Pertronix I vs. II

[73Manta72gt]

Has anyone used both the ignitor I and ignitor II? Could you notice any difference in performance between them?

Thanks

[Ooooner]

Can't say that I have....

[Paul]

Last time I checked, by calling Bug Stuff, the Ignitor II wasn't available for our cars.

[73Manta72gt]

I think the new one is p/n 91847A, old one is p/n 1847V

[kwilford]

According to the link:
PerTronix - IGNITOR II BOSCH 009 & 050 AFTERMARKET More Details

The Ignitor II has many of the same great feature that the Ignitor has, but its smarter. Ignitor II units sense the coil current level and use a powerful micro controller to adjust the dwell. Variable dwell helps to maintain peak energy throughout the entire RPM range.

Features
Ignitor II systems develop up to 4 times more energy between 3000 and 5000 RPM than standard ignition systems. High RPM performance is improved when used with the Flame-Thrower II super low resistance (0.6 ohms) 45,000 volt coil.

Adaptive dwell maintains peak energy throughout the entire RPM range, reducing misfires while improving engine performance.
Develops on average 4 times more available energy between 3000 and 5000 RPM, and 2 times more available plug voltage.
Peak current level is reached just prior to spark for maximum energy without the heat build-up, increasing coil and module life.
Adjusts spark timing at higher RPMs to compensate for the inherent electronic delay.
Senses startup and develops more energy for quicker, easier starting. Built in reverse polarity and over current protection shuts down the system, preventing component damage.
Legal in all 50 states and Canada (C.A.R.B. E.O. #D-57-2).
Guaranteed for 30 months.

[73Manta72gt]

I saw the specs they advertised, but wondered if anyone had real world experiences with both units to justify paying the higher cost of the Ignitor II.

[tekenaar]

Originally Posted by 73Manta72gt Originally Posted by Paul Originally Posted by 73Manta72gt Has anyone used both the ignitor I and ignitor II? Could you notice any difference in performance between them? Thanks Last time I checked, by calling Bug Stuff, the Ignitor II wasn't available for our cars. I think the new one is p/n 91847A, old one is p/n 1847V

Just added links to this thread's post quoted above and, just so everyone's clear, I thought I'd better expound a bit on the Pertronix published specs for all their "Ignitor®" triggers. All of their stated test results are for V-8 engines, exactly twice the number of cylinders as ours!

Fine, you'll say, so what?! . . . why is this important for a single coil ignition system, regardless of how triggered? Single coil ignition efficiency and spark output for any number of cylinders is all about that single coil secondary saturation (dwell) between cylinder firings, regardless of trigger accuracy.

As long as there is sufficient mixture in the cylinder, engine will fire whenever there is any trigger at all, but the coil's output spark voltage and energy is directly dependent on the amount of coil secondary charge reached between cylinder firings!

A coil is essentially a step-up transformer (voltage multiplier) with an ultra high - 1000:1+ - windings ratio. Points are simply an ON/OFF switch with a capacitor (condenser) as buffer to keep them from arcing. When the points are closed (ON), voltage is applied and current flows in the primary (LOW) windings and is stepped up in the coil secondary by its magnetic field.

The secondary continues this magnetic field voltage "charging" until the points open, turning OFF the coil primary windings "charging" circuit from ground. The secondary windings magnetic charge field collapses and the high voltage has nowhere to go but out the secondary coil wire, which fires the spark plug.

As already stated, any electronic trigger merely replaces the electro-mechanical function of the points/condensor with added benefits of "no wear", a constant dwell (coil charging time) and perhaps increased primary charge voltage. Those are the basics.

A quick word about my V-8 specs statement earlier. Each cylinder in a V-8 engine has exactly half the time between ignitions as a 4-cylinder engine does. It's easy to deduce from this that the single coil ignition system also has half the time to "charge" the secondary windings necessary for spark output.

All I wanted to point out is that most of the "advancements" of the Pertronix I, II and III were implemented for the specific shortcomings of the V-8 single coil ignition system and are much less critical in our CIH engines, even when modified to a degree. The primary benefit of the newer triggers on our CIH engines would be the somewhat increased trigger (primary winding) voltage.

For most of our engines that are seldom run up to "red-line", even those that are multi-carbed, somewhat cammed with bigger valves, you're simply spending more money for the P-II versus the original, without any real "noticeable" benefits, IMO. The original can be purchased at "Bug Stuff" for about $45, the P-II is priced at $122 . . . you make the call.

Anyway, if you're building an all-out "race" engine, you'll most likely opt for the CompuFire DIS (waste-fire) system . . .