Dual points for performance?

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KenWells

Dual points for performance?

Post by KenWells »

1978 Spider
Since the start set of points are missing along with most of the ancillary pieces to switch from start to run contacts I WAS WONDERING.....

Would it be possible to run both sets of points simultaneously while wired in series for additional coil saturation and hotter spark?
So Cal Mark

Re: Dual points for performance?

Post by So Cal Mark »

yes, that's what most dual points systems are used for
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bradartigue
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Re: Dual points for performance?

Post by bradartigue »

They're 10 degrees apart, so maybe. Get a second coil and bypass the ignition relay. It would be unique for sure, you could get a badge for "dual fire"

Doppio Fuoco
So Cal Mark

Re: Dual points for performance?

Post by So Cal Mark »

you don't use a second coil, the points overlap creates longer duration
KenWells

Works!

Post by KenWells »

Both sets of points wired in series, no ignition relay.
Runs and has good hot spark.

No way for me to really know if the spark is any hotter than when it had single points.
So Cal Mark

Re: Dual points for performance?

Post by So Cal Mark »

it will depend on what the point gap is, longer coil saturation time will create a hotter spark. Do you know what the max output your coil has?
KenWells

Re: Dual points for performance?

Post by KenWells »

So Cal Mark wrote:it will depend on what the point gap is, longer coil saturation time will create a hotter spark. Do you know what the max output your coil has?
Gapped points at .018"
Aftermarket Bosch coil
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bradartigue
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Re: Dual points for performance?

Post by bradartigue »

So Cal Mark wrote:you don't use a second coil, the points overlap creates longer duration
I'm lacking the brains to figure this out. They're 10 degrees apart, not firing at the same time...so you're collapsing the field on the coil twice in succession, 8 times in a revolution instead of 4. It isn't a continuous delivery. Using two coils would do the same time as one - and deliver stronger spark.

No?
So Cal Mark

Re: Dual points for performance?

Post by So Cal Mark »

coil saturation occurs when the points are closed, that's what the dwell reading is. So you don't collapse the field twice, it only happens when both sets of points are open. So even though one set opens, you still have a path to ground through the second set.

As for the points setting, you'd have to compare dwell specs before and after to start to calculate the benefit and look at coil output on a scope
KenWells

Re: Dual points for performance?

Post by KenWells »

So Cal Mark wrote:coil saturation occurs when the points are closed, that's what the dwell reading is. So you don't collapse the field twice, it only happens when both sets of points are open. So even though one set opens, you still have a path to ground through the second set.

As for the points setting, you'd have to compare dwell specs before and after to start to calculate the benefit and look at coil output on a scope

Now what I need that set of tubes in your avatar! :mrgreen:

btw, Carquest points aren't an exact replacement. They will work and are good quality.
fiatfactory
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Re: Dual points for performance?

Post by fiatfactory »

.
Last edited by fiatfactory on Tue Jul 02, 2019 5:06 am, edited 1 time in total.
nothing to see here... move along.
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bradartigue
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Re: Dual points for performance?

Post by bradartigue »

fiatfactory wrote:
bradartigue wrote:
I'm lacking the brains to figure this out. They're 10 degrees apart, not firing at the same time...so you're collapsing the field on the coil twice in succession, 8 times in a revolution instead of 4. It isn't a continuous delivery. Using two coils would do the same time as one - and deliver stronger spark.

No?
no,

if the dwell was 50 degrees with one set of points gapped correctly, then because they are 10 degrees apart the new dwell will be 60 degrees (theoretical numbers)

To run two sets of points and two coils would need a distrbutor cap with two coil posts...

SteveC
Yeah - you're right - you'd need that dual setup like some of the Alfas. I'm not thinking it through...
So Cal Mark

Re: Dual points for performance?

Post by So Cal Mark »

the alfa system is something completely different, dual points overlapping will create a hotter spark but don't expect miracles. The coil is still a limiting factor. I haven't seen any studies on whether coil life is shortened due to running them closer to maximum output all of the time. And of course, points begin wearing as soon as the distributor starts turning, so they are the least accurate method of controlling spark output
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bradartigue
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Re: Dual points for performance?

Post by bradartigue »

So Cal Mark wrote:the alfa system is something completely different, dual points overlapping will create a hotter spark but don't expect miracles. The coil is still a limiting factor. I haven't seen any studies on whether coil life is shortened due to running them closer to maximum output all of the time. And of course, points begin wearing as soon as the distributor starts turning, so they are the least accurate method of controlling spark output
Seems pointless (no pun intended) since electronic systems will achieve and exceed the desired result. This just sounds like an opportunity to either burn up your tach, shock the piss out of yourself, or eat coils up frequently.
KenWells

Re: Dual points for performance?

Post by KenWells »

bradartigue wrote:
So Cal Mark wrote:the alfa system is something completely different, dual points overlapping will create a hotter spark but don't expect miracles. The coil is still a limiting factor. I haven't seen any studies on whether coil life is shortened due to running them closer to maximum output all of the time. And of course, points begin wearing as soon as the distributor starts turning, so they are the least accurate method of controlling spark output
Seems pointless (no pun intended) since electronic systems will achieve and exceed the desired result. This just sounds like an opportunity to either burn up your tach, shock the piss out of yourself, or eat coils up frequently.
Thanks for responding, I didn't shock myself and my tach still works perfectly. When my coil fries I'll let you know. :D

(one in every crowd) :wink:
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