John at Aircooled had me swap out the points and condenser on the SVDA and all is well. Dunno what is faulty, the points look and seemingly work as they should. Could have been the condenser.
So I ran some errands this morning with the 009 in the Wonderbus, then switched over to the repaired SVDA - this confirms my impression of yesterday: the SVDA is peppier, crisper, and makes the bus just more darn fun to drive. 009 feels vague, squishy, and sluggish by comparison. I recommend the SVDA, and can affirm that John's reputation for excellent customer service is accurate.
...................I have one of John's SVDA's installed on my '77 bug as well. For those who are running with the L-Jetronic FI, it works very well in place of the original dual vacuum unit that came with the FI engines.
I hope you realize you've just put your name on the Kiddie Trade shit-list :-)
I've been saying the same thing for more than thirty years, ten of them right here on the Internet. Not kewl of course, having a bug, bus, ghia or thing that just keeps going and going and going and... But it sure is fun to have a vehicle you can DEPEND upon; something that will carry you anywhere you want to go, when you want to go there... and bring you safely home again.
Terrible thing, being un-kewl :-)
-Bob Hoover
PS -- vacuum advance carb and a CDI module will boost your mileage 10%, minimum. But of course, that can't be right...
Well gosh. I feel terrible, just terrible, about that.
Yup. This is a daily driver. I didn't expect to have to do as much work on it as this, but now that I have it, I feel a sense of responsibility to set wrongs right and leave it better than it was when I got it. Plus it's fun to learn new skills.
I drive the kids to school along Highway 78 (San Diego's North County)and through Vista in the morning in commuter traffic. If Dad's going to be silly enough to drive an old bus, at least Dad can do his darndest to make it a reliable old bus. That's cool enough for me.
Better mileage is good. Lowered emissions is also good, as a side effect, if possible. What I wonder about is reliability of CDI systems
-- like Compufire/Pertronix -- vs. points, and ease of getting back on the road if system breaks down when compared to popping in that spare set of points I have in the bus. Can't tell from Compufire's website or their online installation manuals if their unit has a bypass/fallback mode to allow use of mechanical points or not. Worst case just pack my
Compufire or Pertronix are just pojnts replacements, not CDI. A CDI will have more "intelligence" in it, has a control box and offers stronger spark. Some allow the owner to adjust certain values like rpm limiters and such. Some produce more than one spark per combustion stroke at low rpms. Some just consistently give one fat spark.
Compufire and Pertronix and the multitude copies out there ofer reduced maintenance and wear, and eliminate "bounce" at very high rpms. "Set it and forget it". They also allow you to get rid of the condenser (one less part to fail).
Install either of them, and keep a clean set of points and a new condenser in the glove compartment in case of emergencies, if the Compufire/Pertronix fails on the road. (They rarely do, the #1 reason they fail is crossed polarity when installing them.. ZZAP.)
Replacing the compu or pert is just as easy as replacing normal points out there on the side of the road. If you didn't carry a spare set of points, you are just as screwed no matter what you had in there :D
A true CDI unit will work with both normal points, as well as magnetic pickups like Pert and Compu. And it can be disabled to allow you to return to "conventional" ignition with points. (By what, taking one wire off one terminal and placing in in another?)
First off, Compu-Fire and Pertronix are NOT CDI modules; they're transisterized switches that replace the points. They eliminate the maintenance associated with points but they don't do anything to enhance the energy delivered to the spark plugs. As your rpm increases, your spark voltage is going to fall, exactly as it does with the stock Kettering ignition system and for exactly the same reason -- the RL losses in your coil and the decreasing amount of saturation time with higher rpm.
Capacitance Discharge systems use a different principle. Your plugs will see the SAME amount of energy from idle all the way up to about 6000 rpm (for a four-banger), assuming you buy the El Cheap system from Universal (which John sells on aircooled.net) (Gotta big V8 turning eight grand? Then you'll probably be happier with a bigger box; MSD or whatever.)
As for durability, from the mid-70's thru 1992 I installed at least 200 CDI modules, most of the same design as the Universal. (It was also sold by Radio Shack [Archer?], Heathkit and several other outlets... same circuit.) In all that time I had exactly TWO failures and both were crib-deaths -- dead right out of the box -- and were replaced without any hassle.
