Points ignition? Any advantages?

[cjperformance]

Don't really need nostalgia. The points I had in my Mgb I just adjusted with a dwell meter. Much easier/simpler. I was just curious from a performance standpoint if they had any desirable benefit. Looks like I'm going solid state.

Thanks.

If the vehicle already has points, the best thing you can do is make it so those points do not NEED to pass any electrical current and simply act as a switch, using a newer ignition box type ignition.

We do it all the time with nostalgia type cars and use a Ford "Thick Film ignition", (TFI 35368 ACCEL), from a 94 mustang using the points simply as a trigger which will connect to the spout terminal.
That ignition is small and fits inside most air cleaners.

Walter, great idea, Ive never used a TFI module switched by points, interesting. Would you mind posting here or PM'ing me a wiring diagram of how you connect this setup and what ignition coil you use?
Thankyou,

[DaveMcLain]

Walter,
To state the ****ing obvious, if old cars do not have point conversion kits, then...er...you are stuck with [1] factory points ign [2] cobbling something together to convert to elec ign [3] using a points life extender. Not short 'sided' at all. Over the years I have converted many points cars to various elec ign systems. One 440 Mopar around here that I modified for elec ign has a Pontiac points dist in it, a Chrysler mag trigger & 4 pin Bosch module [ similar to HEI, Bosch switches more current ].
Back in the mid 60s before elec igns were available, I was using a points extender that used an SCR, a diode & two resistors; cost less than $10 in todays dollars. The SCR switched the heavy coil current.

A good HEI style ign delivers about twice as much energy to the spark as a points ign because points are limited by the amount of current they can switch. That's why HEI igns can run 0.060"plug gaps, not 0.035" like points.
Points are always going to have three limitations that elec igns do not have:
[1] Point contact pitting
[2] Rubbing block wear
[3] Limited spark energy due to current switching limitations of point contacts.

To me, it is a no brainer......

The small, simple FORD divorced TFI electronic ignition module has big power output energy and does everything else you mention EXCEPT, unlike those others, it can be triggered with the original older vehicle points ... which will carry NO electrical current at all.

And believe it or not the points not carrying any current at all can be a problem. Back a long time ago my Dad was given several electronic ignition boxes that I think were made by Motorola. They were used but functioned perfectly. Someone he knew had tried them on a fleet of trucks that he maintained in St Louis. They were short haul delivery trucks and the boxes were triggered by the points but the box did all the work so in other words the points had to deal with zero current. At first all was well but then suddenly one day a truck wouldn't start. They thought something happened to the box but as it turned out the points would no longer trigger the electronics because they had oxidized. A very quick cleaning and they were back in service. It was enough of a problem throughout the fleet that they found that they were better off using a high quality set of points by themselves without the box and changing them on a regular schedule. I guess the points needed a little bit of current across them to keep them clean.

[Zmechanic]

And believe it or not the points not carrying any current at all can be a problem. Back a long time ago my Dad was given several electronic ignition boxes that I think were made by Motorola. They were used but functioned perfectly. Someone he knew had tried them on a fleet of trucks that he maintained in St Louis. They were short haul delivery trucks and the boxes were triggered by the points but the box did all the work so in other words the points had to deal with zero current. At first all was well but then suddenly one day a truck wouldn't start. They thought something happened to the box but as it turned out the points would no longer trigger the electronics because they had oxidized. A very quick cleaning and they were back in service. It was enough of a problem throughout the fleet that they found that they were better off using a high quality set of points by themselves without the box and changing them on a regular schedule. I guess the points needed a little bit of current across them to keep them clean.

Yes, this absolutely true. This also applies to relays as well, since their function is very similar. For relays designed for certain low current applications, they list a "minimum" load, to ensure enough minute arcing to keep the contacts from oxidizing over. Also, every time the contacts touch and pull apart, there is a chance of microscopic metal transfer. Opening/Closing under low/no load can exacerbate this to the point the resistance begins to shoot up.

[Truckedup]

The small, simple FORD divorced TFI electronic ignition module has big power output energy and does everything else you mention EXCEPT, unlike those others, it can be triggered with the original older vehicle points ... which will carry NO electrical current at all.

You can do the same with a 4 pin GM HEI module.....And it's less expensive ... On a modified vintage GMC 302 inline 6 I used a stock recurved distributor to trigger a multi spark CD ignition...The points gap never seemed to change.The trick is to buy NOS brand name points that last much longer than the often poor quality stuff sold today....We're all supposed to be engine guys on here, a little engine maintenance is good for the soul on a "hot rod"
I still mess with old engines and the ignition issues seem to boil down to poorly made made condensers...There are solid state condenser option...

POINTS will not trigger a 4 pin GM electronic HEI ignition module and any aftermarket multi spark CD ignition certainly is not less expensive.

A lot of regular car enthusiasts do not have the ability, or even the wish, to fabricate a later magnetic impulse or Hall effect distributor or the internals to m work with their early Packard or Nash or Plymouth flathead 6 or their preferred old time nostalgia ride.
It appears that some people have absolutely no clue as to the mindset of these enthusiasts.

This is one of several ways to use a four pin HEI.....It does work.......

