using diodes to step up voltage

[BiggBoi]

Did it today using 2 6 amps got only a .6 increase hot.

98 Chevy Tahoe.

Stock 160 amp alt.

Gonna try 2 10 amps tomorrow to see if i get better results.

[Loudcivic]

Hey loudcivic, have you done this yet to your car? I'm curious if those diodes worked out for you

was gonna the other day but between the kids and wife i didnt get to lol. one of these days this week it will be done. if all goes well im making a little box and putting a knob on it and sealing it all up and mounting it under the hood with the diodes and pot inside. i will let you guys know as soon as i do it

[bdubii]

Cool, sounds like it should be a legit little set up for your voltage

[la negra]

pm sent to ami customs and 97ssblazer

[ImNotLoud]

at first i was charging at 15.2volts and now i am charging at 14.7 due to heat, should I add another diode till it starts to cool down again?

[Purplehaze]

at first i was charging at 15.2volts and now i am charging at 14.7 due to heat, should I add another diode till it starts to cool down again?

I wouldn't, 14.7 in warm weather is good.

[Purplehaze]

pm sent to ami customs and 97ssblazer

So, did you try it? If so, which one, brown or grey?

I'm guessing if you did, you're not liking the results?

[RockFord4lyfe]

okay so i was wondering if i could do this upgrade... was checking the tech data on my alt(stock 70 amp ) and it says:

"These types of Alternator do not have a traditional Regulators but instead have a field control Unit.

Mitsubishi & Hitachi Alternators with P-D Regulators require special testing, the voltage control &

warning lamp functions are in the vehicle PCM (Computer).

* P Terminal is Stator Phase & is a direct connection to stator AC Volts.

This allows the PCM to Monitor Alternator Field.

* D Terminal is Driver connected to Vehicle PCM (Computer), and is used to control the output of

the field control unit by varying base current on a transistor which in turn varies field current thereby

controlling Alternator output and voltage. These Alternators cannot be tested in the traditional manner

without dedicated testing equipment. Connecting battery voltage to the “D” terminal will destroy the unit."

The "P" and "D" terminals are the only 2 wires in the plug.. i figure if i put the diode(s) on the "D" wire it should work.. but i don't know... help?

[Guest DC Power Rob]

DO NOT TRY THIS ON YOUR CAR!! The PD setup is a hyrbrid system where the PCM has the field "controller" and the alternator has the field "switch".. In laymans terms, the "D" wire is the driver wire, it's a pwm signal from the PCM to the alternator telling the switch at what duty cycle to run at, the "P" wire is an output function back to the PCM to let the PCM know what load the alternator is running. You CAN NOT manipulate this system in any way, shape, or form. You CAN cause some very expensive, un-necessary repairs however, trust me, I've seen them first hand.. Unfortunately, you are stuck with whatever voltage the PCM want's you to be stuck with..

For all others who attempt to try this, yes, putting a diode or resistor on your sense line will raise voltage, but don't do it unless you ABSOLUTELY know what your doing.. On EVERY GM made from '86 up, the S wire is the sense wire if so equipped, some vehicles however dont run an external sensing regulator and only have the LF terminals (which is different than the 2 pin RVC altogether).. Don't ever start putting resistors/diodes on any L or F or P terminals.. On the L wire, you can overload the lamp driver and smoke the regulator, on the F wire, your going to raise/drop the field monitor voltage to the PCM and your vehicle will not like you, and unless you really want to start blowing diodes up, by all means don't put a diode on the P terminal unless you want to directly short your diodes out. P=phase, it's a hard wired pinout to the stator, and has a constant ~7.36v DC output..

On ALL Ford vehicles, 3,4,6G including PCM controlled alts, be forewarned... The A wire is the sense wire, and it's also the battery supply for the regulator, putting diodes inline on a power supply wasn't a good idea last time I checked.. This is why some manufacturers don't have a voltage "manipulation" device for Fords. Your not just "tricking" the sense terminal like you are on a GM alternator, you're messing with the input power supply to the voltage regulator and Ford regulators just, don't, like it.. (Why Ford thought not putting the power supply internal is beyond me, they are/were the ONLY manufacturer to ever do it) 90% of failures on Ford voltage regulators are because of this type problem on the A wire. Anyone familiar with ohms law? What happens when you drop input voltage to a device that always needs a constant wattage input? Current goes up, what does more current =, more heat. Might want to re-think this one guys... It will get you higher voltage, sometimes, but it's very, very unpredictable, and extremely un-reliable and not worth an extra .5-1v..

