Want to cut your alternator's load by HALF?

[Kid_Again]

follow VNV's advice, as usual....

...when he was working on the headlight relays for my '66 bb, all he talked about was the need for good grounds on these cars...makes sense and since we had to come home today for a wedding, i figured i would fart around with the '65 sb roadster (which lately, seemed to require more draw on the ammeter (not really an ammeter, it's a shunt device which measures the charging rate of the battery (thanks and a tip 'o da hat to MAD Electronics)) because i had the inclination to check the ground connections...

I should first state that the wiring harnesses on the '65 are new

second, it's now evident to me that the most crucial part of the wiring is the horn relay (thanks to VNV) because it is the power distribution point from the alternator to the entire car...so, i went to tighten up the screw that grounds the horn relay to the radiator support and it stripped right away :eek ...and that's the FIRST, best ground for the system!!!!

, so I spent the entire morning running new ground wires, sanding the mating surfaces clean, soldering all the crimp connectors AND adding dielectric grease...here's what I added:

secured the horn relay with a 1/4x20 bolt and sanded all surfaces before securing and added a second ground at the horn relay to the radiator support
r/r'd existing ground connector on the other side of the radiator support
added a fourth ground on the driver's side of the radiator support for the MSD and ran THAT ground to a new point on the front of the frame
added two grounds from the engine mounts to the frame (one on either side)
added TWO grounds from the dash cluster to the bird cage ( i may extend one of those grounds to the frame)

...took me all morning (with a lift) and what were the results of my efforts?
the ammeter now reads one-half of any reading previously (at any given RPM)
the car now starts RIGHT AWAY whereas i used to have to crank it to start
the lights all around are brighter


...way to go, VNV!!!

...now, I'm taking a bunch of 10ga black wire downa' shore to redo the '66


..a VERY easy fix with spare wire and exisitng connectors


.....i knew that the big problem with the midyear's electrical system was poor grounds but once i saw VNV at work, I knew the correct way to go about it..

 

[henny496]

wiring

Hello
Do you happen to have any links to the topics on wiring, when VNV did his? I remember him posting some of his work. but I am not sure how much he posted
I will be getting into this in a very short time and I have not done much wiring before at all
I did buy a Painless kit since I have a few new things to put on as well
take care
Tom

 

[Kid_Again]

It's really straightforward but for help, search this forum for references to MAD Electronics. I can't find their website right now. In fact, if you look at my past posts, you will see a thread that i started recommending that people talk to Mark (not VNV, just coincidence) at MAD and order stuff because he really knows what he's talking about and will spend a lot of time with you. Mark sells the relay kit and instructions to make this conversion.

For myself, I am always nervous around wiring because, when I first got my '66, I had a dash fire in the wiring harness. Makes a true believer out of you in a real hurry.

I can tell you that the wiring code is the same for the '65 and '66. Run two relays. Splice into the realys the tan wire for low beams, the light green wire for high beams (check the schematic to make sure I didn't reverse that). Take a new hot lead off of the horn relay bus bar for each relay, additionally ground each relay and now the voltage goes from the bus bar, directly to the relay and right to headlights without first having to go all the way back to the cluster and then back to the front again. As noted, redo all of your grounds

 

[BarryK]

I can't find their website right now./QUOTE]

here it is

http://www.madelectrical.com/electrical-tech.shtml

 

[vetteman64]

RE Want to cut....... load by half?

I have been comtemplating the Ron Francis add on ground harness, designed for fiberglass cars. Any thoughts on this?
Thanks, Joseph Rock

 

[henny496]

Hello
Thanks for the link Barry and thanks for the info Kid Again. I will call and see what I have to do/buy
Robert Pelland also told me of the relays, but like I said before, I have no experience with wiring. I am just really nervous about it
thanks
Tom

 

[BarryK]

Tom

wiring really isn't that bad if you just go slow, do one thing at a time section by section. Also, if you don't already have it get the color coded wiring diagram for your car from Don Olsen, they are best out wiring diagrams out there!
Even though your car isn't going to be stock and you will have to do a lot of custom wiring, a lot of the things will still get wired up the same (such as taillights, parking lights, interior lights, etc) so it will be helpful. Even the areas that won't be stock wiring on your car you can refer to his wiring diagramn to see how it should be done stock so you have a basic idea than you can work off that to change/modify it to your specific needs.

The info for Don's wiring diagramns is:


The diagrams are US $31.50 INCLUDING shipping by UPS to the 48 contiguous states - cash, check, money order, or PayPal

Each diagram is about 22x34" and includes ALL electrical options, fuses/circuit breakers (and their ratings), lamp numbers and locations.

Donald Olson
Olson Engineering
214 Prairie Circle
Bolingbrook, IL 60440-2720
630-947-3284
vetsvette2002@yahoo.com

 

[Kid_Again]

...nervous is good when working on the elctrical system...if you buy the stuff from MAD, just ask Mark to walk you through what needs to be done, he has infinite patience

 

[JohnZ]

I have been comtemplating the Ron Francis add on ground harness, designed for fiberglass cars. Any thoughts on this?
Thanks, Joseph Rock

I used his auxiliary ground kits when I built my Cobras and my tube-frame Grand Sport (all of which had generic Painless harnesses), but I wouldn't bother on a Corvette with production harnesses; just make sure all the ground paths and connections are clean and shiny, and all the ground straps and clips are in place as shown in the Assembly Manual. Most 40-year-old cars have dirty (or missing) ground connections, which create high resistance, voltage drop, and heat; cleaning them does wonders.

