Ford Muscle Cars Tech Forum banner

1 - 20 of 27 Posts

·
Registered
Joined
·
22 Posts
Discussion Starter · #1 ·
Hi, just purchased my 65 with a 352. I noticed the vacuum advance hose was not connected to anything, the previous owner has all the ports on the holley 4bbl capped and the hose coming off the vacuum advance was crimped and tucked under the distributor. He said "it runs better like that". I thought this was weird so i just completely capped the vacuum advance. Once i did that the trans would not shift, so i ended up removing the cap completely on the advance, so now i just have open air going into the vacuum advance. It seems to shift perfect now, and I "Think" its running ok, but i feel like its still not right. Does the vacuum advance need to be connected to the carb? or does it just depend on the setup of the motor? thanks for advice!

-jamie
 

·
Registered
Joined
·
10,327 Posts
The trans shifts are altered based on vacuum to the trans modulator, but that has nothing to do with your ignition advance. Assuming you have no or minor engine mods, I would suggest referring to your factory service manual to set it all up as stock. While there are other schemes for ignition tuning, unless you are doing something specific for a purpose, altering the system will almost always result in both lower power and less fuel economy. If it really runs better with the distributor vacuum disconnected, then something is not right and needs to be corrected. Properly functioning ignition vac advance is an important part of street power, mileage, and engine longevity.

David
 

·
Registered
Joined
·
22 Posts
Discussion Starter · #3 ·
The trans shifts are altered based on vacuum to the trans modulator, but that has nothing to do with your ignition advance. Assuming you have no or minor engine mods, I would suggest referring to your factory service manual to set it all up as stock. While there are other schemes for ignition tuning, unless you are doing something specific for a purpose, altering the system will almost always result in both lower power and less fuel economy. If it really runs better with the distributor vacuum disconnected, then something is not right and needs to be corrected. Properly functioning ignition vac advance is an important part of street power, mileage, and engine longevity.

David
looked through the shop manual for 1965 Fords but there is nothing regarding proper placement of vacuum lines or the vacuum advance line. I think i will just try hooking it up to an available port on the carb and see what happens..... trial and error :)
 

·
Registered
Joined
·
10,327 Posts
Ah, that's right - the manuals didn't cover vacuum diagrams until '67. IIRC the '65 to '68 are the same, so maybe you can source a later one.

David
 

·
Premium Member
Joined
·
5,912 Posts
On my 65 352 with a 4100 carb... Vacuum hard tube from the middle right side of carb to the distributor. Vacuum fitting on back top of intake splits, one to the booster check valve, one to the storage cannister. From the booster check valve a vacuum hose to the cruisomatic. From the cannister, vacuum hose to the firewall, then to the bottom of the selectair lever. Vacuum hose from the PCV to a nipple at the rear of the spacer below the carburetor.

From the selectomatic lever, three hoses red aqnd white to the door solenoids below the glove box and a blue hose back out to the firewall, where it controls the Heat/AC door and the heater hose water valve.
 

·
Registered
Joined
·
5,337 Posts
The vacuum advance should be sourced from a ported vacuum nipple @ the carb.

As for the trans not shifting properly, you must have disturbed the manifold vacuum source to the modulator valve in some way.
 

·
Registered
Joined
·
22 Posts
Discussion Starter · #7 ·
Thank you all for the help! I've been outa town for 2 days now, finally back home tomorrow and cannot wait to get under the hood. I'll let y'all know how I end up!


Sent from my iPhone using AG Free
 

·
Registered
Joined
·
22 Posts
Discussion Starter · #8 ·
well this morning i called SMI Carburetor (www.smicarburetor.com) because i found out per the previous owner that they were the company that installed and tuned the 4bbl Holley carb on my galaxie, and also stated that they were the ones who un-hooked the vacuum advance line. SMI carb told me that there are times when they will leave the vacuum advance unhooked because the motor simply runs better without it. They are a very reputable company so i trust them, but i tested it out on my own anyways. Every time i hooked the vacuum advance to a port on the carb the motor seemed to sputter or misfire a bit. I still may try hooking it to the maniford vacuum port tree. So i guess they are right so far, regards to leaving the vacuum advance unhooked, unless anyone else has any other ideas? I am going to take some pics of my motor and post them ASAP.
 

