voltage regulator for electronic ignition

Posted By: 69fishes

voltage regulator for electronic ignition - 04/22/10 07:44 PM

I have a 1969 Barracuda 340 engine with an electronic ignition and stock voltage regulator. The car is next to impossible to start when cold. The battery has 12.5 volts. I charge the battery to a higher voltage and engine start easier. I think I need to go to a 1970 and later electronic voltage regulator to increase my voltage. Am I on the right track? What wiring has to be changed? The later electronic voltage takes a plug and my harness has spades for the stock regulator.

Posted By: MoparforLife

Re: voltage regulator for electronic ignition - 04/22/10 07:52 PM

You would have to upgrade to the later dual feed field higher output alternator to do this. Some refer to this as double field alternator but in reality the others also have 2 fields but one is grounded internally. Really the alternator you have now should keep that battery charged if you aren't running with a bunch of electrical draw assesories.

Posted By: Dougsmopars

Re: voltage regulator for electronic ignition - 04/22/10 08:19 PM

Use the Mopar blue performence regulator. Plugs right in. Constant out put. Works beautiful. Been useing them for years with no problem.

Posted By: therocks

Re: voltage regulator for electronic ignition - 04/22/10 08:31 PM

Just get a new replacement electronic type that looks like the points one.My kid has one in his 413 and with MSD and big stereo it cranks right up all the time.I did the dual field change on my 65 and his charges just as good even with the 62 alt still on in.If it wants to crank hard a different alt wont fix your problem unless it barely charges.Ive used the new replacemebt type reg on 4 cars and they all started and charged like a new car.The blue reg is a race unit and will not just bolt in on a older car.Rocky

Posted By: Dougsmopars

Re: voltage regulator for electronic ignition - 04/22/10 08:52 PM

Yes it will my friend. Uses the same 2 wires. I use them on every big block with electronic ignition.

Attached picture 5941142-MyGTX062.JPG

Posted By: 05dakota

Re: voltage regulator for electronic ignition - 04/22/10 09:49 PM

not whats causing hard starting

Posted By: RapidRobert

Re: voltage regulator for electronic ignition - 04/22/10 09:56 PM

Quote:

not whats causing hard starting

X2. Is it cranking way slower when cold & if so are the cables clean and do you have a known good newer batt to borrow to see if that speeds it up. To test a battery you would slow charge it overnight & have a parts house test it but most dont have the right load tester so the test is invalid and it's just as easy to sub one in real quick. If it is cranking good is the choke right but from your Q I'm assuming that it is a cranking speed issue.

Posted By: stubbs300

Re: voltage regulator for electronic ignition - 04/22/10 11:00 PM

Read this, http://www.imperialclub.com/Repair/Electrical/charging.htm

Posted By: MoparforLife

Re: voltage regulator for electronic ignition - 04/22/10 11:09 PM

Exactly what we have said - in order to up grade to the regulator above you also need the dual outlet field alternator use after 69

Posted By: Dougsmopars

Re: voltage regulator for electronic ignition - 04/22/10 11:35 PM

To use the 70 style regulator you need to change the alt. To use the mopar performence regulator you don't

Posted By: MoparforLife

Re: voltage regulator for electronic ignition - 04/22/10 11:39 PM

Quote:

To use the 70 style regulator you need to change the alt. To use the mopar performence regulator you don't

If you say so.

Posted By: Dougsmopars

Re: voltage regulator for electronic ignition - 04/22/10 11:41 PM

There it is on my car. Look at it. Same 2 wire as early regulator. Try reading the race forums. Try doing some reasch. Call your local speed shop.

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Posted By: Dougsmopars

Re: voltage regulator for electronic ignition - 04/22/10 11:45 PM

Mopar Performance Voltage Regulators Voltage Regulator - 13.5 V Constant Output - Race Only - Chrysler - Dodge - Plymouth. Fits many Dodges, Chryslers, and more from 1959 to 1969.
Brand: Mopar Performance, Mfr Part#: 3690732
Lowest Price $25.88

Product Details

To ensure your ignition and electrical system can provide maximum performance install a constant output voltage regulator. Voltage is held at a constant 13.5 V as opposed to the production regulators fluctuation from 11.5 to 13.5 V.

