ignition system for a VW

[raygreenwood]

John...very well put reply. Skeptic...you two are talking about totally separate things. Coil packs have nothing to do with something such as compufire or pertronix basic igniter. Those are simply switches....not coils. They generate no power. But yes... capacitive inductance type coil packs can provide stellar performance, and sometimes have notoriously short lives. Capacitors can burn out. High quality properly sized and cooled systems are very expensive. American cars are not known for the expense of their parts...or the soundness of their warranties. usually it is poor cooling and high resistance due to cheap insulating materials or bad weather seals that do these parts in. They also provide a service to a moderate to high performance system that is very hard to duplicate with points, wires and standard coils. I does depend upon how you are driving what you have...as to wether you notice a need for something other than stock. Ray

[redcorradoguy]

I have a pointsless system in the bug (1600 DP) (don't actually know who made it) and I must say, I do enjoy the fact that there is one less thing to worry about adjusting every so often, even if I didn't get anything else out of the system. (and I think I did)

I'll probably look into the Pertronix system since it has been recommended for the bus, as it sees a lot of highway miles at decent speeds (65-70), and I have been able to feel what feels like losing spark sometimes. Plus, I won't have to adjust its points again either!

David

[Guest]

I can honestly say, that I love my current setup in my '71 Westy. I have a single 34 PICT, with a SVDA distributor and a Compufire ignition module. The PO thought the engine was bad, despite it being only 4 years old and having good compression. He replaced everything on it in an attempt to fix it. I replaced the distributor pinion spring, intake manifold rubbers and gaskets and the points. Now the engine runs like new. As a side note, you can?t beat the PICT 34 and SVDA combo for bus with a 1600 DP.

[DingoDog]

Appropo to the topic, just finished building a homemade CD (Capacitor Discharge) unit for my Bus.It puts out quite a strong spark (as I..er , found out) and has a switch to flip over to good old points if neccessary. So far so good. Cant tell if it makes any difference...but it does look cool!

[redcorradoguy]

Appropo to the topic, just finished building a homemade CD (Capacitor Discharge) unit for my Bus.It puts out quite a strong spark (as I..er , found out) and has a switch to flip over to good old points if neccessary. So far so good. Cant tell if it makes any difference...but it does look cool!

Any pics?

[DingoDog]

Ive already mounted it in the bed-closet, enclosed within a computer power-supply box with built-in cooling fan, so the pic would be hard to get.
I got the schematic off the web from a guy named Noble who has been helpful with hints. He says he used it on his air-cooled Porsche 356 for 50 000 miles without a hiccup. I modified it to take 12V instead of 6V, and am hoping for the same longevity! I have since found some more updated schematics using chips, and knowing my brain, I will be building some of them too. let you know how it pans out.

[amskeptic]

Skeptic...you two are talking about totally separate things. Ray

I have nothing to say about coil packs in this conversation about breaker points versus Pertronix. It was merely one of three examples of stranded motorists I picked up alongside the road. I have no discussion about roll pins in BMW distributors either.
That was my point. And you and I are on the same page when it comes to the propensity of electronic parts to fail and fail totally when they do so.
I own a late model BMW 5 Series that is as electronic as you can get. And though I am sure that its electronic ignition system is the only way to fly with that M60TU engine, I would much rather take my VW Bus on a cross-continent jaunt from Alaska to Baja California because I know I will get there and back. This is an appropriate perspective to share with any air-cooled VW owner who wants to drive, drive hard, and drive far. These cars have a world-wide reputation for toughness in every climate, why botch up good original engineering for instantaneous "performance" and sacrifice legendary reliability? A Bus isn't half so much about how fast it will get you there, but rather that it *will* get you there with your entire family, three dogs, the Christmas tree, all your luggage, two bicycles. and Grandma's hutch. . . and it will be a fun trip, even with the stop to fish out the breaker points from the glove box and gap them in with a E-Z Wider cover flap. . . Colin

[DingoDog]

First outing with the CD Ignition unit (Sparky I) was an eye-opener. 1st and 2nd gear have all kinds of power that i never knew existed. I was delighted. Didnt get to test it on the freeway, since after a stop at the store to quench my thirst, the CD wouldnt fire-up, so I flipped the switch back to 'Points' and drove home merrily. So , yes, Kettering will get you to Tierra del Fuego and back, but theres some definate 'oomf' to be had out there with CD. Sparky II is already under construction...some better components and soldering and it should be back in business. Meanwhile the loyal and reliable 'points' will get me to Radio Shrek and back.

