CAP: Keep or Delete? The Next One has it...

Gerald Morris

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Greetings Esteemed Moparians!

While perusing the engine compartment pic for the Next Newport, I noticed the distributor control valve in back of the Carter B & B carb that indicates a CAP setup.

Trudy-CAP-system.png


The current owner complained of the carburetor malfunctioning, but I now suspect maladjustment as much as possible inherent malfunction. The Burning Question arises as this thread is titled: CAP: Keep or Delete? THIS one, as a '68 WILL be subject to emissions testing, so IFF this setup can be made serviceable, QUICKLY and easily, then I'm all for keeping it. But I priced this valve, or the only one I could find, and I don't care for THAT at all!

I have PLENTY of new goodies I COULD install to this motor instead. Would THIS be the Best Option, with the Fart Sniffers after this engines excretia...?
 
I doubt that CAP valve would help significantly in lowering emissions on a smog check test. The smog check standards are probably set pretty high for older vehicles so they are not obviously running around with misfiring or non-firing cylinders primarily. The CAP valve was used primarily to help lower HC emissions during decelerations on new vehicles that had to meet comparatively more strict emission standards than on today's smog checks. If your car runs smoothly (and not too rich of a fuel/air mixture) and the engine is in good shape, you would probably pass relatively easily without the CAP valve.
 
Even with a sniffer, back in about 1968 or so, the Stromberg on our '66 Newport could be adjusted to the 14.2 idle AFR spec, so getting there should be a real issue, if needed. The key component was the slightly-retarded ign base timing. According to most of what I've read, the only dist advance curve alterations were in the sub-2000rpm range, with the total advance still being about what it used to be as there were no WOT emissions specs.

Make sure the engine runs cleanly and is not using oil and I suspect you might well be good.

Glad things are progressing!
CBODY67
 
I had the system on a '66 car (first year of CAP in California), so the below is assuming it is relatively unchanged for '68.

CAP system is both ignition system and a different carburetor (leaner idle and transition area I believe). There is a Tech bulletin and master-tech video about it.
Since it does not look like you have the original carb (?), you do not have a complete CAP system anyway.

The valve makes sure the distributor gets full manifold vacuum during engine braking. So no real use for it unless your car is tested during engine braking. As far as I have read, the valve was omitted on automatic transmission cars (and continued on manuals) after a few years, as they do not engine brake a lot and therefore were within emission specs without the valve.

I started out with the original CAP distributor. For a '66 is was supposed to have an initial timing of 5° ADC. This made the car start very poorly and a have a sad idle. If I set the initial timing to 12.5° BTC (as the cars without CAP per FSM), the car started and idled great, but it pinged at cruise. I think because the CAP distributor advances a lot. As CBODY67 wrote total advance is about the same, so from coming from 5° ATC it advances 17.5° more than a standard distributor.
Eventually I changed to the electronic conversion kit from Rick Ehrenberg.

The CAP distributors have a non-adjustable vacuum canister with a round "protrusion" in stead of a HEX. I can't make up from the picture if yours is HEX or round.
Maybe you do not even have the CAP distributor? You can check the part number and if it still has a green tag. Mine had green clips to hold the rotor cap.
And of course you can use your timing light to check how and how much it advances.
 
All,

Thanks for your input. When I get the car tomorrow, I'll begin my tests and repairs/upgrades ASAP then. I reckon I'll remove the CAP valve, probably install that lovely rebuilt distributor I got from the Estimable Halifaxhops months ago, a new coil and my Stromberg carb, check the plugs and fresh them up if needed, THEN take it through Emissions and PRAY!

I recall my '68 Disgustang w a 351 Cleveland fitted with a 600 cfm Edelbrock Performer did well enough with emissions. Still HATE State meddling in my life, despite the putative "Summum Bonum" etc....
 
All,

Thanks for your input. When I get the car tomorrow, I'll begin my tests and repairs/upgrades ASAP then. I reckon I'll remove the CAP valve, probably install that lovely rebuilt distributor I got from the Estimable Halifaxhops months ago, a new coil and my Stromberg carb, check the plugs and fresh them up if needed, THEN take it through Emissions and PRAY!

I recall my '68 Disgustang w a 351 Cleveland fitted with a 600 cfm Edelbrock Performer did well enough with emissions. Still HATE State meddling in my life, despite the putative "Summum Bonum" etc....