Attached picture 5941385-3690732.jpg

Posted By: MoparforLife

Re: voltage regulator for electronic ignition - 04/22/10 11:51 PM

Fine but as we have all stated that regulator will not work with the newer higher out put alternators unless you ground one of the fields. And the regulator we were referring to will not work on the older style alternators. The his oem system should work fine if his battery is in good condition and the connections are clean and all grounds are good. Shouldn't need a band aide constant out put regulator on it.

Posted By: Dougsmopars

Re: voltage regulator for electronic ignition - 04/22/10 11:58 PM

He has a 69. That is the older style alt. It's not a band aid it's the best regulator to use with electronic ignition in a mopar. Do your home work.

Posted By: MoparforLife

Re: voltage regulator for electronic ignition - 04/23/10 12:32 AM

Quote:

He has a 69. That is the older style alt. It's not a band aid it's the best regulator to use with electronic ignition in a mopar. Do your home work.

Homework - Hell I was working on these things when you were more than likely in 3 corner pants or before. Constant regulators are not meant and never were recommended to be used on constant running applications, but on race applications where short term charge is needed to keep a battery fully charged A good charging system is all that is (should be) needed and that constant 'flow' regulator is not the answer. If you feel that it is then go for it.

Posted By: Dougsmopars

Re: voltage regulator for electronic ignition - 04/23/10 12:44 AM

I'm 53 so unless your 80 i don't think you been doing anything since i was a kid. I been useing those regulators since they came out. Never a problem. There are a few hundred Mopars around here all useing them. We must all be stupid.

Posted By: MoparforLife

Re: voltage regulator for electronic ignition - 04/23/10 12:53 AM

Quote:

I'm 53 so unless your 80 i don't think you been doing anything since i was a kid. I been useing those regulators since they came out. Never a problem. There are a few hundred Mopars around here all useing them. We must all be stupid.

Still got 10 years on you and started working on them for a living in 67. Was twisting wrenchs on cars and trucks since I stared driving and at age 10 was hauling to elevators with grain trucks and had my license just by my 13th birthday.
Glad to hear that you haven't cooked a battery (yet). Never were meant for constant street use but if you want to use them go for it. Few hundred I would doubt but if you say so.

Posted By: 69fishes

Re: voltage regulator for electronic ignition - 04/23/10 02:55 AM

Thanks for the input. I put a reconditioned proper date coded alternator last fall. Since I posted the question I re-installed a rebuilt alternator that I had previously used. I am charging the battery and will try starting the engine tomorrow to see if I have more success.

Where can I purchase the 3690732 regulator you referenced?

Posted By: RapidRobert

Re: voltage regulator for electronic ignition - 04/23/10 02:59 AM

Quote:

Where can I purchase the 3690732 regulator you referenced?

Call your MP dealer and or see if mancini or Summit carry it.

Posted By: 451Mopar

Re: voltage regulator for electronic ignition - 04/23/10 03:20 AM

Year One sells a OEM looking voltage regulator that has electronic internals for $36.
That may help, but your starting problem is probably bad battery cables or grounds. You could also try the diode trick across the ballast resistor.

Posted By: RapidRobert

Re: voltage regulator for electronic ignition - 04/23/10 03:32 AM

Someone here in the parts for sale section sells on oe appearing one w a black case and electronic internals for $25 to your door and I understand the some regs can handle more current??and not needed in your app here but I understand you can replace the grounded brush on one of the 69 earlier alts w a insulated brush holder from a 70 up alt to make an isolated field (later type) alt if you ever wanted to use an an earlier alt w a later type 70 up flat VR.

Posted By: dave571

Re: voltage regulator for electronic ignition - 04/23/10 03:34 AM

Quote:

Year One sells a OEM looking voltage regulator that has electronic internals for $36.
That may help, but your starting problem is probably bad battery cables or grounds. You could also try the diode trick across the ballast resistor.

I think Napa sells one too. It's not that complicated.

The "dual field" thing is a misunderstood myth.

I used to sell the FBO conversion regulators, but you can't get them anymore.

