Thanks for all the responses guys-

[Michael W.]

and not to beat this to death, but other than the high rpm advantages pointed out by Duke and Joe, I still see no basis or explanation for the supposed improvements for starting, idle or normal driving.

I had expected Jack H to jump in but rarely understand more than half what he says anyway (joke).

[Joe L.]

Re: Thanks for all the responses guys-

Mike-----

One thing to think about is this: the switch to electronic ignition systems in the mid 70s was certainly not influenced by a desire for better high RPM performance on the part of the car manufacturers. High RPM pereformance is, for all practical purposes, a non-issue for about 99% of the cars produced. In the mid- 70's when these systems were initially installed, high RPM performance was probably not an issue for just about 100% of the cars manufactured.

Also, I don't think that it was a cost savings matter, either. I feel quite confident that electronic ignition was a more expensive system to install than points ignition. Especially, since all of the tooling costs for points distributors had been pretty much amortized by the time that electronic ignition was introduced.

So, without even getting into the complex technicalities of the matter, one could infer from the above that these systems must have had other benefits in order for the car makers to start using them. Obviously, emissions may have been one of the reasons. But, better ignition performance for emissions reasons likely will have other benefits. Easier starting, better idle, and lower exhaust fumes, as some have reported when using Breakerless, might just be some of the "side-benefits" which electronic ignitions produced.

[Michael W.]

Re: Thanks for all the responses guys-

Joe,

We're now getting into two different issues- electronic points triggering a stock coil and wires, versus a complete HEI (high energy ignition) system. I have no qualms about the HEI system and it's benefits, but HEI as installed in a '75 and up Corvette is a very different animal altogether. Dropping an electonic set of points into a distributor does not equate to an HEI system.

[Mike McKown]

Re: Thanks for all the responses guys-

At the risk of being voted wrong, breakerless ignitions were introduced to deliver a much hotter spark to the plugs to fire the leaner fuel mixtures that came to be in the 70's. The hotter spark allowed the plug gaps to go to 45-60 instead of 32-35. The ignition coil voltage was almost doubled. I think something was said about points not being reliable under these conditions.

[Clem Z.]

the big advantage is that the timing does not

change with time so the emissions stay fixed for the manufactures length of warranty on the emission system. it also alows a larger plug gap which allows for more effectent combustion. there may even be some HP gain from the larger plug gap. back years ago i built and installed on my race cars a "dwell extender" which closed the points electronically before they closed mechanically there for increasing the coil dwell time make for a hotter spark. we could tell if the "dwell externder " went bad because the engine would not RPM like before

[Jack H.]

Jumping in...

Others were doing a fine job with their explanations and didn't appear that I needed to add text, because you say you don't understand half of what I say. But, here's a few comments:

(1) I addressed the Breakerless SE system which is specific to one manufacturer.

(2) Some of the folow-on thread comments have used the term 'breakerless' as an omnibus or generic to read on other systems (Pertronix, Mallory, Etc.).

(3) True most comparisons ARE made with existing distributor (including wear and slop) vs. a 'printed' distributor with fresh new points and condensor. But, that's often a real life situation since the 'drop-in' SS ignition modules are almost totally insensitive to shaft wobble that would produce erratic dwell in a conventional electro-mechanical ignition system.

(4) With a conventional ignition system, matching the points and condensor has long been known to be a racer's trick (view the wear characteristics of the points and hand select a condensor 'match' that system's specific ressonance). In an electronic system, the dwell is dead nuts on, independent of point contact resistance and specific condensor capacitance.

(5) Other than point bounce/float that can occur at high RPM, specific dwell changes modestly with RPM in a conventional ignition since contact closure time IS a function of engine RPM. The Breakerless SE module is 'smart'...it knows what RPM the distributor is turning at and dynamically fine tunes its dwell to compensate.

(6) Since the primary ignition waveform to the coil is 'manufactured' by the electronic ignition module vs. being an analog byproduct of the mechanical rotation of the distributor shaft, it can guarantee a uniform input waveform to the coil primary independent of shaft rotation specifics, spring constant of the points, surface ohmic contact profile (temperature dependent), and specific condensor capacitance profile.

All of the above are technical reasons for manufacture claims of smoother idling, better performance across the engine's dynamic RPM range, Etc.

So, there are some of the reasons

[Joe L.]

Re: Thanks for all the responses guys-

Mike------

Yes, what you mention is exactly correct. Electronic ignition is not necessarily the same as HEI. Certainly, electronic ignition, alone, will not produce all the benefits of HEI.

Some time ago I had a fairly long converstion with Dave Fiedler of TI Specialties about Breakerless ignition. Dave is a big fan of the Breakerless system and does distributor rebuilds/restoration using this conversion. Dave says that with the Breakerless system, the voltage delivered to the spark plugs is about the same as with the old TI systems. So, with the simple addition of Breakerless, one can achieve just about all the benefits of TI.

Also, in conjunction with a Breakerless (or other) electronic ignition system, one can add a higher output coil. Some of these are about the same size and configuration as stock, so it's a simple, quick bolt-on. Both the Breakerless and coil are easily removed and replaced for judging in about 10 minutes, so even "judged" cars can enjoy all the benefits of electronic ignition very easily except for the few hours they spend on the judging field.

[Doug Flaten]

Re: Thanks for all the responses guys-

I went about it backwards on my cars. I installed MSD ignition boxes on my Vette and Mustang triggering both with points. For some reason the Mustang did not run well triggering it with points. Although the points were not pitted or burned, I would replace the points and condenser in less than 200 miles. It would run fine for a while and then the ignition would break up and lose power. Once I installed a Petronix ignition, the car idled better and pulled to a higher rpm (sounds more impressive than it is, it has an inline 6 cyl that doesn't exacltly scream). I was also able to advance the timing more with the electronic ignition vs the points before pinging started, which yielded more power. I figured it had something to do with a more accurate signal. In my mind there should be a better spark with the electronic ignition. Although they are both switches, the electronic switch opens relatively instantaneous when compared to points that open through a transitional period riding up along a cammed surface. Energy is lost as the arc forms. A "loss" of ignition energy creates burning or pitting irregularities on the points surfaces associated with normal wear.