You could move from Tucson to California where there are no smog check tests for vehicles built before 1975. They are much more enlightened on the issue than other states since the California Air Resources Board & Bureau of Automotive Repair which run the state's Smog Check program work with facts and statistics rather than old school approaches that yield nothing more than headaches in some other states. California also developed the OBD II "check engine light" regulation on its own with no assistance from the federal EPA and that system is now used on all cars nationwide and in most countries around the world. Cars newer than about model year 2000 are "smog checked" in California only by checking the OBDII system monitor for the presence of fault codes, which if present, must be corrected to pass. The OBD II system is quicker to detect faults in emission components earlier than a dynamometer smog check test could find problems with emission performance and also helps technicians that have to repair the systems to pass by using fault codes to actually detect which component is faulty in todays complex electronically controlled vehicles.
 
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You could move from Tucson to California where there are no smog check tests for vehicles built before 1975. They are much more enlightened on the issue than other states since the California Air Resources Board & Bureau of Automotive Repair which run the state's Smog Check program work with facts and statistics rather than old school approaches that yield nothing more than headaches in some other states. California also developed the OBD II "check engine light" regulation on its own with no assistance from the federal EPA and that system is now used on all cars nationwide and in most countries around the world. Cars newer than about model year 2000 are "smog checked" in California only by checking the OBDII system monitor for the presence of fault codes, which if present, must be corrected to pass. The OBD II system is quicker to detect faults in emission components earlier than a dynamometer smog check test could find problems with emission performance and also helps technicians that have to repair the systems to pass by using fault codes to actually detect which component is faulty in todays complex electronically controlled vehicles.

I agree that the OBDII system is far superior to the old dyno tests. Oregon gave up on that type of testing because the dyno equipment could not handle the volume of testing without constant repair. The down side to the OBDII system is that a dirty ground cable will cause the PCM to go temporarily insane and start generating false codes. A good test for this condition is if fault codes are generated for equipment the vehicle does not have. On Chrysler products, a common false code is a left or right oxygen sensor fault on four cylinder engines that have only one oxygen sensor.

Depending on how long it takes to generate a fault code, numerous faulty vehicles have passed inspection by using a hand held scanner and deleting the code prior to the test. Folks attach the scanner outside of the test center, clear the code and have the vehicle tested before the code regenerates.

Dave
 
Greetings Esteemed Moparians!

While perusing the engine compartment pic for the Next Newport, I noticed the distributor control valve in back of the Carter B & B carb that indicates a CAP setup.

View attachment 486935

The current owner complained of the carburetor malfunctioning, but I now suspect maladjustment as much as possible inherent malfunction. The Burning Question arises as this thread is titled: CAP: Keep or Delete? THIS one, as a '68 WILL be subject to emissions testing, so IFF this setup can be made serviceable, QUICKLY and easily, then I'm all for keeping it. But I priced this valve, or the only one I could find, and I don't care for THAT at all!

I have PLENTY of new goodies I COULD install to this motor instead. Would THIS be the Best Option, with the Fart Sniffers after this engines excretia...?

The fart sniffer will only detect hydrocarbons, carbon monoxide etc. It does not test the installed equipment, so you can safely get rid of the distributor delay and it will not make any difference on the sniff test. A lot of them plugged up with use and disabled the vacuum advance to where the vehicle got poor mileage and ran like crap. So much for clean air engineering.

Dave
 
You could move from Tucson to California where there are no smog check tests for vehicles built before 1975. They are much more enlightened on the issue than other states since the California Air Resources Board & Bureau of Automotive Repair which run the state's Smog Check program work with facts and statistics rather than old school approaches that yield nothing more than headaches in some other states. California also developed the OBD II "check engine light" regulation on its own with no assistance from the federal EPA and that system is now used on all cars nationwide and in most countries around the world. Cars newer than about model year 2000 are "smog checked" in California only by checking the OBDII system monitor for the presence of fault codes, which if present, must be corrected to pass. The OBD II system is quicker to detect faults in emission components earlier than a dynamometer smog check test could find problems with emission performance and also helps technicians that have to repair the systems to pass by using fault codes to actually detect which component is faulty in todays complex electronically controlled vehicles.

Cal simply has too many people now for my liking, and the cost of living there guarantees we'd remain homeless. If it weren't for my spawn, I'd like to find some dusty little shitsplat town in this State or New Mexico to cop my Final Fade in, draw Social Security and mummify. But, I owe it to my children to have access to resources that only civilization furnishes, so we stay and hunker here.
 