I'm all for people doing DIY projects, just do it with some knowledge.. I don't sell anything even remotely related to this so I have absolutely nothing to gain/lose by sharing this info. I just don't want to see people doing things wrong...

okay so i was wondering if i could do this upgrade... was checking the tech data on my alt(stock 70 amp ) and it says:

"These types of Alternator do not have a traditional Regulators but instead have a field control Unit.

Mitsubishi & Hitachi Alternators with P-D Regulators require special testing, the voltage control &

warning lamp functions are in the vehicle PCM (Computer).

* P Terminal is Stator Phase & is a direct connection to stator AC Volts.

This allows the PCM to Monitor Alternator Field.

* D Terminal is Driver connected to Vehicle PCM (Computer), and is used to control the output of

the field control unit by varying base current on a transistor which in turn varies field current thereby

controlling Alternator output and voltage. These Alternators cannot be tested in the traditional manner

without dedicated testing equipment. Connecting battery voltage to the "D" terminal will destroy the unit."

The "P" and "D" terminals are the only 2 wires in the plug.. i figure if i put the diode(s) on the "D" wire it should work.. but i don't know... help?

[Guest DC Power Rob]

Just FYI, this is only true on some Honda's/Acuras. If I remember correctly, the last vehicles to use an S type regulator were Integra GSR's and Legends. The green/white wire is normally the C wire on Honda's, NOT the S wire. The C wire is what the PCM sends a ground signal to the alternator to shut it off in economy mode. Gound the C terminal on a Honda, alt goes off like a lightswitch just like it's supposed to. You want better voltage on Honda's, just CUT the C wire and just stop the PCM from shutting the alt off.. If you try to put an inline diode on a C wire to B+ on ANY Honda, you WILL blow the regulator up. Just FYI, to my knowledge, from ~2002 there wasn't a single mainstream Honda/Acura made that had a sensing type regulator, and the last one I can think of was the Acura legend in '01-'02. No Civic or Accord has used an S type regulator since the early '90s, the last Civic to use it was I think '89...

IF YOU DONT HAVE ANY IDEA OR ANY MECHANICAL SENSE WITH WORKING ON VEHICLES PLEASE DO NOT TRY THIS. TRY AT YOUR OWN RISK NONE OF US ARE HELD RESPONSIBLE FOR YOUR ACTIONS

spl kid: yes im gonna do it lol i just gotta wait for some damn weather to work in. we had a bad snow storm then its been raining a lot so i havent been able to tear into it yet. im gonna go pick up my diodes and i have a few pots from volt modding videocards lol

also ill link you all to some of the reading i was doing before this thread was posted

good read here and at the bottom he made his own http://www.amsterdam...e_regulator.htm

edit: FOR HONDA'S AND ACURA'S ONLY

White/Blue Wire = 'L' wire. I assume this means LIGHT, because it is the warning light in the other diagrams. Seems to connect to the Black/Yellow, my guess is it checks the voltage on that wire, and if it is too high/low it will trip the 'warning light'

White/Green = "S" wire. Goes to underhood relay box, FUSE 8 (10A), according to the manual, fuse 8 is the voltage regulator.

Black/Yellow = "IG" wire. goes to ignition switch, coil, condenser etc,

White/Red = "FR" wire. Goes to ECU, dunno what it does there other than the previously mentioned confusing ACGF.

the "S" aka sense wire is the wire that needs the diodes added in to trick it.

sense wires OBD2 = WHITE/GREEN OBD1 = WHITE/YELLOW

it can be done on either hondas or acuras with the color wire shown.

heres another one for you honda/acura guys

"S" is the sense line. This helps the voltage regulator inside the alt. maintain the proper voltage. The idea is to sense the actual voltage from a more remote part of the power system. This could be connected to any positive voltage source really. The battery + terminal or the main lug on the starter would be a good choice.

so we add the diodes to that sense wire it will trick it and it will raise the voltage for us.

i will be doing testing with my car maybe tomorrow if the weather permits

edit 2: also if you are capable of doing this mod all you have to do is look up your alternator wiring spec sheet and find out which one is the sense wire