Timing /6 without advance port of the carb working correctly??

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FURY440

FURY440

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1966 225/6. Since I have an issue with my Carter 1695 1bbl that has constant vacuum at the Advance port that should be ported. Should there be vacuum at this port at idle? Idle is between 600 to 700.
Has anyone set the timing without using the advance port on the carb and leaving it disconnected? Setting it to maybe 10 to 12 degrees BTDC at idle and letting centrifugal force do the rest? Or total advance between 32 to 38? Is this possible until I can figure out whats going on with this carb. Think I can get away with this?
 
The vacuum pod is the thing you should set last. Get your car fully tuned without it. Your car will run and drive just fine with it unplugged.

There should be minimal vacuum, if any at all, at the ported vacuum port at idle.
 
Thank you. The car is tuned up with all new parts and set correctly. The advance port on the carb has constant vacuum. Not zero or even minimal,... Full vacuum at idle. So would I be safe to set it at idle 10 to 12 degrees BTDC and or a total of 32 to 38? I know Mopars love timing.
 
i'd start at 10 degrees advanced and go from there
if you're using a stock or reman stock distributor you will most likely have too much mechanical timing and need to weld up the advance holes a little
 
Yes I agree,.that's why I was saying between 32 and 38 total and then check it at idle for initial timing.
 
I contacted Mikes Carburetor Parts and asked him what he thought. This is what he said.

"Some engines, starting in the 60's, had full vacuum to the distributor. Ported vacuum signal for the distributor advance came from above the throttle plate at idle. As the engine speed was increased, incoming air rushed by the now open port and created a vacuum signal. This signal would advance the timing 8 to 12 degrees. Starting in the mid to late 60's some manufactures modified the distributor curve and camshaft to create less emissions and along with these modifications came the full vacuum signal to the advance! You need to research this application to determine if you need full or ported vacuum signal. If ported is required, then you may have the wrong carburetor. I can install a ported circuit in most carbs buy drilling a small circuit above the throttle plate. You can also do this about 1/8" above the plate at idle position"

Hopefully this helps
Thanks
 
Thanks Dan. How about that,.so I'm guessing the carb is wrong for my 225? It doesn't have a port just above the throttle plate. See picture of my carb.
IMG_08181.png
 
Impossible to tell where your advance port except by removing the carb. This what you're pointing at is just the external vacuum nipple. It's in the same place on all Carter BBS carbs; what differs is the placement of the inner end of the passage that nipple connects to: above or below the throttle plate at idle. Also note that if the throttle plate is not where it's supposed to be, the vacuum advance signal won't be timed/ported correctly. Reasons for improper throttle plate position include other wrong settings (fuel mixture and base spark advance set wrong = have to open the throttle plate further to get the right idle speed = vacuum port uncovered when it should be covered) or slop at the throttle shaft where it passes through the throttle body. There is no off-the-shelf/replaceable throttle bushing in any carb used as factory equipment on the Slant-6. If there's side slop in the throttle shaft-to-throttle-body junction, you need to have it rebushed by a suitably skilled machinist.

Also, the correct rubber bushing for the throttle lever (where the rod enters it) is available new from Gary Goers as part № 415 -- important to use that; a piece of hose or tape shoved in the throttle lever (as appears to be the case on your carb) is a common fix, but not a safe one. For details on Gary Goers see here (part № 415 is on page 18).

Carburetor operation and repair manuals and links to training movies and carb repair/modification threads are posted here for free download.
 
Thanks again Dan. By chance would you know what the base timing would be on my /6? 1966.
 
Try a setting of 5° BTDC with the engine idling at 650 rpm and the vacuum advance hose removed from the distributor and plugged.
 
Oh boy. Checked the timing and it's about 5° BTDC, but I can't get anymore out of it. Distributor hold down bracket is at it's max for any more adjustment. I could remove it and slot it more to get more advance. Like to see where the engine likes it. Most Mopars like more timing. At least my 440 and 383 did.
 
Look on the underside of the distributor for a second adjustment slot. Put a dentist mirror under there and look up.
I have a 64 225 with a BBS Carter and my vacuum is zero, at idle, at the port you pointed to.
 