·
Registered
Joined
·
10,327 Posts
They may know carbs, but they (or someone that works for them) don't know ignition. If the engine runs worse in any way with the vac line connected, then the carb was not properly tuned or adjusted to proper ignition. Unfortunately, to make their carb work easier they altered or mis-adjusted the ignition to fit it, rather than the other way around. Normal practice is to set basic ignition parameters first (including vac advance), and then adjust the carb to peak performance. While the ignition may be tweaked during tuning, it is always adjusted to the engine and what it needs, and the carb is adjusted to the engine and the ignition. Never the other way around.

The ignition should be reset to stock parameters, and if it runs worse, then the carb should be tuned-in to match. Then the ignition final tuned for peak efficiency and performance, and again the carb tuned to final match. If some hired hand at SMI actually tuned their carb by altering ignition, then hiss-boo on them, and I don't criticize other's work without cause. :frown: If there was an ignition problem ("not their job"?) then they should have made it clear to you that ignition service was required and then a carb re-tune. Maybe you didn't understand the message if they tried to tell you? Perhaps a call to the owner will get the process corrected and both carb and ignition tuning done right. I'm sure they don't want a slacker on the crew that isn't doing the right thing in the best interest of their customer.

David
 

·
Registered
Joined
·
22 Posts
Discussion Starter · #10 ·
Thank you for your insight. If i cannot figure it out I think i may drive the car over there tomorrow. I was just talking to a guy on the phone over there, but i bet your right, if i show up and show them exactly what is going on maybe they can help me out. Seeing as i was not the original customer (the previous owner was) they may tell me to pound sand, but hopefully not :)
 

·
Registered
Joined
·
2,797 Posts
Don't know where you are in So-Cal but there are two places in the L.A. area that can help. One in Alhambra and one in Orange.
 

·
Registered
Joined
·
5,337 Posts
We left the vacuum advance feature disconnected because we found the car runs better without it... :confused:

(Or the previous owner did not want to pay shop labor to chase it)

Did they re-curve the distributor to only have mechanical advance? Doubt it. If one has a performance problem with the vacuum advance connected and none while disconnected, it is either a vacuum leak (hose/diaphragm) or the breaker plates may be frozen/binding.

Once again, the vacuum advance (on this period FORD) is designed to operate off ported vacuum, not full manifold vacuum.

Just because you take it to a supposedly professional shop means that it will be done correctly.
 

·
Registered
Joined
·
22 Posts
Discussion Starter · #14 ·
Well I've tried everything possible to connect the vacuum advance and everytime the motor Boggs down or seems to want to die. So far my conclusion is that it does actually run better not connected to anything. I cannot tell if it has performance issues not being connected because it seems to run fine, and accelerate well. But since I've never driven any other galaxie with a 353, I have nothing to compare it to :-/


Sent from my iPhone using AG Free
 

·
Registered
Joined
·
5,337 Posts
:(

Do you have a timing light?

Do you understand how breaker plates and a vacuum advance feature actually works?
 

·
Premium Member
Joined
·
5,912 Posts
Well I've tried everything possible to connect the vacuum advance and everytime the motor Boggs down or seems to want to die.
Mine did that. So I put a hose on the cannister and sucked and the lever in the distributor pulled back like 1/2". I tried to adjust the pull in the cannister but the allen head screw in there was missing. So I got a new cannister, turned the screw CCW and now all is good.

You can probably test yours while the engine is idling, plug a hose in there and suck and see the the bogging occurs.
 

·
Registered
Joined
·
22 Posts
Discussion Starter · #17 ·
:(

Do you have a timing light?

Do you understand how breaker plates and a vacuum advance feature actually works?
I do not have a timing light, and all I know is the vacuum advance helps in regards to ignition and firing to the pistons, other then that, I've really never taken the time to learn about it.


Sent from my iPhone using AG Free
 

·
Registered
Joined
·
2,797 Posts
Try Bill's Auto Repair, 1523 W. Struck, Units J & K, Orange, 714-639-3410. He is a 60's and earlier Ford expert.
 
1 - 20 of 27 Posts
Top