Dwell angle, electronic ignition

Hah... no, I've owned exactly one Ford ('93 pickup) in my life, and don't think I ever regularly drove any others. However, it seems that I'm getting a new one because of some fleet management shift at work... so we'll see. (fingers crossed.) Last company car it was the water pump failing catastrophically... dunno what the typical Ford failures are :)

nate

Any brand of car you care to name has horror stories. Mine mostly involve VWs and Toyotas. My parents always bought Fords. I've been more diverse in my purchases (name a major lower cost brand, and either I've had it or someone close to me has - except nothing Korean). I've never had a truly unreliable Ford, although I did have a 78 Fairmont that must have been painted on a Saturday night by someone under the influence of something. The Ford trucks we have had for our farm have always been reliable. The ignition module in my Father 86 Ranger was about as bad as it got. My first wife had a 89 Taurus wagon that went to hell after we got divorced, but then the Toyota she drove before that was a smoking turd that was ready for the junk yard at 60k miles (worst car ever!). For the most part cars are much much better now than they were 30 years ago (or even 15). I sometimes get the bug to buy an old Mustang or Camaro or even something British (TR-6 for instance). But then I remember I lived through those once already and they weren't that good. I loved the 280Z I had in 1975, but then I remember the problems it had and I think I should just stick with newer stuff. I had a

Ed

Inductance has no bearing on final current. It heads for infinity or until you cut it loose. It's the RESISTANCE that limits the current. And it's usually small enough that you can smoke the coil in short order. That's why there's often a ballast resister in series wit the coil on a point's system.

The spark timing depends on when the points open. The energy in the coil depends on the current at the time that happens. You could probably measure what you've got in the current system vs. RPM.

A CD ignition works differently. It charges a cap and dumps it into the coil at spark time. I don't think dwell has much bearing on the system.

First task is to decide EXACTLY what's broke. If you're unwilling to poke instrumentation under the hood, you've got a significant handicap.

This is going to turn out like most projects. 99.9% trivial, and 0.1% expensive development failures. You're out of your element and must learn what the auto guys spent the last 100 years figuring out. Make sure the hood is well out of the way when you're under there. You don't want to rip a big gash in your head when you get shocked and come flying out of there. Don't ask me how I know.

I feel your pain. $350 will buy a few rounds of golf or dinners out. But what's the cost of being stranded on the mountain in a snow storm. Or in a bad part of town at Midnight. Or missing your plane.

Before I jumped, I'd look into after-market CD ignition conversions and see what's available. Might be easier to start with something with a tested/reliable high voltage/current side and interface that to your sensor on the low voltage/current side. Also, check the DEQ to see if it's legal for your vehicle.

AMuzi wrote in news:jnuadn$rjt$ snipped-for-privacy@dont-email.me:

THis is the exact one I have used for years to use any ign module on almost any vehicle. KB

jim beam wrote in news:jnu4rn$70u$ snipped-for-privacy@speranza.aioe.org:

since you know nothing about him of course your qualified to criticize him. You just can`t stand not being a blowhard can you?? KB

what do i need to know other than what he writes kev? did you bother to read it kev? or should i say, could you understand it kev? the evidence says "no".

as opposed to what kev? your and your, um, "contributions" to the knowledge pool?

that's not much of an endorsement...

inductance most /definitely/ has a bearing on current all the way up to saturation. and inductance /definitely/ had a bearing on time to saturation..

see above.

it's called a "kettering" system.

no, you're ignoring the core.

????

why does everyone keep bleating about cdi's? hardly anyone uses them except a few outdated aftermarket systems, and even those manufacturers quietly offer inductive systems as well because they know the reality,

why? why? why? cdi doesn't work as well. and why do so many people think electronic ignitions are all capacitive???

and just use an inductive retrofit module. chances are the o.p. can pick one up for a few bucks, and won't even have to change their coil. cdi requires coil change, so that's even more expense on top of the hundreds spent on aftermarket that won't work as well because it doesn't deliver as much energy.

why? why? why? just replace the module and retain the other stock [inductive] components.

Okay, I got "The Doctor's Step By Step Guide to Optimizing your Ignition" which was $3 at thriftbooks.com.

It's not good but not bad. It does flog some of Jacobs' products, but less than you'd expect for a book like this. It has some interesting and useful stuff like his method for estimating horsepower on the road which is really kind of ingenious.

It has a lot of advice in it that is good advice but is not backed up with proper explanations of any sort. His basic electricity introduction is misleading and doesn't include some of the stuff that is needed for some of his later discussions. It also has some advice that seems a little suspicious to me.

It has basically zero information about what is really going on inside the box.

On the other hand, some of the empirical "I tried this and it worked and I tried this and it didn't" could be very useful.

And, the discussion of reading sparkplugs (and how reading sparkplugs for performance tuning is not really as useful as it used to be) is very very good and makes a lot of points that people seem to ignore today.

So, I'd give it a 2/5. I'd give the TAB book by Brant a 2/5 also, but the information in the Brant book is a lot more detailed about what goes on inside the box. Either one is well worth $3 on thriftbooks.

--scott

snipped-for-privacy@panix.com (Scott Dorsey) wrote in news:jqt2r7$4g2$ snipped-for-privacy@panix2.panix.com:

Good, and my point was any box you get your hands on you can use as per Jocobs instructions. much cheeper than reinventing the wheel, unless you want a elect project. KB