13.5 constant seems like a wierd plan to me, when a stocker is quite constant, and usually above 14.
In the same breath, lot's of guys have runt he constant regulators without issue.

Posted By: MoparforLife

Re: voltage regulator for electronic ignition - 04/23/10 03:37 AM

As I stated on an earier post teh dual field thing is misunderstood and they both have dual fields burt the early alternator has one grounded internally. To use a later (70) up alternator with the older style regulator is to ground one of the field terminals either to the case or with a short jumper to any good ground.

Posted By: dave571

Re: voltage regulator for electronic ignition - 04/23/10 03:46 AM

If we are being picky, Really, both only have one field.

An electro magnetic field is like anything else elctrical. It needs power, and ground.

On the old ones, the power is regulated, and the ground is constant through the case of the alternator.

On the newer ones, the power is key on battery voltage, and the ground is regulated through the second wire.

Yes, grounding the second terminal completes the circuit when running a newer alt, with an older style reg.

Posted By: 451Mopar

Re: voltage regulator for electronic ignition - 04/23/10 04:03 AM

Quote:

If we are being picky, Really, both only have one field.

An electro magnetic field is like anything else elctrical. It needs power, and ground.

On the old ones, the power is regulated, and the ground is constant through the case of the alternator.

On the newer ones, the power is key on battery voltage, and the ground is regulated through the second wire.

Yes, grounding the second terminal completes the circuit when running a newer alt, with an older style reg.

The whole dual field thing just means two wires/connections the the alternator field winding. The older alternators only had one wire/connection because the other was grounded to the alternator case.

Posted By: therocks

Re: voltage regulator for electronic ignition - 04/23/10 09:18 AM

With the new elec reg that looks oe you dont need to cut or change wires.My kids has been in for at least 10 years and charges like a new car.The race reg was meant for that application.Not street.If they wanted a constant charge they could have built it that way and probally would be cheaper.Battery only wants so much charge.Thats why the reg shuts down when its charged fully.Unless you only drive a few miles sooner or later it will shorten the battery.I run 1 gauge cables.Ive seen a lot of older cars that have corossion in the cables that you cant see that cause hard cranking.Rocky

Posted By: MoparforLife

Re: voltage regulator for electronic ignition - 04/23/10 10:41 AM

Quote:

With the new elec reg that looks oe you dont need to cut or change wires.My kids has been in for at least 10 years and charges like a new car.The race reg was meant for that application.Not street.If they wanted a constant charge they could have built it that way and probally would be cheaper.Battery only wants so much charge.Thats why the reg shuts down when its charged fully.Unless you only drive a few miles sooner or later it will shorten the battery.I run 1 gauge cables.Ive seen a lot of older cars that have corossion in the cables that you cant see that cause hard cranking.Rocky

Posted By: Supercuda

Re: voltage regulator for electronic ignition - 04/24/10 01:42 AM

It's a dual field connection, which got shortened to dual field in usage.

Difference between the old and new style regulator boils down to this. The old style regulator switched the voltage to the alternator, turning the charging on and off.

The new style varies the ground and can control the output in a smoother manner.

Temperature compensation was built into the OEM regulators, the MP constant output one does not compensate for temperature, which is the ONLY difference. Might it shorten battery life? Maybe, I ran one for years and my battery lasted for 8 years with one. YMMV.

Posted By: dave571

Re: voltage regulator for electronic ignition - 04/24/10 02:57 AM

Quote:

...Battery only wants so much charge.Thats why the reg shuts down when its charged fully......

Thsi part is bunk.

Every chsrging system maintains a steady voltage while the car is running. 13.5 to 14.5 on most. The battery is fully charged at 12.6 to 12.8. I've seen lots of older cars that charge closer to 14.9, without issue. Obviously, a steady charge isn't the problem.

I don't know why the constant voltage race unit isn't recomended for the street(I wouldn't run one on the street myself, simply because I don't see the point), but I would theorize it is related to the temperature compensation that has been mentioned, and perhaps even a reliability stand point. Specified as a race only piece, it may not have as long of a duty cycle as a oem unit.

