Ford DS II ignition upgrades?

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travis
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Ford DS II ignition upgrades?

Post by travis »

How does well does the Duraspark II ignition system work in a mild to medium level performance application? At what point does it become necessary to either upgrade or replace with something better? I’ve got a crane adjustable vacuum advance kit with different springs to modify the advance curve. There seems to be no upgrades available for the ignition module. What about the coil? I’ve got no idea what I can or can’t use.

I really don’t want to “upgrade” to a MSD system, plus I do like the simplicity and easy to find replacement parts of an OEM system. HEI’s are another option but that big ass cap causes fitment issues with everything around it (fuel lines, air cleaners, etc).
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Re: Ford DS II ignition upgrades?

Post by mag2555 »

If you need to make rising HP numbers above 5500 rpm then you have no choice but to ditch that factory system, especially if your running compression ratio's above 11 to 1.
You can cut a man's tongue from his mouth, but that does not mean he’s a liar, it just shows that you fear the truth he might speak about you!
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Re: Ford DS II ignition upgrades?

Post by BobbyB »

Just converted a 1974 duraspark to a HEI using a pertronix module( the one with multiple sparks and rev limiter built in) and tfi coil. My understanding is that if you keep plug gaps at .040 or less you can use the small cap. The engine is a 10.4 to 347 that pulls fine to just over 6000 rpm so far... but it ran fine on the duraspark too. I do think the hei runs better though.
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Re: Ford DS II ignition upgrades?

Post by Walter R. Malik »

travis wrote: Mon Mar 23, 2020 10:58 am How does well does the Duraspark II ignition system work in a mild to medium level performance application? At what point does it become necessary to either upgrade or replace with something better? I’ve got a crane adjustable vacuum advance kit with different springs to modify the advance curve. There seems to be no upgrades available for the ignition module. What about the coil? I’ve got no idea what I can or can’t use.

I really don’t want to “upgrade” to a MSD system, plus I do like the simplicity and easy to find replacement parts of an OEM system. HEI’s are another option but that big ass cap causes fitment issues with everything around it (fuel lines, air cleaners, etc).
Adding a Pertronix "Second Strike" will greatly improve what you already have.
There are many coils which will help but, some will actually hurt performance;
If using a canister type coil, the Pertronix #45011 (oil filled) or #45111 (epoxy filled) work very well in this situation.
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Re: Ford DS II ignition upgrades?

Post by Tuner »

mag2555 wrote: Mon Mar 23, 2020 12:25 pm If you need to make rising HP numbers above 5500 rpm then you have no choice but to ditch that factory system, especially if your running compression ratio's above 11 to 1.
LOL at you kids that apparently never had the pleasure of using points ignition with engines turning considerably more than 5500 RPM.
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Re: Ford DS II ignition upgrades?

Post by ClassAct »

Tuner wrote: Tue Mar 24, 2020 3:37 pm
mag2555 wrote: Mon Mar 23, 2020 12:25 pm If you need to make rising HP numbers above 5500 rpm then you have no choice but to ditch that factory system, especially if your running compression ratio's above 11 to 1.
LOL at you kids that apparently never had the pleasure of using points ignition with engines turning considerably more than 5500 RPM.


LOL...nothing ever made power above 5500 until 1972 when electronic ignitions came out. NOT!!!!! How did anything ever run before then LOL?????
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Re: Ford DS II ignition upgrades?

Post by Tuner »

427 435hp tach, 6500 RPM redline, single point Delco-Remy ignition. D112-P Delco-Remy points, 8000+ no sweat, no dwell loss or point bounce when used in a properly prepared distributor.

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Re: Ford DS II ignition upgrades?

Post by Pete1 »

"nothing ever made power above 5500 until 1972"

Oh???
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Re: Ford DS II ignition upgrades?

Post by ClassAct »

Pete1 wrote: Wed Mar 25, 2020 12:12 am "nothing ever made power above 5500 until 1972"

Oh???

That was my sarcasm. It didn't translate well into typewritten words!
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Re: Ford DS II ignition upgrades?

Post by mag2555 »

Sorry, but I am well into my 60s and I recall all too well stuffing a section of windshield washer tubing behind the outer point arm to get more rpm out of the motor without breaking up !

Stuff in 14 to 1 compression in to any motor running on a stock coil fed point system tacking between 5500 and 6000 rpm which is where things start to go off the rails and then come back and post up how much you like it!!
You can cut a man's tongue from his mouth, but that does not mean he’s a liar, it just shows that you fear the truth he might speak about you!
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Re: Ford DS II ignition upgrades?

Post by Tuner »

mag2555 wrote: Wed Mar 25, 2020 6:37 am Sorry, but I am well into my 60s and I recall all too well stuffing a section of windshield washer tubing behind the outer point arm to get more rpm out of the motor without breaking up !

