Pony Carb and DSII

[jamyers]

any updates?

 

[Explorer]

Don't know crap about the Pony carb or SCV, but every Duraspark I've worked on uses ported vacuum. V8 or I6.

 

[Bradbutlernc]

Well, if youre setting the timing with none of those holes plugged then you have a major vacuum leak and a lean condition will make the motor idle higher than normal. Plug all the holes in the motor, check your choke plate and idle (try giving it a little throttle to get it to start, maybe hold it at 1/8) As long as the choke is good and the idles good then it shouldnt have a problem starting. My guess is when you hook up the dist vacuum youre eliminating the vac leak and its making the car try to idle like its supposed to, which is too low?

 

[burnoutstang1]

Sorry guys, a little blizzard rolled in and prevented me from getting home to check the car out. Planning on spending some time with it this weekend, sun's in the forecast. I'm thinking the idle adjustment screw is set too far out. When I got it running with the new carb I don't believe the hole in the intake manifold was plugged, and I recall pulling out the screw a couple turns. I plan to start it then start to cover the hole while slowing screwing the screw back in. This should lean out the mixture and hopefully keep it running with the hole plugged. From there I'm going to stop the car, hook up the distributor to that hole, and we should be in business. That sound right?

 

[burnoutstang1]

So I had some time to tinker with it today. After playing with both idle screws and getting the vacuum hooked up it's running great! I had to kind of ease the hose on with someone on the accelerator at first, then I got it timed about right, played with the screws, and got it going. Fires right up and has a little more umph at higher RPMs. Thanks for all your help guys!

 

[jamyers]

Yay! Glad it's working better.

 

[burnoutstang1]

Well guys, the plot thickens. I went to take it for a spin tonight after letting it sit for a while and now it won't fire. At first it started strong, I pulled it out, and it started sputtering quickly before it died. Then it refused to fire. Any thoughts? I can't imagine why it would start strong then just die off like that. Suggestions for tomorrow?

 

[mustang6]

Did you pick up this carb used? Maybe this is too basic of a question at this point but if you were paying the big bucks for a new carb why would you not order the 68+ model without the SCV? Is there a possibility you could still exchange it for the non-SCV version?

You can plug the SCV and connect the DSII to manifold vacuum, but it will never be matched up the way they were designed to be matched up. Engines with mis-matched SCV carbs and non-SCV distributors typically never run right under all conditions- you can put enough initial timing in them that they idle fair and accelerate OK, but set up this way they can be hard to start and run hot (overheat, fuel boil, etc). Or you can pull back the initial timing so they start and idle well and don't overheat, but then they always seem to stumble on hard acceleration and get poor fuel mileage.

From the Classic Inlines website:

The Vaporizer is an excellent choice for replacing your old Autolite 1100-1V carb. For stock applications or mild performance engines, the Vaporizer is tough to beat. Dyno test have shown the Vaporizer to increase horse power by as much as 20HP, however one can normally expect to see gains around 10-15 HP in most situations. You can also expect to see an increase in your mileage due to the Annular Fuel Discharge boosters, which atomize the fuel much better than the older carbs, especially at idle and lower rpm's.

As we said earlier, if your planning to keep the stock Load-O-Matic distributor, you need to order the early version (63-67) with the Spark Control Valve. However if your planning to upgrade your ignition system, we recommend ordering the later '68 version , which comes without the SCV. This allows you to use the Duraspark II distributor, the DUI distributor, or another aftermarket distributor such as Mallory.

I think something else is up with the engine dying and refusing to fire though- either no fuel, no spark, or timing slipped significantly.

 

[burnoutstang1]

Yeah I purchased it new and didn't see that note until after it was on the way here. :arg: At any rate I managed to get it running on a consistent basis now. Just had to tweak the timing a little more. Now she runs like a champ and haven't had any newer problems. I've got to lower the idle speed a little, but that's no prob. Thanks for all your help guys!

 

[RyanCorpse]

So wait, lemme get this straight:

The Duraspark II distributor definetely needs a vacuum line connected to it which goes into the PonyCarb Vaporizer year '68 WITHOUT the SCV.

When adjusting the DurasparkII distributor, the distrib's vacuum line needs to be plugged?

 

[Explorer]

So wait, lemme get this straight:

The Duraspark II distributor definetely needs a vacuum line connected to it which goes into the PonyCarb Vaporizer year '68 WITHOUT the SCV.

When adjusting the DurasparkII distributor, the distrib's vacuum line needs to be plugged?

When setting your initial timing it needs disconnected and plugged at carb.