225 Slant needs a good idle. what rpms are you spinning?

[Johnny71dusty]

Too retarded isn't good either. Maybe it needs to go the other way?

It's running at 20 degrees advance at idle at 1000-1200 rpm . With vacuum advance off . And if distributor goes the other way that advances it to over 40 degrees

 

[volaredon]

If you're idling at 1000-1200 you're into the mechanical advance. So you're not seeing true timing.

 

[Bugman]

what carb are you runing

 

[Johnny71dusty]

what carb are you runing

Original carter b&b . Well a newly rebuilt one i got from a well know eBay store . It was only place that had one

 

[Johnny71dusty]

If you're idling at 1000-1200 you're into the mechanical advance. So you're not seeing true timing.

Even if my hose is off and capped ? Ok I get that I think . But nothing I do can get idle under 1000-1200 . And it's very not consistent . & stalls a lot

 

[Bugman]

That is carter BBS 1 bbl era 70-71 with hot idle compensation valve, look like that one

 

[Bugman]

how about this one

 

[volaredon]

Centrifugal advance is just that....
Think about the last time you rode a tilt a whirl/ didn't it seem you were "smashed" into the back wall of the car the faster it spun? The faster the engine turns the farther the weights want to extend from center til they "max out" in the slots, if everything moves freely the springs control how fast they extended out.
The weights could be "stuck" at some point extended out from center, too.

It definitely sounds vacuum leak related the more I read into your posts.
whether it is at the manifold/head interface or within the carb but I bring up timing because the farther it is advanced the faster it will idle, everything else equal.

 

[Mattax]

If you're idling at 1000-1200 you're into the mechanical advance. So you're not seeing true timing.

Exactly.
Just illustrated that for another guy here

 

[RustyRatRod]

Wow, old thread, but what the heck. I can idle Vixen down to about 400, BUT she will stall coming to a stop. Her happy place is right around 900. Since she does have a pretty large cam (250 @.050" duration ground on a 108 LSA), I'm sure that has something to do with it. Manual transmission, so it's pretty forgiving. The T port slots are also squared up at 900, too so that part is right on the money.

 

[AJ/FormS]

If the throttle is closed, the engine cannot run unless it is getting air somewhere UNDERNEATH the throttles.
Just Cuz the Idle speed screw is all the way out, does Not mean the throttles are closed, nor that the engine isn't getting air somewhere else.
At idle, the more timing you give it, the higher will be the idle speed, up to about 25/30 degrees. After that the engine may begin to complain after it warms up.
If the valve lash is too tight, it will complain sooner.
How many parhs are there into the combustion chambers? Trick question; Four, the intake valve AND the exhaust valve, and the two valve stems.And that's if the head gasket is sealed
How many paths are there into the intake port?
Well besides the throttles ... there is the PCV, the Booster hose, possibly an internal air bypass system, a hot-idle compensator, a base gasket, the intake to head gasket, and possibly a cracked exhaust manifold under the intake plenum, Or if the engine has an EGR valve/passage, add that to the list. Soooo like said;
Just Cuz the Idle speed screw is all the way out, does Not mean the throttles are closed, nor that the engine isn't getting air somewhere else.

 

[Bugman]

Losen that bolt on bottom of distributor, move in slot for better adjustability. 20 degrees before top dead center at idle that will need at least 700 rpm to prevent rough runing. Any slower than that peak combustion pressure will occur on the wrong side of top dead center

 

[Bugman]

some times hole in throttle plate for more idle air with out opening throttle plate

 

[Scooper]

Yea I get you but not my issue . My ideal screw is all the way out . It's still field very rough at 1000-1200 . Even with distributor all the way retarded . Yes already pulled thr distributor and too dead center and Tried move plugs over one spot to see about getting to closer . It's acting like classic vacuum leak but can't find one anywhere . The motor prior to head swap ran very low rpms , never once stalled , had way more power in pedal . The new head has 100 thousands off and should have slightly better compression and more power. But it's now a total dog and idle high . Stalls , has no power even at full throttle . I'm about to set the car on fire

You absolutely have a vacuum leak if you have to run your idle mixture screw out that far. Put some gasoline in an old squirt bottle and just give 'r a shot around any vaccum hoses, and the carburetor. It could also be leaking from the intake manifold where it seals to the head. You could try hitting it with a shot of ether near the base of each intake runner.

The idea here is, if you do either of those two things, and you find a spot where when you do it, your idle smooths out (and very likely slows down), then there's your huckleberry. That would be where your vacuum leak is.