Stuff in 14 to 1 compression in to any motor running on a stock coil fed point system tacking between 5500 and 6000 rpm which is where things start to go off the rails and then come back and post up how much you like it!!
Sorry you had a tough time. Most of us fortunate to have a distributor machine and use it nearly every day for the last 50+ years know the hose behind the point arm trick was a magazine lore trick that doesn't work.

The magazines did the best they could to convince everyone anything to do with genuine OE parts was worse than the swine flu, when in fact, the OE parts were vastly superior than aftermarket junk 99% of the time.

In the case of ignition points, this is exactly the case, Delco D-112P points in a good tight distributor with the right breaker cam will easily run over 8000 RPM with rock solid dwell and timing.

The Corvette dual point and Fuel Injection distributors with the solid mounted breaker plate would function well over 9000 with Mallory "X" heavy spring points.

Regular Mallory 102 points were almost as good as the Delco D-112P. The "X" points with the heavier spring need more regular attention to the dwell adjustment because of rubbing block wear and general mechanical settling of the rubbing parts.

The feature that gave the Delco and Mallory points good high RPM performance was they have lighter weight breaker arms and the lighter oscillating parts don't need crazy high spring pressure to function well. Same reason Titanium valves don't need as much spring pressure as steel valves require to run the same high RPM.

Other brands of "heavy duty" or special "high RPM" points have an extremely heavy "heavy duty" breaker arm that by its extra weight requires more spring pressure and the combination of extra weight and higher spring pressure requires more force to function and more force causes more flexing and vibration of the breaker plate, so the extra weight arm and stronger spring are actually less desirable and counter productive.

The difference in sound of a distributor with the Delco D112P points with 27oz spring pressure compared to Accel points with the heavy breaker arm and 40oz spring pressure is dramatic. The Accel points have a harsh raggedy buzzing sound and the Delco points just make a soft whir. You don't have to be a rocket surgeon to realize the extra noise isn't anything good.
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Re: Ford DS II ignition upgrades?

Post by BobbyB »

What about Ford stuff? The OP is asking about Ford stuff. Any recommendations for fords?

Hey, while you are at it, why didn’t a 289 high performance have vacuum advance?
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Re: Ford DS II ignition upgrades?

Post by Paul Kane »

travis wrote: Mon Mar 23, 2020 10:58 am How does well does the Duraspark II ignition system work in a mild to medium level performance application? At what point does it become necessary to either upgrade or replace with something better? I’ve got a crane adjustable vacuum advance kit with different springs to modify the advance curve. There seems to be no upgrades available for the ignition module. What about the coil? I’ve got no idea what I can or can’t use.

I really don’t want to “upgrade” to a MSD system, plus I do like the simplicity and easy to find replacement parts of an OEM system. HEI’s are another option but that big ass cap causes fitment issues with everything around it (fuel lines, air cleaners, etc).
MSD’s reluctor and magnetic pickup coil are, in fact, the same FoMoCo reluctor and pickup coil as in your factory Dura-Spark distributor. This is probably why MSD offers instructions to wire a Dura-Spark box to their MSD model distributor and/or an MSD box to a Dura-Spark dizzy. So unless you need to make use of a rev limiter chip or any other feature found only on the MSD stuff, don’t waste your money when a remanufactured FoMoCo Dura-Spark unit with a recurve kit will do. Not saying this is the greatest they can manage but I’ve know Dura-Spark ignitions to support 7000 rpm, low 7-second quarter-mile times, and blown alcohol engines supporting 4-figure HP.
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Re: Ford DS II ignition upgrades?

Post by travis »

I’m going to try just a coil upgrade first and see how that does, and go from there.

I do have a question about coils though. How do you determine what coils are compatible with your ignition system? Do you need to match the ohms of the stock coil semi-closely to an aftermarket coil. If you use one with considerably lower resistance, do you need to add a ballast resistor to get the total resistance closer to stock?
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Re: Ford DS II ignition upgrades?

Post by Walter R. Malik »

travis wrote: Thu Mar 26, 2020 8:50 am I’m going to try just a coil upgrade first and see how that does, and go from there.

I do have a question about coils though. How do you determine what coils are compatible with your ignition system? Do you need to match the ohms of the stock coil semi-closely to an aftermarket coil. If you use one with considerably lower resistance, do you need to add a ballast resistor to get the total resistance closer to stock?
A Dura-Spark system already has a resistor or resistance wire in the vehicle system and by-passes it for starting only.
If it is wired separately without the vehicle system then be sure to include an appropriate resistor for that coil used.

You really can only take what manufacturers say will work with a grain of salt;
the only real way to find what works well or not is "trial & error" ... been there.
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