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2/15/2020 6:05 PM  #1


Idle Solenoid for A/C

Guys,

I was thinking. Those that have a/c and carbs, do you use a solenoid to compensate for the idle speed drop when the compressor kicks in?
 


Gary Zilik - Pine Junction, Colorado - 67 Coupe, 289-4V, T5
 

2/15/2020 6:55 PM  #2


Re: Idle Solenoid for A/C

Don’t have one on mine. I considered it at installation but I only got about a 50 - 75 rpm drop when it kicked on.
The 331 seems to handle it quite well without wanting to thrash around in the engine bay.


Good work ain't cheap, Cheap work ain't good!   Simple Man
 

2/15/2020 10:40 PM  #3


Re: Idle Solenoid for A/C

Never found one that would kick enough without my help. I just put up with it so far. Maybe with this different refrigerant and less head psi solves the stall at times.   Will see as the bash nears 

 

2/16/2020 8:16 AM  #4


Re: Idle Solenoid for A/C

I installed a Vintage A/C system and have not found any impact to the idle speed and did not have to make any adjustments to the idle speed or the idle mixture screws. 


65 Fastback, 351W, 5-speed, 4 wheel discs, 9" rear,  R&C Front End.
 

2/16/2020 10:44 AM  #5


Re: Idle Solenoid for A/C

Yes, Holley has a bracket and solenoid that works well.


John  -- 67 Mustang Coupe 390 5 speed
 

2/16/2020 11:09 AM  #6


Re: Idle Solenoid for A/C

Bolted to Floor wrote:

Yes, Holley has a bracket and solenoid that works well.

That one wasn't strong enough when I tried it for my setup.  Just couldn't kick the idle up on it's own. Weaker throttle return spring, it would, but dangerous. Commercial engine idle ups solenoids too expensive and vac. pods don't work well with mid size cams.
 

 

2/16/2020 11:33 AM  #7


Re: Idle Solenoid for A/C

Bolted to Floor wrote:

Yes, Holley has a bracket and solenoid that works well.

So it seems some do and some don't and some live with it. I think it would drive me nuts if the idle dropped each time the compressor kicked in. I think I'll spend the bucks and find one. I will have to fab my own bracket as I'm running a Summit M2008 series carb.


Gary Zilik - Pine Junction, Colorado - 67 Coupe, 289-4V, T5
     Thread Starter
 

2/16/2020 12:37 PM  #8


Re: Idle Solenoid for A/C

red351 wrote:

Bolted to Floor wrote:

Yes, Holley has a bracket and solenoid that works well.

That one wasn't strong enough when I tried it for my setup.  Just couldn't kick the idle up on it's own. Weaker throttle return spring, it would, but dangerous. Commercial engine idle ups solenoids too expensive and vac. pods don't work well with mid size cams.
 

 
Red, did have to do some adjusting on it to get it right for me. Sounds like I my throttle return spring might no be a strong as yours.

Gary, it seems like that bracket was less than $20. Might be a descent starting point.



John  -- 67 Mustang Coupe 390 5 speed
 

2/16/2020 1:10 PM  #9


Re: Idle Solenoid for A/C

I do not have one on my 427.  Idle drop is negligible, but I do increase my idle speed in the summer months just a tiny bit.  In Tx, during the summer, if the car is on, the ac is on full speed.


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
 

2/16/2020 1:32 PM  #10


Re: Idle Solenoid for A/C

I installed one on my '65. Since I have a Holley carb I got the Holley solenoid.
And no, the solenoid is not powerful enough to push the throttle lever on the carb on it's own. You have to step on the go pedal and then the plunger extends. It is strong enough to prevent the throttle from closing to it's normal idle setting.

 

2/16/2020 2:19 PM  #11


Re: Idle Solenoid for A/C

I'm to old skool to give up on the York compressor. The ones that had the big John Deer flywheel on the clutch help with the engine stall in 90 deg. plus heat, but when that sucker came off one day, I forgot about how hot it was.

 

2/18/2020 10:36 PM  #12


 

2/19/2020 8:53 AM  #13


Re: Idle Solenoid for A/C

Need to run more cam so your basic idle speed needs to be high enough to survive all those wimpy loads!

 

2/19/2020 9:35 AM  #14


Re: Idle Solenoid for A/C

DC wrote:

Need to run more cam so your basic idle speed needs to be high enough to survive all those wimpy loads!

 
I like this answer  ^^^^^^^^^^^^^^ !!   If it idles below 900RPM's is it REALLY a  Mustang?!!
6sal6


Get busy Liv'in or get busy Die'n....Host of the 2020 Bash at the Beach/The only Bash that got cancelled  )8
 

2/19/2020 11:42 AM  #15


Re: Idle Solenoid for A/C

Big Cam, got it!


Gary Zilik - Pine Junction, Colorado - 67 Coupe, 289-4V, T5
     Thread Starter
 

Board footera


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