dieseldazzle
Member
And if this doesnt work absolutely look at intial and total timing
Hmm, trying to remember if this carb has a secondary air valve of some sort... I'll have to take a look tomorrow.
For Sale - NOS Carter AFB
It's not a CAP car, and I'm not running vacuum advance, strictly mechanical. Initial timing is 12°, total is I think around 35-36°.Unless the particular car is a CAP (Cleaner Air System) car, no "real" emissions timing setting. On my '66 Newport 383 2bbl, the base timing was 12.5 degrees BTDC. CBODY67
Yes I've been thinking that also, a "modern" carb would probably be money well spent. But the distributor hasn't been upgraded yet either. It is the original and still running points. It is probably worn to some degree. All this ancient stuff on the engine is still working remarkably well considering.That is a really small carburetor to not have the counterweighted air valve. Except for a 1000 point resto of a museum piece, for drivability and reliability a new carb would be on my radar...
I'm also curious about the same thing. Very curious. From what I remember in the dark ages, both my '65 Barracuda 273 and '61 300-G 413 carbs had them.Wonder what the reasoning is behind some with secondary air valves and some without. (???)
I would get that vacuum advance working again. The fuel mileage alone is worth it, let alone that it will make your engine live longer.I'm not running vacuum advance
Set the timing with a vacuum guage. Most carburetor problems are electrical.
Unless the particular car is a CAP (Cleaner Air System) car, no "real" emissions timing setting. On my '66 Newport 383 2bbl, the base timing was 12.5 degrees BTDC. I usually ran it at 15 degrees as we used premium fuel (it clattered on regular from day one!). I could set the idle speed by simply advancing the timing, from the settings at 12.5 degrees BTDC. It was possible to set the idle mixture to the CAP spec 14.2 A/F ratio on this non-CAP carb, but I kept it at the normal "max rpm" idle mixture, or what was later termed "best lean idle".
In setting idle mixtures, the process evolved for a few years after '66. Normally, the procedure was to set it to max rpm for the speed setting at the idle speed screw. Then tweak the idle speed down with that screw, as needed.
Later, once the spec speed was initially set, you adjusted the idle mixture screws for max rpm, but also leaned them until you got a 20rpm drop if any further leanness was attempted, then returned to the prior max rpm. In the first case, you maxed the rpm for the given idle speed screw setting, later, you verified that it wasn't too rich by going a little lean to verify that, too.
Using a vacuum gauge can be problematic, especially IF you try to hit a particular vacuum level at idle. Vac gauges can vary, as the vacuum can also vary with altitude and possibly barometric pressure. Use it as a diagnostic tool, only, which it CAN be very good at on many engines.
As with any diagnosis, the more data points you can collect, the possibly more accurate the diagnosis can be.
CBODY67
Some of the early CAP carbs used pinned idle mixture screws that prevented them ftom being turned out too far and making the mixture rich. Mopar used a propane enrichment system which artificially enriched the mixture with propane gas, introduced thru a constant vacuum connection to achieve a smooth idle, then the idle speed set, then the propane wss removed resulting a lean idle. Then there was the electric retard vacuum advance on the distributor .....what a pain in the ***.....
Good reason for putting it on a shelf and keeping it with the car as it changes owners. To drive it you need something with more range of adjustment. Stuff like that was put on a car at the time not to make everyone's life easier, so now that the cars have passed into casual use why not make them more user friendly.Some of the early CAP carbs used pinned idle mixture screws that prevented them ftom being turned out too far and making the mixture rich. Mopar used a propane enrichment system which artificially enriched the mixture with propane gas, introduced thru a constant vacuum connection to achieve a smooth idle, then the idle speed set, then the propane wss removed resulting a lean idle. Then there was the electric retard vacuum advance on the distributor .....what a pain in the ***.....
It's not a CAP car, and I'm not running vacuum advance, strictly mechanical. Initial timing is 12°, total is I think around 35-36°.
Yes I've been thinking that also, a "modern" carb would probably be money well spent. But the distributor hasn't been upgraded yet either. It is the original and still running points. It is probably worn to some degree. All this ancient stuff on the engine is still working remarkably well considering.
I'm also curious about the same thing. Very curious. From what I remember in the dark ages, both my '65 Barracuda 273 and '61 300-G 413 carbs had them.
I really appreciate everyone's insight into this issue I'm having. I'm also thinking my bog issue may possibly be exacerbated by the lack of a torque converter in the car. I think for now I'll keep things status quo. Maybe do another rebuild on the carb. Maybe check the timing chain. After I get the reupholstered seats back in.....