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FFCobra Fanatic
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Discussion Starter · #1 ·
I'm no mechanic so please try to keep it simple for my 56 year old brain!!

OK, I need some tech advice.

Just received a 85 carb from a mustang forum member. It's the Holley 4180c.
He says it worked well when pulled.

I'm looking at a Edelbrock Performer RPM intake (non-EGR) for my 87 carb conversion. Also, a 1 wire Procomp dist with HEI on the dist cap.

Am I going in the right direction??? Any advice would be appreciated.

Also, the carb has 2 electrical connections. What are they for? One (a 2 wire for kick down, I believe (what's a kickdown???) the other is for an air conditioning disconnect at WOT??!! Am I correct with these assumptions? Can they be deleted on the conversion to carb?

Any guidance would be appreciated.

[ April 06, 2007, 06:42 PM: Message edited by: Duper ]
 

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FFCobra Fanatic
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Are we talking the stock carb that came on the 85 mustang? Probally not the best in way of a performance carb. Without seeing the carb thinking the elec. connections are one for choke,other for fast idle control for a/c equiped cars or maybe a bowl vent solenoid. If having a choice I would use aftermarket carb not OEM carb but it will work.
 

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I haven't looked at my stock carb in years, but I recall a 2-wire connector for the a/c cut-out (normally closed switch) and a single wire for the throttle kicker (a/c on). The choke should be pretty obvious on the other side of the carb. It's not a bad carb, but I'm with Hind Sight in suggesting you consider an aftermarket version. If you're emissions regulated however, it can be made to work fine. If you do go aftermarket, keep the choke stat from the '85. It works much better than the Holley issued choke stat and they are expensive.
 

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I had an '84GT with that carb, which ran ok, but never really as good as I wanted, so I switched the intake out for a performer, with a standard, vac. secondary 600 Holley, and the difference in not only how it ran, but the performance of the car was day and night! I would just go that route if I were you, and sell that carb to someone restoring the '84-'85 vintage stangs. By the way, if you are looking for a performer intake, I have a super nice one in the classified section, or just pm me...

Brian
 

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FFCobra Fanatic
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Discussion Starter · #5 ·
Thanks guys.It is a stock carb from an 85.

Here are a few pics of the elec. connectors. Can't see any connection on the choke side??!







 

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FFCobra Fanatic
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Discussion Starter · #6 ·
Does anyone have pics of an application like this? I really don't need an electric choke and whatever the other connection is for, I probably don't need it either. The carb did come from an 85 GT, 5 spd, not an auto, so it's probably not a kickdown connection.

Also, anyone know any links that refer to the Holley 4180c. I can't find anything on Holley's web site. Google helped...... a little, but I can't find out about the electric connections.
 

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2010 FFCars Graduate
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I had an 85 GT. That little stud sticking out of the choke is where the wire goes on it. The other two are what you called them. Yes it did kick the a/c compressor out at WOT. The other is the throttle kicker. It holds the throttle open a bit when you turn on the key and then bumps up the idle when you turn on the a/c. It also closes the throttle all the way when you shut the car off to help prevent run-on.
Having said all that the car always had a lean stumble that I could never really get rid of.
And did you notice you can't adjust the idle mix?
I always called it the sort of Holley.
It will probably work but I doubt you'll be real happy with it.
 

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What speed2 said. The idle mixture is adjustable if you access the screws. It has 4 idle mixture screws. They are under the bowls in the base plate. They are inside the 4 round tubes angling out that probably still have a plug in the end of each one. The plugs kept the customers from playing with them. Usually a slot cut in the bottom of the tubes will let you knock the plugs out. It's an odd duck for sure.
 

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Discussion Starter · #9 ·
Speed2much and Highspeed,

THANK YOU!!!! So I guess I can delete these 2 units from the carb, yes?

The 4180c was made by Holley for Ford especially designed for the car owner not screw around with the carb and muck up the emissions as decreed by Big Brother. My carb has the primary plugs removed already but the rears are still in place.

It's great to have a place to go and get info fast!

Bill
 

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Discussion Starter · #10 ·
So, I'll ask again, I guess I can delete these 2 units from the carb. Am I right?
 