The fart sniffer will only detect hydrocarbons, carbon monoxide etc. It does not test the installed equipment, so you can safely get rid of the distributor delay and it will not make any difference on the sniff test. A lot of them plugged up with use and disabled the vacuum advance to where the vehicle got poor mileage and ran like crap. So much for clean air engineering.

Dave

Thanks Dave! I thought that would be so. I think the CAP just relied on that fact of greater vacuum advance variation, which, as you wrote, didn't work too well at all after a bit of wear. OK, OUT with the CAP, and IN with the '66 383 fuel system and ignition goods! I have THAT set up sweet and sure.
 
Even with a sniffer, back in about 1968 or so, the Stromberg on our '66 Newport could be adjusted to the 14.2 idle AFR spec, so getting there should be a real issue, if needed. The key component was the slightly-retarded ign base timing. According to most of what I've read, the only dist advance curve alterations were in the sub-2000rpm range, with the total advance still being about what it used to be as there were no WOT emissions specs.

Make sure the engine runs cleanly and is not using oil and I suspect you might well be good.

Glad things are progressing!
CBODY67

Right on! I reckon I'll make this a regular setup instead of diddling w the CAP stuff, especially if its giving trouble as I was told it does when starting. I MIGHT just yank that distributor control valve and dial the timing to -12.5 degrees right off, then put it through the paces. Compression check will likely be this Saturday, as I'm apt to be busy Friday.

Stay Tuned!
 
If you remove the distributor control valve, the lower rpm centrifugal advance curve is a bit slower than normal, but it pretty much back to normal past 2000rpm. SO, you'll need a normal (non-CAP spec) distributor BEFORE you alter the base timing. The CAP distributor and the control valve and the timing setting are something of a matched set. Check out the tune-up and distributor specs in the FSM for CAP and Federal-spec engines, for good measure.

Enjoy!
CBODY67
 
Depending on how long it takes to generate a fault code, numerous faulty vehicles have passed inspection by using a hand held scanner and deleting the code prior to the test. Folks attach the scanner outside of the test center, clear the code and have the vehicle tested before the code regenerates.

Dave

That will not work! That was thought about during development of the 150 page regulation for OBD II and clearing the fault codes before inspection will just yield a "not ready" code for going through vehicle inspection. You must drive the vehicle enough even after a repair of a component to be able to complete the monitor for it to ensure the component has been really fixed before reinspection.
 
That will not work! That was thought about during development of the 150 page regulation for OBD II and clearing the fault codes before inspection will just yield a "not ready" code for going through vehicle inspection. You must drive the vehicle enough even after a repair of a component to be able to complete the monitor for it to ensure the component has been really fixed before reinspection.

That is true if the battery cable is unhooked and all the information on the computer is cleared. Most of the individual codes will test ready shortly after the vehicle is started. If an individual sensor is not in contact with the computer it will trigger an immediate code. Codes like a vacuum leak in the evap system take time to register and will test ready initially. It depends on which codes and the severity of the defect.

Dave
 
You could move from Tucson to California where there are no smog check tests for vehicles built before 1975. They are much more enlightened on the issue than other states since the California Air Resources Board & Bureau of Automotive Repair which run the state's Smog Check program work with facts and statistics rather than old school approaches that yield nothing more than headaches in some other states. California also developed the OBD II "check engine light" regulation on its own with no assistance from the federal EPA and that system is now used on all cars nationwide and in most countries around the world. Cars newer than about model year 2000 are "smog checked" in California only by checking the OBDII system monitor for the presence of fault codes, which if present, must be corrected to pass. The OBD II system is quicker to detect faults in emission components earlier than a dynamometer smog check test could find problems with emission performance and also helps technicians that have to repair the systems to pass by using fault codes to actually detect which component is faulty in todays complex electronically controlled vehicles.

I wonder if the California Air Resources Board has found like other entities, that as a department, with everything that comes with it's existence that they are creating more emissions by simply existing than they are taking off the road.

I have heard about this a few times over the years. With Washington State coming to mind in particular. I have read that since the oldest cars on the road in any meaningful numbers are no more than 20-25 years old which are fully emission control vehicles. This is resulting in a finite percentage of vehicles getting a repair before registration requirement.

As an aside this marks the first time in my life that I have heard the suggestion that anybody move from anywhere much less Arizona to California for increased liberty. The light bulb should come on if anybody finds that to be their situation.