The attachment of the horn relay to the radiator support doesn't provide a ground path - it's just an attachment. The only ground circuit in the horn relay is for the coil that pulls in the relay to blow the horns, and that's the black wire that plugs into one of the two spade connectors on the bottom, which grounds through the horn button. The other spade connection on the bottom is for the green wire that feeds 12V to the horns when the relay pulls in.

 

[Kid_Again]

Thanks!

 

[Vetsvette2002]

How does the use of relays decrease the load or ouput requirements of the alternator?

It may decrease the current going through the switch, but the actual net effect will be to increase the load on the alternator - you are now powering the relay as well as the lights or heater or anything else for that matter.

The use of relays should also not increase the voltage going to the lights as there is no resistor between the battery/alternator output and the lights.

Don

 

[Mac]

How does the use of relays decrease the load or ouput requirements of the alternator?

The relays won't decrease the load but having solid ground throughout the system will. The better the path, the less energy loss & the more efficient the circuit... therefore the less on the alternator to power the system.

Positive power is distributed circuit by circuit but ground is often assumed through the metal framework. Having fibreglass bodied cars emphasizes the need for solid ground. Theoretically, the entire electrical system of a car could be grounded to a single 18 gauge wire connected from the battery to the frame. Practically, that wire would melt in short order because the energy demands exceed it's capability.

-Mac

 

[magicv8]

I would like to add that the ground for the birdcage is under the car at the body mount near the front of the LH rocker panel. IMO it takes a lot of crud and should be cleaned every 10 years or so, since it provides the ground for the entire cabin.

IMO the only really good thing relays do is take the load off the poor contact that the repop harnesses have on the red battery line connection from the engine bay (harness) to the back of the fuse box. It is especially important if you add a big stereo, etcetera.

I ended up running an 8 gauge (50amp) line from the starter solenoid through a circuit breaker to the battery line on the key switch, just to keep all my added electronics from nuking the harness connection - and my auxilliary 65w/65w headlamps already run off a relay. I haven't used the original headlamps at night for more than 10 years.

 

[Vetsvette2002]

The relays won't decrease the load but having solid ground throughout the system will. The better the path, the less energy loss & the more efficient the circuit... therefore the less on the alternator to power the system.

Positive power is distributed circuit by circuit but ground is often assumed through the metal framework. Having fibreglass bodied cars emphasizes the need for solid ground. Theoretically, the entire electrical system of a car could be grounded to a single 18 gauge wire connected from the battery to the frame. Practically, that wire would melt in short order because the energy demands exceed it's capability.

-Mac

Having a good ground will also not deceease the load on an alternator, but is will decrease the load thruogh that circuit's reduced ground size (resistance to current).

This is why our Vettes have 'Ground' circuits. The addition of more or separate grounds is treating the symtom and not the cause.

Don

 

[Kid_Again]

well, i may have confused the issue but yes, i meant that the "load decreased" when the only fix was to ensure much better grounding

..to a non-expert, once i did that, the output of the alternator, as measured by the "ammeter" decreased, with one meter displaying about one-half of the previous excursion..i don't know what to call it but it's inarguable that it's all good

 

[magicv8]

well, i may have confused the issue but yes, i meant that the "load decreased" when the only fix was to ensure much better grounding

..to a non-expert, once i did that, the output of the alternator, as measured by the "ammeter" decreased, with one meter displaying about one-half of the previous excursion..i don't know what to call it but it's inarguable that it's all good

It's a battery meter and it reads the voltage difference between the horn relay and the starter. Obviously the voltage difference between the two changed, probably when you fiddled with the connections on the relay or starter and cleaned them. IMO you changed the meter reading for the same electrical activity.

That's why I converted my battery meter to a voltmeter with a 0-16volt scale years ago. This spring, my voltmeter readings went up when I added the 8gauge power line to the cabin - solely because the meter no longer puts up with the voltage drop through the 12gauge line in the engine bay and the contacts to the fuse box. The car has same grounds, battery and alternator, but better connections to the meter in the cluster.

IMO JohnZ has it right, just clean the connections.

 

[Kid_Again]

well, you obviously know what you're talking about but with my experiences with my cars, i'll probably just practice superstitous behavior to ensure that i've done everything that i can to prevent another wire harness going up in smoke

cleaning the grounds was, for me, a great place to start

...i just cut in a master electrical cutoff switch (a manual Hella, i just COULD NOT bring myself to spend the bucks that VNV did on that sliding latch solenoid gizmo he uses (GEEZ is that expensive!!!!)) and therefore had to add new 2ga battery cable...this time i cleaned every contact point on the supply side of the battery and that, of course also slightly improved the position of the gauge needle (makes sense given what you have posted)


...but, of course, i added yet another ground wire since i was under the car ANYWAY

...you electronic experts can all it whatever you want, i call it peace of mind

the difference is astounding to me