

I would imagine if i changed to a modern a/c compressor that is a light load on the engine all issues would disappear but i wanted to use the original compressor which is 40 years old and ride this strange pony into the sunset for a while.

 
It sounds like you have a plan. For what it is worth, I think you made the right decision.

Chuck

 
i tossed it back together tonight, and i just raised up the idle so when the headlights/air conditioner and transmission was in gear it was in the 675rpm range. when i turned the A/C off in gear the RPMS only went up maybe 50 rpms.

out of gear its a little higher then i would of liked just over 1000rpms when fully warmed up.

i went for a drive and it really didn't make any difference i may have gone just a touch too high on the new idle but i'll leave it for now and just drive it. i didn't have any problems, the noises the A/C clutch makes when slowing down or idleing is just something i'll get used to, having the A/C on Min and Freezing inside the car when its 96 outside and the engine not overheating at all is just wonderful.

if anything to mess with it again i would just back off the idle RPMS a touch on the screw and adjust my choke down for the summer a little more. i only came up on the idle screw about 45 degrees.

oh i did notice a Very slight engine ping when i touch on the throttle with the a/c going so when i came back from cruising i backed off the vacuum canister one full turn. i climbed a 30 degree incline holding the engine at 40mph all the way up and didn't hear any ping. it was only during Light cruise at 50mph on a flat road and just kissing the pedal i could hear it, so i backed off the vaccum canister 1 turn, and i'll check it over the weekend.

 
Something to be said for AC on a hot summer day. The incline test is a good idea. It sounds like you have it dialed in to me. The slight ping at light load and just barely touching the accelerator pedal may be a little delay/slack in the accelerator pump circuit, more likely just the sub-standard gas we are paying a premium price for. After another round with the new Holley, I've got it as good as it is likely to get. That process is not as much fun as it used to be and the auto trans just makes it even less fun. I should have changed it to a 4 speed at the start of the build, the numbers matching drivetrain persuaded me to keep the C-6. Oh well, next time I'll...............

See Ya,

Chuck

 
The idle solenoid was used to prevent "run on" and emissions reasons. both 71's i ve had were equiped with A/C but the idke didnt change when A/C was on.

"i've read about people rigging up the idle stop solenoid to produce a higher idle at the flick of a switch for racing. using that in conjunction with a Line lock on the brake system for a off the line punch."

I am doing this very thing..... thought it was my idea!:idea:

 
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