As for what to do SHOULD one fail, if it was a Heathkit you simply pressed the Big Red Button. That cut the CDI out of the circuit and you were back with your stock ignition system. With most of the CDI's from Universal you accomplished the same goal by reversing the wring plug... arrow UP, CDI; arrow DOWN, stock.... and drove on home.
Which doesn't mean I don't carry a spare distributor, extra points and so forth. (Hell, I even carry a spar clutch disk.) But so far, I haven't had to use it. I had a plug foul on me last time I was down in Baja but I think it was due to a bad tank of gas I got at Mulage (the old Pemex station in town, not the new one south of the river).
Aw, I knew that. Just last week I straightened out the difference in my head. But my head is 54 years old and it filed this information in the "think harder, numbskull" department. Which I didn't do.
This makes sense.
Only for 6-volt systems, near as I can tell. Anyone gotta recommendation for 12-volt El Cheapo system? Or a vendor for Universal's 12-v version?
[snip]
Good track record.
Simplicity itself.
What about emissions? It's something I am sensitive to, and while I know that if I was not driving this bus, someone would be, so the net amount of emissions added to the air here in SoCal would probably be unchanged, I would like to do what I can to lower this engine's output of pollution. Have any studies been done of VW (or VW-type) engines w/ CDI vs. coil-type -- Kettering -- ignition w/r/t emissions?
Stock carburator: use the SVDA. Dual carbs, or something other than stock: Use 009.
Can't go wrong. Those who want to stretch the SVDA a little further will need to know what they are doing, but it can be used with non-stock carburators too, if you manage to provide the dizzy with correct vacuum signal. That's the key.
I have dual carbs and used the 009 until I put in the SVDA -- won't be going back.
I had John provide a modified throttle body with the vacuum signal port on it for my right-hand Solex/Kadron carb. The trick, as I understand it, is making sure that the vacuum signal matches the distributor's advance mechanism and your engine requirements.
What options do I have available if my carb is a 30 pict-1?
aircooled.net says the SVDA cannot be used with it, if I'm reading their little tech section correctly.
This was gonna be one of my to-do items this spring, as a sort of apology to my beetle for the abuse I put it through, but it seems like I have limited choices unless I include a carb swap.
Which I'm inclined to avoid because I like keeping things stock, but discussion on ramva the past year has really turned me off on the 009.
Because I listen a lot more then I talk, and when guys like Bob Hoover take a breath to speak, I shut up immediately to hear what he has to say; it will almost always be useful, or funny, or BOTH. ;-)
except the new IDFs have the correct vacuum port on them for proper vacuum advance operation. There's no excuse to use an 009 other then "it looks cleaner" anymore. If you really want nice, get a mallory, but those aren't cheap.
These usually have the proper port Thomas (for an SVDA). If the SVDA doesn't drop the oil temps 15-20 degrees, 3-4mpg improvement, and better throttle response, 100% refund.
Any time you enhance the burning of the fuel, you lower emissions. (Now THAT should get some, "NOT SO!" responses!) (Also why I said "enhance the burning") Basically, make it run better and it runs more efficiently or vice versa. John used to sell one brand of CDI but there were problems with it. He may well have another brand now, or have figured out a work-around for the problems! He should be jumping in here with a statement soon... You might e-mail him and ask directly. BTW, re points eliminators: I used Pertronix and loved it. Never any maintenance on ignition after install. Without it, I was adjusting dwell and timing all the time. I had two units fail. One had a problem in design, the other, a few years later, worked very well but late one night I hooked the coil wires up backwards and fried it instantly! Lotsa smoke real quick! Back to points, I had a nice smoothe points cam, but still wore them down pretty quickly. I started using anti-seize compound on the point cam and never replaced points or adjusted dwell or timing after that (many many many miles!) I strongly recommend it. I also carried spare points and condenser and spare points screws - you always drop one when you're doing an emergency replacement alongside the road! Now, of course, carrying spare points would be pointless! -BH
John no longer has an econo CDI w/ some kind of fallback/bypass mode for in case the electronics fail. I'm currently seeking recommendations for a reliable budget 12v CDI w/ bypass.
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