[Geoff2]

Excellent point [ pardon the pun ] raised about points oxidisation due to no/insufficient current flow. It is well known in electrical theory that some current flow is desirable to keep switching contacts 'clean'.

[user-23911]

The technical term for it is "contact wetting".
Standard practice in telephone exchanges in days gone by.

You can't have zero current anyway.....you can't trigger anything with zero current. But there's a minimum required.
It's no different really from the voltage/current graph of a semiconductor and the first semiconductor diodes were made out of copper oxide............also used in telephone exchanges before silicon diodes were invented.

[Walter R. Malik]

The small, simple FORD divorced TFI electronic ignition module has big power output energy and does everything else you mention EXCEPT, unlike those others, it can be triggered with the original older vehicle points ... which will carry NO substantial electrical current at all; (just a few millevolts).

A lot of regular car enthusiasts do not have the ability, or even the wish, to fabricate a later magnetic impulse or Hall effect distributor or the internals to m work with their early Packard or Nash or Plymouth flathead 6 or their preferred old time nostalgia ride.
It appears that some people have absolutely no clue as to the mindset of these enthusiasts.

This is one of several ways to use a four pin HEI.....It does work.......

I am going to try that ... do you remove the condenser or leave it connected to the points...?

[modok]

Yes that works but it works backward, it fires when the points close not open, so you will want to re-clock the rotor, and...
It is customary to instead use approx a 40 ohm resistor. This runs enough current through the points to keep them clean.
MSD boxes use 40 ohms, and so did delta before them.
TFI fires "going high", like points do, opposite of the GM , so using the TFI module is a lot easier.

Leave the condenser if you use a 40 ohm pull up resistor, but remove it if you don't.

[jake197000]

you can hide a petronics in there if you get creative.

[engineguyBill]

No, there are no advantages to using point type ignition, over the electronic version. Problem with points is that they tend to bounce at high RPM and if the spring is replaced with a heavier one, then it tends to wear out the rubbing block. The only downside that I have see with electronic ignition was that back in the early 70's GM was using what they referred to as "transistor ignition", which was much like current HEI units. The transistor ignition would not hold up in high summer heat so many dealers in states such as Arizona ordered new cars for their inventory with points type ignition. I bought a new Chevrolet Cheyenne pickup in 1974 (Arizona) that had 454" engine with points-type ignition.

[David Redszus]

Points are little more than a mechanical switch used to fire an induction coil. It is the coil that produces the spark energy. Points, when properly designed and installed are perfectly servicible and were used on F1 cars years ago.

Points with inadequate spring force will bounce at some rpm causing misfires. Worn rubbing blocks (or cam lobes) will alter dwell time and coil charging. And points do need attention due to possible contacts oxidation and pitting.

To overcome these issues, alternate switching was developed, using Hall Effect or magnetic impulse triggers.
They worked fine. But they were still limited to a pre-determined advance curve created by flyweights and springs and sometimes vacuum diaphragms.

The coils had their limits as well. For four and si cylinder engines the coils could deliver sufficient voltage at higher rpm; but not for eight cylinder engines. Alternatives to coils included capacitive discharge systems that used capacitors instead of a coil. They produced very high firing voltages but had limited spark duration.

Advances in engine control systems required an ignition that could be programmed to respond to multiple input parameters. Today a modern engine will make use of a CPU controlled ignition module and multiple coils over plugs.

But without an engine analyzer or engine scope, it would not be possible to determine how well the ignition system is functioning. A modern ignition system will allow a readout of dwell angle anf spark advance under all operating conditions.

But for older, classic cars, a well tested and properly installed set of points is part of vehicle originality.

[Truckedup]

The coils had their limits as well. For four and si cylinder engines the coils could deliver sufficient voltage at higher rpm; but not for eight cylinder engines. Alternatives to coils included capacitive discharge systems that used capacitors instead of a coil. They produced very high firing voltages but had limited spark duration.

CD ignitions I have seen, mostly on bikes, have a coil..I believe it does not function exactly as the coil used in a Kettering ignition but it's still a coil..

[enigma57]

Speaking of coils...... I was digging through my ignition parts earlier today, as I will be running an MSD capacitive discharge box on my 292 inline 6 build. Ditto son's 350 Camaro engine.

In the past, I have run the same oil filled Mallory Voltmaster II coil (#28675) with points and then used it with an MSD 6A ignition box and magnetic pickup type distributor. Worked fine with both.

Looking at the various Mallory Voltmaster coils I have managed to collect over the years, I have several different part numbers on these coils which are marked for 'Electronic Ignition'. I have another that is marked 'CD Ignition' and one that is marked 'Magneto Transformer' (this one has a brown top and black body, all the others are solid black).

So why so many different part numbers and why so many different applications when my original #28675 coil worked fine with points and with a distributor having magnetic pickup. Externally, all these coils are identical except for the ID tag and for the 'Mag Transformer' having a brown top.

Just wondering. Is there a real difference in their internals or were the numerous applications and differing part numbers more of a marketing strategy with the later Voltmaster II coils?



Thanks for any insight on this,

Harry

[gruntguru]

Measure the primary and secondary resistances to give you some feel for what the internal differences might be.

[jake197000]

points fire when they open the time they spend closed is called dwell.its what gives you coil saturation thats also why when you turn the distbibutor the timing changes