setting a Holley 1946

[Anonymous]

Hey guys, I need a little training. The 'stangs running a little rough. How do you adjust the Holley 1946 from start to finish. My timing is set at 12* right now.

 

[mugsy]

What's the dwell set at? A small gap/short dwell time will cause the engine to run rough too. Make sure you get that right, then attack the carb.

tanx,
Mugsy 8)

 

[Anonymous]

Electronic ignition (or whatever's stock on a '79 Mustang Ghia). No points anyway. Single vacuum. Sorry, should have provided more details. 200ci, C4 trans. Stripped down. No a/c, no smog. Bare bones. Timing set at 12* initially. Set idle fuel mix by ear. Would like to do it right. Currently, plug gap is .035. From reading here it should be more like .045 right?

 

[addo]

It certainly won't hurt to open the gap ten thou. Are you setting the hot idle in gear, with the headlights on and blower fan running?

 

[Anonymous]

You're kidding about the headlights and blower fan, right? No. Not in gear. Warmed up though. Here's what I've done.

Set plug gap at .035
Started and warmed up.
Set timing at 12*
Set idle at 600 - 700 rpm (by my oem tach in the dash)
Turned fuel mix in till it stumbled.
Backed it out till fastest idle.
Turned it back in a hair.
Reset idle.
Recheck timing.
Repeat.
Runs good at idle.
Rough in gear with brakes on.
Choke not connected yet.

Opinions? Advice?

 

[Anlushac11]

8)

79 Mustang should have a Duraspark II ignition.

3.3L should be set to .050" plug gap.

My manual is worthless on this. It says check engine compartment decal.

At this point I would start looking for a vacuum leak or a vacuum hose you forgot to reattach.

Failing that make sure plug wires are all attached and in right order.

 

[LaGrasta]

regap at 45 or 50.

bring the idle down to no more than 600.

be sure when setting the timing to have the vac line disconnected AND plugged.

 

[pedal2themetal45]

You're kidding about the headlights and blower fan, right? No. Not in gear. Warmed up though. Here's what I've done.



Opinions? Advice?

No not kidding............... with the blower fan on and the lights on the alt is creating drag on the motor cause it is creating power for battery to cover those acc. and will draw the rpm down when running.. even tho it may be just a little....
For an automatic the idle rpm is set in gear (650 to 700 in Drive.. ) with the park brake applied. as well as adjusting the carb. If you set the idle in "N" when you put it in gear the rpm well drop to low with the drag of the tranny in gear..
Tim

 

[LaGrasta]

I have my RPM set at 575. I am however, a gasmizer.

 

[Anonymous]

regapped the plugs at .048, made a big difference. reset timing per instructions at 12*. readjusted fuel mix. got real vacuum caps and plugged all open vacuum lines like they should be (not with a piece of vac hose and a screw) idle screw is all the way in now, can't go anymore. that's not natural is it? anyway, everything runs much better now. would like to idle it up another 100rpm but can't because of idle screw. any suggestions?

 

[Anonymous]

idle screw is all the way in now, can't go anymore. that's not natural is it?

Float level too high?

 

[Anonymous]

Don't think so but haven't checked it. Bought a reman. at AutoDiscountPepZone. It's about 6 mos. old. Haven't cracked the case on it to check it. Would assume it's set correctly from factory but when you ASSUME....................

 

[LaGrasta]

do you know what your vacume is? SHould be 17-19lbs.

 

[Anonymous]

That I don't know. Don't have a pump and gauge.

 

[pedal2themetal45]

idle screw is all the way in now, can't go anymore. that's not natural is it?

Float level too high?

If the idle screw is all the way in it should be running 900 miles an hour?? do you mean the mixture screw (the one in the base plate of the carb) then No thats not normal.,.. If it runs with that screw all the way in then there is a vacuum leak somewhere or the Idle serew is in to far and is past the idle cercit.
Not to high float level.
I'm not sure about that carb but you may have 3 adjusting screws...
one for fast idle (which is the one you may have all the way in)
one for curb idle
one for fule mixture. (in base plate of carb)
You don't need a pump to check for vacuum just a gage with the motor running you hook up the gage to a manifold vacuum and see what it says. then you can adjust the carb and timming by vacuum if you want find the highest reading and drop it a couple of lbs. of vacuum.
gluck
tim

 

[Anonymous]

do you mean the mixture screw (the one in the base plate of the carb) ..,.. If it runs with that screw all the way in then there is a vacuum leak somewhere

No, a vacuum leak means more air is getting in and would need the idle mixture screw turned out to compensate.

 

[pedal2themetal45]

do you mean the mixture screw (the one in the base plate of the carb) ..,.. If it runs with that screw all the way in then there is a vacuum leak somewhere

No, a vacuum leak means more air is getting in and would need the idle mixture screw turned out to compensate.

I beg to differ but I'm not going to argu..
Its eather a vacuum leak or the throtal blades are open past the idle curcit.
Linc pull a vacuum line and try to adjust you mixture.

tim

 

[JackFish]

Perhaps the screw you are adjusting is the fast idle screw?
I can't see how you could screw something all the way in and still run.
Do you get to it from the driver side?
Assuming the idle solenoid is removed, the idle screw is on the back of the carb's body, accessed from the passenger side, right?
Just trying to get everyone on the same page...
And the idle mixture screw is on the passenger side baseplate, pointing back at about a 45* angle.
Also consider that maybe some screws were mixed up or replaced with the wrong size, or the mix screw is worn out.

 

[Anonymous]

The screw I'm referring to is on the driver's side. So that would be the fast idle screw, right?. Since my choke is disconnected, I'm not accomplishing anything there anyway, right?. I know which is the fuel mixture screw and I feel that it's adjusted properly, at least by ear without properly testing it by checking the manifold vacuum, etc. So I'm turning the wrong screw. My TSP is removed and the screw I should be turning is the one on the passenger side, toward the rear of the carb. It's actually a 3/8 or 5/16 hex head bolt, no slots for a screwdriver. So, if I get a vacuum gauge, I hook into manifold vacuum and tune the fuel mix to the highest vacuum rating? Or the curb idle to the highest vacuum? And then back off a notch, right?

 

[pedal2themetal45]

You use the mixture to best idle (smoothest) reset Idle to spec (650 - 700). You might want to do this a couple of times to get the feel of where it likes it. after you acheved this then turn the mixture screw in just till you hear the RPM start to drop.. this is called a lean drop factory spec..
OH you might want to recheck the timming after all is done. it may change...
good luck
Tim