[raygreenwood]

Skeptic...yep we are basically on the same page. I'm the first to admit that I carry a points and condensor in the glove box. I do this simply because of parts availability on the road...if and when the pertronix ever craps. So far though...I have never had a problem with it. Although I have had burned points and bad condensors in the past...I carried spares then too. But...I have found noticably better operation with the Pertronix than points. Ray

[GoKayaking]

I have used both stock points and Pertronix ignitors in several busses. I have never been able to tell much difference in busses with carbs, but I really like the Pertonix in fuel injected busses. Since the ignition system provides both the spark and the FI signal it is a double whammy if the points skip or stick. This is especially true over 4,000 RPM under hard acceleration. This isn't as noticable in a carbed bus, but it certainly is in the FI busses. I laugh my a$$ off everytime I see some seasoned VW mechanic yank off stock L-Jet and replace it with an inferior carb setup while cussing like a sailor. Twice I have purchased these systems for practically nothing and run them for 1000s of miles. My current 2.0 liter FI bus has a Pertronix and a $35 FI system that I dug out of the trash can of a mechanic who claimed to have 30 years experience. He hated FI and he refused to consider a Pertronix instead of points. FI and Pertronix are a great combination and I have about 25,000 trouble free miles on my $35 FI and $60 Pertronix.

[amskeptic]

I sold my '78 BMW 530i in 1993 which was equipped with both L-Jetronic Fuel Injection and good 'ol breaker points and condensor. It had a 6,400 rpm rev-limit, ( point gap was .016 just like the VW, 8.5:1 compression ratio) and was firing the coil 320 times per second at red-line, That is equivalent to a 9,600 rpm red-line in a VW. Both the L-Jetronic and the Bosch points/condensor/coil set up are alive and well in Atlanta at 320,000 miles. I think L-Jetronic is an excellent system, easy too, and I think breaker points and condensor are more than adequate for high rpm operation, with the following caveat, point gap should be no more than .016" with a dwell of 44* for high rpm driving. If you are losing sparks at high compression, lean mixtures, and high rpms, then you need to ensure all of the system resistances are correct, 10K ohms through the rotor, 5-10K ohms through the phenolic connectors at the plugs.
I dunno, I am just leery of the after-market hype. . . . directed at us stock air-cooled owners. Like everyone else, I admire the hell out of the high-performance searchers at LN, RAT, etc, and their solutions I would not quibble about. But way down here at 5,400 rpm at 7.3:1, stock'll do.
Colin

[GoKayaking]

I think L-Jetronic is an excellent system, easy too, and I think breaker points and condensor are more than adequate for high rpm operation, with the following caveat, point gap should be no more than .016" with a dwell of 44* for high rpm driving. Colin

I certainly second that. Actually I would have a lot more of my long golden braided locks remaining if you would have told me that 5 years ago rather than letting me figure it out for myself. I tried many times to set points at .020" to allow for wear, but I finally decided the L-Jet just didn't like anything more than .016" and it seemed too difficult to maintain that precise gap. Call me lazy, but I like going 25,000+ miles without changing points or setting timing and that is nearly impossible with such a narrow point gap. Even with Bosch parts and impossible with cheaper parts. My Pertronix gives me consistent long term service and now I have more time to maintain what little hair I have left.

[raygreenwood]

Colin, one point missed about your BMW. It is watercooled. Even at decent compression, the cooler head temps create a better environment for not misfiring. The problem with points...and it is fact...is that the dwell time needed to create each spark is shortened, as RPM climbs...hence the reason why many newer systems have been and are going to CDI. The weak point in the whole points system is two fold. (1) the overall voltage that your coil is able to generate before the points open, is greatly reduced as swell time gets shorter at higher rpm. ie: if its an 18-22,000 volt coil...as most stock VW are, you are getting considerably less than that when you are near the design limit. Even more is lost in a high resistance point system. All of them are higher than points replacement modules. Most BMW coils put out closer to 35,000. Even then, the Bosch systems used in the BMWs, Mercedes, volvos and SAABs in that era were notorious for not being able to even approach their redlines without fall-off. The higher the compression...the more energy is needed to reach ionization point at the gap. So the hotter the engine ..the worse it was.
(2) The condensor. The harder it runs...the hotter it gets...the hotter it gets...the less efficient the transfer. The condensor is the main reason points burn and pit. Burned points are an uneven gap and inefficient spark. Resistance is infinitly variable at that point
The point about insulation and condition of parts is 100% correct...and well taken. Most people only replace their wires and boots when the engine lights up by itself at night. Resistance of rotors and wires is still an issue even with points modules. Common variance from stock on all ignition parts from the box....is about 7-10 (got that from an SAE paper some years ago. I will look for it). The points have the most manufacturing variance of all. A nice example was the commonly misaligned poiints from Bosch that came here when that manyfacturing process went to Brazil in the late 70'2-early 80"s. Also notorious, were the fusion welded stationary stud of the early to mid 80's Bosch points. 90% or them were defective out of the box. The only good brand of points I found in those days...were blue streaks at $9 a set from standard ignition components. Thats when I changed to a module. The uniformity has been fabulous.
In short, the question is not really if the stock system is "adequate " for ignition. The question is wether a module will produce noticable rersults with less maintenance on a properly tuned motor. The answer is yes. The voltage required by the switch itself, and the more uniform switching WILL produce a more uniform spark. Its math...its physics...it works very well. Is it more dependable? I'm in agreement with you...that is debateable. Personnally, I have never had a problem with any electronic ignition...other than the system on the one and only chevrolet I have owned. Ray

[vok914]

It depends on the configuration motor you have or want to build. Just that type of ignition in a stock motor don´t do it better than a 009 bosch. And in the 009 you can install a electronic system.