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section 8
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from personal experience delete the carb. I swapped an 85 GT engine into an early ranger pickup and any modification to the engine is limited by the carb.Even just an intake swap .The lack of a rear metering block is the problem .There is a kit to fit one but your better off with a different (bigger) carb.My race Fairmont uses an x cam ,stealth intake and a 780double pumper Carb.The ranger ran best with a stealth and a 700 double pumper . Look in your ford racing catalog all 302 engine with a power rating are tested with a 780 caeb.... Sorry for the bad news Bob
 

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FFCobra Craftsman
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Duper,
I ran these carbs in two different Mustangs and a Ranger pickup conversion.
Several modifications:
1) Unbury the front idle adjust screws in the throttle body
2) Use a rear metering block kit from Holley for the secondary jetting
3) Replace the two stage power valve with a single stage unit.
4) The idle speed solenoid and microswitch that you see are for A/C operation and do not need to be used for your application. Look on the throttle body and drill a hole for an idle speed screw that contacts the throttle shaft and you can eliminate these parts. The screw is in the same position as an 1850 Holley, which you can view on the Summit website.
Best regards,
Chuck
 

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FFCobra Fanatic
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Like said the solenoid and switch can be eliminated. Adjust the choke so it stays open. This can be done by rotating the housing. This is an emissions carb. This means you only have 2 mixture adjustment screws on the primary side of carb. Screws work backwards from a performance holley meaning when screw is turned out,it makes mixture leaner instead of richer. May also have limiter on screw only allowing them to be turned 1 turn. Check to be sure if still there. No jetting can be done to secondarys since you have no metering block but only metering plate or fixed jets. Again if possible use a performance carb as this has very limited adjustments for tuneing, and maybe sell this to someone wanting an original.
 

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I inquired of Holley about the metering block for the 4180C and was told they do not have a conversion kit for the 4180c. Does anyone know the part number of the kit? Does the main body require modification? I have seent he one kit Holley offers for I believe it is the 4150 is this the one you need for the 4180c?

Thanks everyone.

George
 

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George not sure you can adapt the metering block conversion kit on to the emmision carb 4180.
Best if you can compare side by side the metering plates and main body of the 4150 and 4180 to see the hole locations.
Like mentioned these carbs are not performance carb's. They were meant to run lean and pass emmisions before EFI became popular. There are some mods a good carb tuner could make to help, but unless needing this carb to keep originality. Better off with a aftermarket piece.
 

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The metering plate is different for sure. The carb does however have idle mixture screws on the secondary side located in the base of the carb just like on the primary side. There is a 4180c for sale on eBay right now with the metering block conversion done to it. I have also heard from other sources that a metering block can be installed on the 4180c. But since the metering plate is different I am guessing that the carb body has passages in different locations. That being said I doubt the metering block conversion would work with out modifications to the carb body.

How sure are you that the idle mixture screws are backwards from the standard performance Holley. I recently adjusted mine and turning the screw counter clockwise increased the idle speed and vacuum as well as improved the cold idle as well as reponse. I know my car is running lean as the plugs are are only lightly tan on the tip of the center insulator. This is the reason for wanting the metering block conversiion.

The carb is jetted with 70's on the primary side and the metering plate is drilled two sizes oversize and it is still lean. I have checked for vacuum leaks and do not detect any. Other than the lean condition as shown by the plugs and confirmed by my wide band A/F gauge the car runs good. My other Capri 5.0 all stock the plugs are the nice tan color on the center insulator.

Guess I may have to spring for a new vacuum secondary Holley.

Thanks
 

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FFCobra Fanatic
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Almost all had reverse mixture screws. Some times it will be marked at the mixture screw itself showing little arrows indicating direction to turn screw for rich or lean. When you turned the screws out did you see the afr get richer on the wide band or did engine respond with better vacum,idle due to it being already too rich at idle?
Where is the engine too lean now? Only when cruiseing and main jet is metering fuel or at idle and low speeds where idle jet and transition curcuit is metering feul. Both the idle and transition curcuits can be made richer,but these are internal mods made by emlargeing idle feed restrictor,smaller idle air bleeds,or transition slot orfice.
What is present afr at idle,low speed low load cruise, steady cruise and wot?
 

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The wideband was not installed when I adjusted the idle mixture. Speed increased and vacuum increased when I adjusted the carb. It is lean at low cruise 40 mph will have to do some additional checking this weekend for idle and higher speed cruise. Can't beleive it was rich at idle before since the plugs were white before and after adjusting idle mixture. It responded with better vacuum, better idle, better cold idle, less surging at 40 mph.

Thanks for all your help Hind Sight. I will post more after this weekend when I have the time to drive the car again. Work interfers with life!!

Thanks again.

George
 

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I have some experience with that model carb. I too owned an 85' GT the last of the carburetted V8s. It is a 590 CFM and jetted extremely lean like 20:1. You will have to jet up to 67 primary and 75 secondary and you will still give up 20 Hp and 20 ft/lb vs a regular old Holley 650. I agree with the others it is too restrictive on the top end.
 
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