Troubleshooting Duraspark Install

Hello all,

I'm looking for some suggestions with troubleshooting a new duraspark II installation.

I have a 1965 Mustang with a stock 200, and I have recently upgraded to a duraspark II distributor. The distributor, module and plug wires are all straight from the local parts store. I didn't have any luck locating a junkyard donor so I splurged and bought the American autowire harness. I kept the Autolite 1100 and just plugged the vacuum port. I was planning on running the distributor with manifold vacuum until everything is up and running as I'm a pretty big fan of changing 1 thing at a time until everything is working.

I managed to get it running well enough to break in the distributor gear but I can not get the engine to idle below 1500 rpm. It will run as long as I keep the revs up but as soon as I try to lower the idle speed the engine stalls.

I've checked the electrical setup with the duraspark and everything seems to be functioning properly. The engine ran reasonably well before I upgraded the distributor so I'm trying to figure out what I did when I changed out the distributor.

Any suggestions of things I should be checking on to find the source of the problem would be greatly appreciated.

Thanks
Jim

Jim, welcome aboard. First of all what are all the specs on your engine, trans & differential??
If you purchased a distributor from a parts store I will guarantee you that it is not setup for your engine.
Lets have some info. Compression ratio, cranking compression, camshaft, stall speed if a C4 trans. Carburation, exhaust & any other details.
Glad to help, but I need more information. Bill

I have not touched the rest of the engine. As far as I know the compression ratio, and cam shaft are stock. The transmission is a 3 speed manual (2.77) . And as I mentioned in the original post the carb is the 1100 with the SCV and a plugged vacuum port.

I do realise that the distributor has not been tuned to my engine but I was under the impression that for a basically stock engine such as mine the duraspark II would be a big improvement in drivability over the stock LOM distributor that I removed.

As I said I'm a one thing at a time kinda guy. I wanted to get it up and running before messing with something else so that I don't confuse the issue.

I like ur reasoning (C quote in my sig). I'm wondering if this is an exception…a '65 carb (SCV) and a DSII (later, ie 70s) no LOM may not B compatable w/1 another. Our site has a great explination of the carb/dizzy 'feedback system'. It's been provided by Perry, our site's admin, on each Index Page under CI Archive. A quick read on this topic might lend some understanding?
Keep talkin! Let us know…

BTW: thanks for the parts referral -
"...bought the American autowire harness…"

Jim, what is your initial advance set at? If you rev the engine do you see the timing mark advance?
What ignition box are you running?

+1
It's got to be a timing issue if nothing else changed and the vacuum port on the carb is plugged? Do you have the distributor hooked to manifold vacuum or just don't have the vacuum advance hooked up?

Seth, he stated that he has not connected the vacuum.
If he has the Ford DS11 module I wonder it he connected the white retard wire to a full hot or ???? Need feedback from Jim.
The ohm reading of the DS11 pickup coil is 400-800 ohms. They normally check out close the high 5's or low 6's.
I deal with these Cardone remans & they all are just suitable to get the engine started.
I recurve them all the time.
The DS11 distributor from Performance Distributors with the full length bushing I have had several of them where the bushing was not tight enough in the housing & moved causing problems. The cost they get is way to high & the curve is not correct.
Their DUI is full of problems.
Most of their other products are very good.
I can get a real HEI made for the small six & does not have the problems the DUI has.
Lets see what Jim comes up with.

I'm running the standard ford module and I have checked that when the key is in the run position the white wire is not hot. I have manifold vacuum available to me but currently it is not hooked up as I wanted to get the engine tuned up with a vacuum gauge first.

When I had the engine running last it was a little more than 14 degrees advanced without vacuum advance at an rpm a bit over 1500. I've played with things some trying to get it to lower the idle speed so I'd need to verify where it is right now.

I'm at work right now but will check the resistance across the pickup coil tonight and report back. I hadn't checked to see if the mechanical advance was functioning properly but I'll try to get it running again and check that out as well.

I forgot to mention before but I've verified TDC on the balancer is correct and the little bit I played with the timing on the LOM before I removed it would tend to confirm this. However when I started the car for the first time after installing the DSII the timing was significantly retarded from what I would have expected based on where the rotor was in relation to the #1 plug wire. That is why I checked the white wire already. I thought it might have been seeing 12V.

Resistance across pickup is 600 ohms. Timing at 1500 rpm with no vacuum advance is around 16 degrees.

Do you have a major vacuum leak which supplies air, rather than adjusting the idle speed screw??
Is the choke fast idle screw causing your high isle condition??