Second aside, strangely, just 5 minutes ago I found a phenomenal bonus box of my stuff that my wife must have thrown together and put in the garage as she sometimes does. Amongst the knives, usb chargers (new 2 of them), fineline masking tape and even a Dirty Mary Crazy Larry match Box Charger! Was an OBD II code reader. Something that I know is not mine. She has the only car new enough to scan I think 2011. Probably her Dads.
I literally sat down thinking OBD II reader? Then read this. Weird.
 
That is true if the battery cable is unhooked and all the information on the computer is cleared. Most of the individual codes will test ready shortly after the vehicle is started. If an individual sensor is not in contact with the computer it will trigger an immediate code. Codes like a vacuum leak in the evap system take time to register and will test ready initially. It depends on which codes and the severity of the defect.

Dave


If all else fails, the quick test for for mopar readiness is: Turn the key on, (do not crank or start) in about 10 seconds if the check light starts to flash and after a time illuminates to a steady glow, the system is not ready to test due to stored codes or a lack of information. If the check engine light stays on and does not flash, the system is ready to test.

Dave
 
That will not work! That was thought about during development of the 150 page regulation for OBD II and clearing the fault codes before inspection will just yield a "not ready" code for going through vehicle inspection. You must drive the vehicle enough even after a repair of a component to be able to complete the monitor for it to ensure the component has been really fixed before reinspection.
While I really know nothing of the OBD II system, the New York State system of annual inspection requires that most(?) of the operating codes will need the car to be driven after clearing the codes.

When my oldest son worked at the Ford store as a service writer, one of his duties was to drive customer's cars that had codes cleared. He had a route that he drove that worked out that was just enough to get the car through the NYS test, which included hooking the OBDII port to a state operated system.

Funny story... When the state first got the system up and running, a couple of the shops have had this happen. They'd hook the car up and suddenly get a phone call that went something like this "Is the owner of that car there?". "Yes...Why?" "This is the NY State Police, stall him a little if you can, we'll be right there". and the next thing you knew, the State Troopers were there to arrest the car owner. Seems the system alerted them to someone they were looking for.

I haven't heard one of those stories in a while, so I wonder if that is no longer true... It would seem to put everyone in the shop in harm's way if things went bad.
 
Set it up however you want. You can’t drive it on the rollers anymore and the goon doing that is paid to make you fail. I used to always limit my carbs so floored it could not produce more than 2600 rpm. I believe 2400 was the test rpm. We’d disconnect and wire shut the secondaries and use a special set of metering rods that guaranteed a passing grade. For our multi carb stuff it was easier to pull the intake and go thru with a single 4v. Once they kept you in the booth during testing all feather footing was effectively banned. You’re limited on what you can do with that two barrel but I’d still set it up so that WOT cannot be achieved. You can put it back to normal in the parking lot across the street. Remember it’s about revenue not clean air. They are trying to fail you...

And it’s true. No smog has been the best thing about moving to California from Arizona (California jr) except for maybe the weather the beach being closer to Carmel and even more car shows to go to than in Az. And Az has a lot of car shows.
 
67 and newer cars in Arizona do have to pass an emission test. Years ago I heard that Jan Brewer, a former Governor approved moving the year required up to I think 1976. Supposedly it was sent to the Feds for approval but that approval never happened. I guess I should start contacting some of our usless politicians in Washington and ask WTF is happening with it?
 
67 and newer cars in Arizona do have to pass an emission test. Years ago I heard that Jan Brewer, a former Governor approved moving the year required up to I think 1976. Supposedly it was sent to the Feds for approval but that approval never happened. I guess I should start contacting some of our useless politicians in Washington and ask WTF is happening with it?

I doubt there has been anyone at the federal EPA that knows anything about OBD II for at least 10 years and only a couple even back then knew anything about it. With the last administration, the only ones that did know anything all quit or went for early retirement. EPA really had nothing to do with the whole OBD system and pretty much deferred to California to set future vehicle emission standards and to develop and implement OBD II since the early 1980s. The federal EPA is also the agency that put ethanol in gasoline when California was staunchly opposed to it. There was a meeting back then with EPA over the subject and it was the most intense meeting ever between the two agencies. People got up and left in the middle of the meeting shouting at each other and it was bad. The corn growers and big Ag got to EPA and we are still suffering, especially with our older cars, over that stupid decision that was made without any good data.

Today's vehicles are pretty complex but also very durable, they have flawless driveability and still perform amazingly well while also meeting very stringent emission standards - even the Hellcat Redeyes. When they do break, it wouldn't be fun to try to fix any of them without an OBD system to help lead the way. Under the hood, every car built in the U.S. has California's fingerprints all over them, like it or not.
 
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