Posted By: MoparforLife

Re: voltage regulator for electronic ignition - 04/24/10 11:46 AM

So now we have the regulator as thermostat. OK fine if you say so. ---- go ahead and use your cnstant, regulator. Electricity is charge does create heat, heat is what damages the system including the battery and alternator. Using a regulator controls this electricla flow.
http://www.autoshop101.com/trainmodules/alternator/alt131.html
The regulator will attempt to maintain a pre-determined charging system voltage level.

When charging system voltage falls below this point, the regulator will increase the field current, thus strengthening the magnetic field, which results in an increase of alternator output.

When charging system voltage raises above this point, the regulator will decrease field current , thus weakening the magnetic field, and results in a decrease of alternator output.
Also - http://www.familycar.com/Classroom/charging.htm
The voltage regulator can be mounted inside or outside of the alternator housing. If the regulator is mounted outside (common on some Ford products) there will be a wiring harness connecting it to the alternator.

The voltage regulator controls the field current applied to the spinning rotor inside the alternator. When there is no current applied to the field, there is no voltage produced from the alternator. When voltage drops below 13.5 volts, the regulator will apply current to the field and the alternator will start charging. When the voltage exceeds 14.5 volts, the regulator will stop supplying voltage to the field and the alternator will stop charging. This is how voltage output from the alternator is regulated. Amperage or current is regulated by the state of charge of the battery. When the battery is weak, the electromotive force (voltage) is not strong enough to hold back the current from the alternator trying to recharge the battery. As the battery reaches a state of full charge, the electromotive force becomes strong enough to oppose the current flow from the alternator, the amperage output from the alternator will drop to close to zero, while the voltage will remain at 13.5 to 14.5. When more electrical power is used, the electromotive force will reduce and alternator amperage will increase. It is extremely important that when alternator efficiency is checked, both voltage and amperage outputs are checked. Each alternator has a rated amperage output depending on the electrical requirements of the vehicle. About the same as hooking up and forgetting a constant, non voltage controlled battery charger of past years. Wouldn't think of doing that - would you?

Posted By: Supercuda

Re: voltage regulator for electronic ignition - 04/24/10 03:12 PM

Quote:

So now we have the regulator as thermostat. OK fine if you say so. ---- go ahead and use your cnstant, regulator.

I don't say so, MoPar says so. Period, end of discussion.

Why don't you research battery charging vs. ambient temps and you will UNDERSTAND why temperature compensation is important in a STOCK setup and irrelevant in a race one.

It is also the only difference between the stock regulator and the MP constant voltage one.

Posted By: RapidRobert

Re: voltage regulator for electronic ignition - 04/24/10 03:21 PM

Quote:

Why don't you research battery charging vs. ambient temps and you will UNDERSTAND why temperature compensation is important in a STOCK setup and irrelevant in a race one.
It is also the only difference between the stock regulator and the MP constant voltage one.

you know up until this time where you two guys has this "discussion" I never understood what the constant voltage concept meant

but now I'm grasping it. Thanks guys

(I'm serious).

Posted By: Dougsmopars

Re: voltage regulator for electronic ignition - 04/24/10 06:08 PM

There's a very hundred Mopars around here all useing the constant output regulator. Nobody has any complaints. Mine runs better with it more voltage to coil. I use a .8 ohm resistor. My local speed shop has been putting the constant out regulators in every electronic conversion since they came out. I've used them for years. Never had a problem. Never killed a battery. I'll stick with what i know works from my experience not what i read in the lastest issuse of hot rod mag.

Posted By: @#$%&*!

Re: voltage regulator for electronic ignition - 04/24/10 06:20 PM

Quote:

I have a 1969 Barracuda 340 engine with an electronic ignition and stock voltage regulator. The car is next to impossible to start when cold. The battery has 12.5 volts...

The voltage regulator doesn't do anything until the engine is running. If it's a cold start issue and the battery voltage is sufficient it's either a cranking circuit issue, an ignition output issue, or choke/fuel mixture problem.
Does it crank at normal speed when cold? If not, check/repair/replace cables, connections, battery, or starter.
If the cranking circuit checks out, try a jumper wire from the battery positive terminal to the coil + terminal when cranking. Remove the wire after the engine starts. If this fixes it you need better connections in the ignition circuit, a new ECU, or need to rig up a ballast resistor bypass.