Hotter spark for next to nothing?

[4wdchico]

Was thinking about the difficulties involved with improving our all in one distributor system. Some folk have used voltage boosters to apply around 18 volts to their ign. systems, but I'm leery of burning out the old electronics. Got to thinking that there has to be some voltage drop on the hot lead to the dist. due to age/use. Got out the DVOM and running bat voltage is 14.83v on my '85 t4wd. Checked the running VD at the harness side of the green plug that connects to the dist. pigtail & got a VD of only 0.32v, that leaves me with over 14.5v at that point, not bad. Decided to check the other side of that connector for grins & got a VD of 2.04v. That is significant enough to warrant some attention.

So the plan, at this point, is to see if I can clean up and tighten that connector and eliminate that large VD in it. If I can't get the VD down to a reasonable level, I'll install a relay (circuit breaker protected) and some heavy wire right to the dist. pos. input and apply full battery voltage to the ignition system. I should be putting in around 15% greater voltage at that point, and it should translate to a little over 10% greater spark. Pretty good for a quick and easy repair/upgrade (upgrade if the relay is required).

[ARCHINSTL]

Wow! Have to check that when it stops raining.
If your mod works, do a writeup (and a pix/diagram for us electrically-challenged folks) and we can move this to the Repair Guides section.
Tom M.

[Petros]

A 2 volt drop across a connector? Sounds like it needs some attention. You can carefully pinch the female end of the metal connector inside the plug so it grips better, I have had to do that a number of times in old cars, including my Tercel. Clean it with electrical contact cleaner, fine wire brush, and use something like LPS1 to improve contact. That should improve the connection considerably.

Let us know what you find.

[4wdchico]

I opened up the connector, removed the female portions of the blade connectors and tightened them up. Then a little filing of male blade connectors with a jeweler's file and a quick shot of contact cleaner. Reconnected everything and the VD was reduced to .28v, pretty respectable. I tested a buddy's '85 t4wd yesterday for VD at the same point and came up with a VD of.30v, guess that that is the nominal resistance of the ignition circuit to that point.

[takza]

With "new" old cars I usually go through all the connectors under the hood to check for corrosion. You can tighten up the female side of each connx by using a jewelers screwdriver ...twisting it on the split side (female side)to make the connx better (don't crack the plastic)...plus I use some WD40 or di-electric grease...also reconnect it a few times.

[4wdchico]

With "new" old cars I usually go through all the connectors under the hood to check for corrosion. You can tighten up the female side of each connx by using a jewelers screwdriver ...twisting it on the split side (female side)to make the connx better (don't crack the plastic)...plus I use some WD40 or di-electric grease...also reconnect it a few times.

That method can work pretty well. I like to pull the female side of the connector out of the plastic by inserting a pin in down in on the unsplit side of the connector to release the tang that hold the brass part into the plastic. Once the female connector is out you can adjust it's holding power (bend that sucker)very accurately

You have a great policy there. I don't do a physical connector check anymore, I just check for voltage drop and clean & retighten as needed.

[takza]

That voltage drop video was good. I googled "voltage drop test" and got a lot of hits...good articles.

Found that video in Youtube...

http://www.youtube.com/watch?v=v0THDAS1nws

Voltage testing is a bit more useful than just checking all connxs.

[splatterdog]

A relay feeding the component direct batt voltage can certainly help. Relays draw about 1/4 amp putting very little demand on a typical 15a circuit. 20 year old switches can live with that reduction.

Direct power from the batt will increase output over a circuit with numerous connections(crimps,terms,switches,fusebox). I have upgraded a few headlight systems and the results have been good. On the quad headlights I add a diode so the lows are on with the highs. My old turd suburban puts many newer aero lights to shame without fancy bulbs. I've got the GM only mini sealed beams for which there is only "standard halogen" bulbs. On 2 light systems I have been tempted to light up both filaments at once on high beam. I'm sure bulb lifespan would be decreased, probably greatly. My biggest concern would be plastic housings melting on the newer plastic cars.

But, with higher voltage comes shorter component life. Higher performance usually comes with a price. Better spark,lights or whatever would be worth it to those concerned...