I see another adjustment bolt like you said on the bottom, but to get to it,.I would need to remove the oil filter.

Man I've been out of the loop for a long time and haven't owned a /6 since the early 80 or less. I've always had big block cars and very few /6's.

With the dizzy having this extra adjustment bolt on the bottom,.do I need to loosen the normal adjustment bolt and the one on the bottom to get more timing? Or do I just loosen the bottom bolt and adjust? Doesn't seem I can get to that bottom bolt without removing the oil filter. So this won't be possible to set the timing using that bottom bolt.
 
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FURY440 said:
I see another adjustment bolt like you said on the bottom, but to get to it,.I would need to remove the oil filter.
Click to expand...

Or pull the distributor. Or use the correct wrench to reach that underside bolt with the distributor in place.

With the dizzy having this extra adjustment bolt on the bottom,.do I need to loosen the normal adjustment bolt and the one on the bottom to get more timing?
Click to expand...

The one on the underside of the distributor has a longer slot than the accessible one. Loosen the underside bolt and move the hold-down plate a little to gain additional room on the accessible slot. But 5°BTDC is a fine setting, so for now you could just leave everything as-is.
 
I did not know that Chrysler ran full vacuum to the can in early years
I have had 4 slantys, a 65,a 69,a 77 and an 80, and all of them had proper timed sparkports.
>If I was working on your car, I would disconnect that hose from the spark-port, and start cranking advance into it until the rpm stopped rising, without to regard to how much; I would just crank it. Then I would slow the engine down with the curb-idle screw to 600ish. Then I would check that port for vacuum.If I now had zero on the gauge, I would next crank the speed screw back in until vacuum reappeared at the port, just a tiny bit.And then I would retard the timing until the rpm fell to 650. And finally I would reduce the rpm to 600ish, with the adjuster screw. Then I would read the timing.If the timing was not close to spec I would verify the TDC mark with a piston-stop.Having proved or corrected the mark, I would then recheck the timing.
>If I now found that the timing was ATDC, I know that that was normal on certain year slantys.I never liked that and all my three slantys, and others besides, liked a lot more.But to change it now, means destroying the Sparkport sync, so the next thing I would do is check the power-timing, with the Vcan disconnected. If I found that to be in spec, I would be tempted to call it done.
>At this point I have some choices; verify that the carb is the correct year carb for the application, and if it is, I can leave it,or I can mod it. Modding it takes time.
>But if the power-timing is NOT sufficient, then It will have to fix that first. And with retarded idle-timing, this is easy, just advance it. But if you then slow down the idle speed with the screw,that will again destroy the previously established sync. So now it becomes even more important to prove that carb is correct for the year, and if it is , what was Mother's thinking? I have to know if she had any controls on that port or was it direct to manifold vacuum, and if it was, why was the nipple even on the carb?
>Well,well, looky what I found.These specs are for a 69.
Idle-Timing on a 225 is TDC@ 550
Mechanical advance is to be; 2/10*@1100, 19/23*@ 2300, 24/28*@4000rpm.
Vacuum can is to deliver .5 to 3.5* @10 inches, 5.25 to7.75@16inches
All the Carters I found had the sparkport above the plate;for 69. But they were all RIGHT above the plate, so that means it wouldn't take much out-of-sync to activate the Vcan, and it doesn't take much vacuum to get the Vcan excited.
>So as you can see, for 69 at least, Things were tuff for the poor slanty.
>So that takes us back to what I would do, And that is still what I would do.

> another thing to help you is to pop the carb off, flip it upside down,and check the t-port sync.The transfer port exposure should look like a little square, and the sparkport should be above the plate, IMO. Adjustment is with the curb idle screw.
>If the engine idles too slow at this setting, Either; A) the valve lash is too tight,or B) the fuel level in the bowl is too low,or C) the engine is sucking air,or D) the timing needs to be advanced,heehee, or E) the plug gaps are too wide, or F) the convertor is dragging.

Done,Ithink .
 
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